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• How to install 32-bit libraries using Debian Testing

  - by bgoodr

  Question: What is the way to determine, ahead of time and without doing a full install of 64-bit Debian Testing NETINST, when Debian Testing has 32-bit libraries available and fully working and installable so that the following command works without broken package errors?: apt-get install ia32-libs ia32-libs-gtk The errors that occur when 32-bit libraries are not available, still in some broken state, or whatever is broken are detailed below. I already have concluded that "Just install Stable" is my stop-gap measure for now, but I would like to know the answer to the above question so as to avoid a lengthy installation process only to run into these problems at the very end. Details: I downloaded the 64-bit Debian Testing netinst a couple of days ago. This was "Jessie" built 20131014-06:07 via http://tinyurl.com/lejpa. This is weekly testing build. Yes, I know I should expect problems, and I did. I managed to get it completely installed and was able to invoke into GNOME, but not get past the 32-bit library problem. The problems starts when I attempt to install the 32-bit libraries via: apt-get install ia32-libs ia32-libs-gtk that returns: root@breath:~# apt-get install ia32-libs ia32-libs-gtk Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: ia32-libs : Depends: ia32-libs-i386 but it is not installable ia32-libs-gtk : Depends: ia32-libs-i386 but it is not installable Depends: ia32-libs-gtk-i386 but it is not installable E: Unable to correct problems, you have held broken packages. I then found an old (2012 is old to me) answer at ia32-libs : Depends: ia32-libs-i386 but it is not installable and even tried what they suggested there which was dpkg --add-architecture i386 apt-get update After executing the above, I tried again but got: root@breath:~# apt-get install ia32-libs ia32-libs-gtk Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: ia32-libs : Depends: ia32-libs-i386 ia32-libs-gtk : Depends: ia32-libs-i386 E: Unable to correct problems, you have held broken packages. root@breath:~# And then tried this: root@breath:~# dpkg --get-selections | grep hold And that returned nothing. Not only is there broken packages, the system doesn't even know what packages are broken, so Debian Stable is my only solution I know of right now. Hence my question above.

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• Slow Memcached: Average 10ms memcached `get`

  - by Chris W.

  We're using Newrelic to measure our Python/Django application performance. Newrelic is reporting that across our system "Memcached" is taking an average of 12ms to respond to commands. Drilling down into the top dozen or so web views (by # of requests) I can see that some Memcache get take up to 30ms; I can't find a single use of Memcache get that returns in less than 10ms. More details on the system architecture: Currently we have four application servers each of which has a memcached member. All four memcached members participate in a memcache cluster. We're running on a cloud hosting provider and all traffic is running across the "internal" network (via "internal" IPs) When I ping from one application server to another the responses are in ~0.5ms Isn't 10ms a slow response time for Memcached? As far as I understand if you think "Memcache is too slow" then "you're doing it wrong". So am I doing it wrong? Here's the output of the memcache-top command: memcache-top v0.7 (default port: 11211, color: on, refresh: 3 seconds) INSTANCE USAGE HIT % CONN TIME EVICT/s GETS/s SETS/s READ/s WRITE/s cache1:11211 37.1% 62.7% 10 5.3ms 0.0 73 9 3958 84.6K cache2:11211 42.4% 60.8% 11 4.4ms 0.0 46 12 3848 62.2K cache3:11211 37.5% 66.5% 12 4.2ms 0.0 75 17 6056 170.4K AVERAGE: 39.0% 63.3% 11 4.6ms 0.0 64 13 4620 105.7K TOTAL: 0.1GB/ 0.4GB 33 13.9ms 0.0 193 38 13.5K 317.2K (ctrl-c to quit.) ** Here is the output of the top command on one machine: ** (Roughly the same on all cluster machines. As you can see there is very low CPU utilization, because these machines only run memcache.) top - 21:48:56 up 1 day, 4:56, 1 user, load average: 0.01, 0.06, 0.05 Tasks: 70 total, 1 running, 69 sleeping, 0 stopped, 0 zombie Cpu(s): 0.0%us, 0.0%sy, 0.0%ni, 99.7%id, 0.0%wa, 0.0%hi, 0.0%si, 0.3%st Mem: 501392k total, 424940k used, 76452k free, 66416k buffers Swap: 499996k total, 13064k used, 486932k free, 181168k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 6519 nobody 20 0 384m 74m 880 S 1.0 15.3 18:22.97 memcached 3 root 20 0 0 0 0 S 0.3 0.0 0:38.03 ksoftirqd/0 1 root 20 0 24332 1552 776 S 0.0 0.3 0:00.56 init 2 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kthreadd 4 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kworker/0:0 5 root 20 0 0 0 0 S 0.0 0.0 0:00.02 kworker/u:0 6 root RT 0 0 0 0 S 0.0 0.0 0:00.00 migration/0 7 root RT 0 0 0 0 S 0.0 0.0 0:00.62 watchdog/0 8 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 cpuset 9 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 khelper ...output truncated...

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• Understanding packet flows over RVI

  - by choco-loo

  I'm trying to get a full grasp of firewall filters and how to apply them on a Juniper EX4200 switch - to be able to block ports, police traffic and shape traffic. The network architecture is as follows internet >-< vlan4000 >-< vlan43 vlan4000 is a public "routed" block (where all the IPs are routed to and the internet gw is) vlan43 is a vlan with public IPs with devices (servers) attached There are static routes and RVI's on the EX4200 to send all traffic via vlan4000's gateway to reach the internet. I've set up filters on both input and output of the respective RVI's and VLAN's - with simple counters, to measure traffic flow from a server inside of vlan43 and a server on the internet. Using a combination of iperf for UDP and TCP tests and fping for ICMP tests - I observed the following, icmp vlan43>internet internet>vlan43 unit4000-counter-in 0 0 unit4000-counter-out 0 0 unit43-counter-in 100 100 unit43-counter-out 0 0 vlan4000-counter-in 6 4 vlan4000-counter-out 107 104 vlan43-counter-in 101 100 vlan43-counter-out 100 100 tcp vlan43>internet internet>vlan43 unit4000-counter-in 0 0 unit4000-counter-out 0 0 unit43-counter-in 73535 38480 unit43-counter-out 0 0 vlan4000-counter-in 7 8 vlan4000-counter-out 73543 38489 vlan43-counter-in 73535 38481 vlan43-counter-out 38938 75880 udp vlan43>internet internet>vlan43 unit4000-counter-in 0 0 unit4000-counter-out 0 0 unit43-counter-in 81410 1 unit43-counter-out 0 0 vlan4000-counter-in 18 7 vlan4000-counter-out 81429 8 vlan43-counter-in 81411 1 vlan43-counter-out 1 85472 My key goals are to set up a few filters and policers, as there will be many more VLANs - that all need protecting from each other and the internet. Then globally limit/police all outbound traffic to the internet Block inbound ports to vlan43 (eg. 22) Limit outbound traffic from vlan43 (to the internet) Limit outbound traffic from vlan43 (to other vlans) Limit outbound traffic from vlan4000 (to the internet from all vlans) Route traffic from vlans via specific routing instances (FBF) The question What I want to understand is why there isn't ever any activity on unit4000 or vlan4000 inbound or outbound counter - is this because there isn't a device on this VLAN - and that the traffic is only traversing it? And with regards to the TCP test - why is there twice as many packets on unit43-counter-in, vlan4000-counter-out and vlan43-counter-in - is this counting both the inbound and outbound traffic?

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• Linux per-process resource limits - a deep Red Hat Mystery

  - by BobBanana

  I have my own multithreaded C program which scales in speed smoothly with the number of CPU cores.. I can run it with 1, 2, 3, etc threads and get linear speedup.. up to about 5.5x speed on a 6-core CPU on a Ubuntu Linux box. I had an opportunity to run the program on a very high end Sunfire x4450 with 4 quad-core Xeon processors, running Red Hat Enterprise Linux. I was eagerly anticipating seeing how fast the 16 cores could run my program with 16 threads.. But it runs at the same speed as just TWO threads! Much hair-pulling and debugging later, I see that my program really is creating all the threads, they really are running simultaneously, but the threads themselves are slower than they should be. 2 threads runs about 1.7x faster than 1, but 3, 4, 8, 10, 16 threads all run at just net 1.9x! I can see all the threads are running (not stalled or sleeping), they're just slow. To check that the HARDWARE wasn't at fault, I ran SIXTEEN copies of my program independently, simultaneously. They all ran at full speed. There really are 16 cores and they really do run at full speed and there really is enough RAM (in fact this machine has 64GB, and I only use 1GB per process). So, my question is if there's some OPERATING SYSTEM explanation, perhaps some per-process resource limit which automatically scales back thread scheduling to keep one process from hogging the machine. Clues are: My program does not access the disk or network. It's CPU limited. Its speed scales linearly on a single CPU box in Ubuntu Linux with a hexacore i7 for 1-6 threads. 6 threads is effectively 6x speedup. My program never runs faster than 2x speedup on this 16 core Sunfire Xeon box, for any number of threads from 2-16. Running 16 copies of my program single threaded runs perfectly, all 16 running at once at full speed. top shows 1600% of CPUs allocated. /proc/cpuinfo shows all 16 cores running at full 2.9GHz speed (not low frequency idle speed of 1.6GHz) There's 48GB of RAM free, it is not swapping. What's happening? Is there some process CPU limit policy? How could I measure it if so? What else could explain this behavior? Thanks for your ideas to solve this, the Great Xeon Slowdown Mystery of 2010!

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• Possible capacitor plague - need help identifying

  - by cornjuliox

  I've been having some PC power issues lately, and I think I've tracked it down to a bad power supply. Lately, when I'm on my PC it will often restart without warning, displaying "Hypertransport sync flood error occurred last boot." once POST finishes. I've googled the error, but can't come to a definitive conclusion as to what's causing it. I've seen posts suggesting that it might be a power supply issue, but nothing conclusive. Here's what I've done so far: -I haven't installed anything suspect within the last 3 months. -I do overclock just a tiny bit, so I tried raising the voltages a little. That didn't work so I brought both CPU multiplier and voltages all back to their default settings, but that didn't solve the problem either. The problem still occurs. -AV scanned the whole system, nothing suspect. -I suspected that it might be a bad power supply so I cracked that open and found the following: I think it might be cap plague, but I'm not sure. It looks more like glue TBH. Could someone help me figure out what might be wrong with this PC? EDIT: Sometimes, after these restarts, I noticed that the GPU fan doesn't spin up, and the single rear case fan that just happens to be connected to the same molex Y-cable as the GFX card doesn't spin up either. Anything to that? EDIT 2: I do use the system quite heavily, but I don't know how that will factor into this. I often play Diablo 3 and EVE Online at the same time, frequently alt-tabbing between the two. I also have Firefox open in the background, sometimes with several tabs, and if I feel like it, I'll mute the in-game sound and open foobar2000 for better music. Could it be that I'm just pushing this thing too hard? EDIT 3: I also noticed something odd. Right before I experience these restarts, my monitor would suffer from very faint lines of static moving across the screen. The monitor is still very much useable, but it is very annoying. Following the restart it disappears, and then would gradually re-appear over the next few days, and then restarts again. I find it to be very odd. System specs for good measure: Orion 600 W PSU AMD Athlon II X3 440 (overclocked to 3.14 ghZ, raised the CPU multiplier to x13 from x10) MSI G40-775 motherboard 1 GB inno3D GTX 550 ti 4 GB DDR3 RAM 500 GB Samsung SATA HD

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• How can I change exim's DKIM and SPF for emails sent?

  - by 0pt1m1z3

  I've now spent 2 hours trying to figure out this issue and I am about to give up and go to bed. I've been having issues with Gmail rejecting emails from my VPS server because of false spam alerts (probably caused by lfd sending too many emails). So I changed my Exim config to send emails from a different IP (my VPS comes with 3) and that fixed the issue. I also enabled DKIM and SPF on my domains for added measure. But now, all my emails appear as ("From: Sender Name via server.domain1.com") where server.domain1.com is my VPS hostname. I previously had the same issue in Outlook and turning off "Set SMTP Sender: headers" solved that problem. But I believe adding the DKIM and SPF now makes Gmail add "via server.domain1.com" to my messages. How do I fix this? This is a typical header for a message (as it appears at gmail): Delivered-To: [email protected] Received: by 10.60.44.163 with SMTP id f3csp248622oem; Thu, 29 Mar 2012 21:23:18 -0700 (PDT) Received: by 10.50.106.200 with SMTP id gw8mr452788igb.10.1333081398523; Thu, 29 Mar 2012 21:23:18 -0700 (PDT) Return-Path: <[email protected]> Received: from domain2.com ([X.X.X.X]) by mx.google.com with ESMTPS id y1si810998igb.3.2012.03.29.21.23.18 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 29 Mar 2012 21:23:18 -0700 (PDT) Received-SPF: pass (google.com: domain of [email protected] designates X.X.X.X as permitted sender) client-ip=X.X.X.X; Authentication-Results: mx.google.com; spf=pass (google.com: domain of [email protected] designates X.X.X.X as permitted sender) [email protected]; dkim=pass [email protected] DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=server.domain1.com; s=default; h=Date:Message-Id:From:Content-type:MIME-Version:Subject:To; bh=wF8bBRgh01EYg4t5DAeVPv1Ps906UVIeRnQCb/HvSYw=; b=k/Pg7lnrO+Ud/z1mOTv+O/3DiJzzQgyBhfIizIaFHM8tF/eNJt5P2k+9yQB224sxYstZIWwVRBJmiqvcM1QhARv1HWqWma0crppZ3JOn+LRHANan634OBi+58SIRA+gu; Received: (Exim 4.77) id 1SDTVE-0005HA-9Y for [email protected]; Fri, 30 Mar 2012 00:31:56 -0400 To: [email protected] Subject: Password Reset Request MIME-Version: 1.0 Content-type: text/html; charset=iso-8859-1 From: Sender Name <[email protected]> Message-Id: <[email protected]> Date: Fri, 30 Mar 2012 00:31:56 -0400 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - server.domain1.com X-AntiAbuse: Original Domain - domain2.com X-AntiAbuse: Originator/Caller UID/GID - [507 504] / [47 12] X-AntiAbuse: Sender Address Domain - server.domain1.com

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• Confused with DKIM, SPF and Exim Configs

  - by 0pt1m1z3

  I've now spent 2 hours trying to figure out this issue and I am about to give up and go to bed. I've been having issues with Gmail rejecting emails from my VPS server because of false spam alerts (probably caused by lfd sending too many emails). So I changed my Exim config to send emails from a different IP (my VPS comes with 3) and that fixed the issue. I also enabled DKIM and SPF on my domains for added measure. But now, all my emails appear as ("From: Sender Name via server.domain1.com") where server.domain1.com is my VPS hostname. I previously had the same issue in Outlook and turning off "Set SMTP Sender: headers" solved that problem. But I believe adding the DKIM and SPF now makes Gmail add "via server.domain1.com" to my messages. How do I fix this? This is a typical header for a message (as it appears at gmail): Delivered-To: [email protected] Received: by 10.60.44.163 with SMTP id f3csp248622oem; Thu, 29 Mar 2012 21:23:18 -0700 (PDT) Received: by 10.50.106.200 with SMTP id gw8mr452788igb.10.1333081398523; Thu, 29 Mar 2012 21:23:18 -0700 (PDT) Return-Path: <[email protected]> Received: from domain2.com ([X.X.X.X]) by mx.google.com with ESMTPS id y1si810998igb.3.2012.03.29.21.23.18 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 29 Mar 2012 21:23:18 -0700 (PDT) Received-SPF: pass (google.com: domain of [email protected] designates X.X.X.X as permitted sender) client-ip=X.X.X.X; Authentication-Results: mx.google.com; spf=pass (google.com: domain of [email protected] designates X.X.X.X as permitted sender) [email protected]; dkim=pass [email protected] DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=server.domain1.com; s=default; h=Date:Message-Id:From:Content-type:MIME-Version:Subject:To; bh=wF8bBRgh01EYg4t5DAeVPv1Ps906UVIeRnQCb/HvSYw=; b=k/Pg7lnrO+Ud/z1mOTv+O/3DiJzzQgyBhfIizIaFHM8tF/eNJt5P2k+9yQB224sxYstZIWwVRBJmiqvcM1QhARv1HWqWma0crppZ3JOn+LRHANan634OBi+58SIRA+gu; Received: (Exim 4.77) id 1SDTVE-0005HA-9Y for [email protected]; Fri, 30 Mar 2012 00:31:56 -0400 To: [email protected] Subject: Password Reset Request MIME-Version: 1.0 Content-type: text/html; charset=iso-8859-1 From: Sender Name <[email protected]> Message-Id: <[email protected]> Date: Fri, 30 Mar 2012 00:31:56 -0400 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - server.domain1.com X-AntiAbuse: Original Domain - domain2.com X-AntiAbuse: Originator/Caller UID/GID - [507 504] / [47 12] X-AntiAbuse: Sender Address Domain - server.domain1.com

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• APC PHP cache size does not exceed 32MB, even though settings allow for more

  - by hardy101

  I am setting up APC (v 3.1.9) on a high-traffic WordPress installation on CentOS 6.0 64 bit. I have figured out many of the quirks with APC, but something is still not quite right. No matter what settings I change, APC never actually caches more than 32MB. I'm trying to bump it up to 256 MB. 32MB is a default amount for apc.shm_size, so I am wondering if it's stuck there somehow. I have run the following echo '2147483648' > /proc/sys/kernel/shmmax to increase my system's shared memory to 2G (half of my 4G box). Then ran ipcs -lm which returns ------ Shared Memory Limits -------- max number of segments = 4096 max seg size (kbytes) = 2097152 max total shared memory (kbytes) = 8388608 min seg size (bytes) = 1 Also made a change in /etc/sysctl.conf then ran sysctl -p to make the settings stick on the server. Rebooted, too, for good measure. In my APC settings, I have mmap enabled (which happens by default in recent versions of APC). php.ini looks like: apc.stat=0 apc.shm_size="256M" apc.max_file_size="10M" apc.mmap_file_mask="/tmp/apc.XXXXXX" apc.ttl="7200" I am aware that mmap mode will ignore references to apc.shm_segments, so I have left it out with default 1. phpinfo() indicates the following about APC: Version 3.1.9 APC Debugging Disabled MMAP Support Enabled MMAP File Mask /tmp/apc.bPS7rB Locking type pthread mutex Locks Serialization Support php Revision $Revision: 308812 $ Build Date Oct 11 2011 22:55:02 Directive Local Value apc.cache_by_default On apc.canonicalize O apc.coredump_unmap Off apc.enable_cli Off apc.enabled On On apc.file_md5 Off apc.file_update_protection 2 apc.filters no value apc.gc_ttl 3600 apc.include_once_override Off apc.lazy_classes Off apc.lazy_functions Off apc.max_file_size 10M apc.mmap_file_mask /tmp/apc.bPS7rB apc.num_files_hint 1000 apc.preload_path no value apc.report_autofilter Off apc.rfc1867 Off apc.rfc1867_freq 0 apc.rfc1867_name APC_UPLOAD_PROGRESS apc.rfc1867_prefix upload_ apc.rfc1867_ttl 3600 apc.serializer default apc.shm_segments 1 apc.shm_size 256M apc.slam_defense On apc.stat Off apc.stat_ctime Off apc.ttl 7200 apc.use_request_time On apc.user_entries_hint 4096 apc.user_ttl 0 apc.write_lock On apc.php reveals the following graph, no matter how long the server runs (cache size fluctuates and hovers at just under 32MB. See image http://i.stack.imgur.com/2bwMa.png You can see that the cache is trying to allocate 256MB, but the brown piece of the pie keeps getting recycled at 32MB. This is confirmed as refreshing the apc.php page shows cached file counts that move up and down (implying that the cache is not holding onto all of its files). Does anyone have an idea of how to get APC to use more than 32 MB for its cache size?? **Note that the identical behavior occurs for eaccelerator, xcache, and APC. I read here: http://www.litespeedtech.com/support/forum/archive/index.php/t-5072.html that suEXEC could cause this problem.

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• Windows server detected error with hard disk

  - by user53864

  We have hosting Windows server 2008 R2 and I am working as admin in small company. The server is hanging and restarting as the hard disk seems to be damaged due to power fluctutaion(though having inverter) as it's showing the below error message on server reboot: Problem detected with the hard disk Press any key to continue It's Seagate 1TB SATA hard disk and it's booting after pressing enter. So it's clear that the hard disk is dying. Yes, it's in warranty but it's fact that warranty won't recover the lincesed windows server 2008 and it's data. As it's booting now, I backed up required things and I am thinking to clone the entire hard disk. The first thing it striked me is checking on the Seagate site if any tool available for cloning and I found Seagate DiskWizard but not specified it for windows server 2008. Please anybody could help me giving your best ideas for the below: Urgently, What's the best way(free of cost) for me to clone in my case with the new same sized hard disk? It's a one time lincenced and I cannot use the same key again if I reinstall the server. Will the lincense be carried with new disk if cloned? else there is a way to contact Microsoft explaining the problem occurred, to obtain new key for no charge?. I want to take measure for future. How do I keep two disks in continuous sync? mirrored & raid are the only options converting the disks to dynamic? or is there a best way I could do with no additional charge?. Any help is greatly appreciated. Thank you! EDIT:1 I started cloning the disk with CloneZilla and it was going proper showing in GUI. But after some time there is no GUI but a black screen with some codes(looks like disk location numbers) going page by page(I have attached the screenshots below captured from my phone). Do you people think it's actually cloning?. I started in the morning and it's evening now. I left the office now to let it finish what it's trying to do and I'll go & check it tomorrow. Slowly lost hope, don't know what face it's going to show tomorrow. Any ideas?

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• [CentOS 4.8] nslookup resolves domains to IPs, but I can't get a response to pings to external servers

  - by Beco

  I have a fresh install of CentOS 4.8 running on an internal development server. I haven't done anything to it besides setting up sudoers and SSH. I can SSH into the server and from there resolve domains to IPs and ping internal servers, but for some reason I don't get any response from pinging external servers. The software firewall is disabled, and the problem is present with both static and DHCP-assigned network configurations. The network domain controller is a Windows Server 2003 box. $ nslookup google.com Server: 10.254.2.5 Address: 10.254.2.5#53 Non-authoritative answer: Name: google.com Address: 74.125.47.147 Name: google.com Address: 74.125.47.99 <etc...> 10.254.2.5 is the Win2K3 server. $ ping google.com PING google.com (74.125.47.106) 56(84) bytes of data. It just hangs here indefinitely. $ cat /etc/resolv.conf ; generated by /sbin/dhclient-script search <...snip...>.local nameserver 10.254.2.5 nameserver 10.254.2.124 10.254.2.124 is the backup DC server, which is currently off and tombstoned by this point. The snipped section is our company name. # ifconfig eth0 Link encap:Ethernet HWaddr <snip> inet addr:10.254.2.101 Bcast:10.254.2.255 Mask:255.255.255.0 inet6 addr: <snip>/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:80066 errors:0 dropped:0 overruns:0 frame:0 TX packets:4421 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:7810133 (7.4 MiB) TX bytes:590550 (576.7 KiB) Interrupt:225 Base address:0xc000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:32 errors:0 dropped:0 overruns:0 frame:0 TX packets:32 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:8104 (7.9 KiB) TX bytes:8104 (7.9 KiB) # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.254.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0 0.0.0.0 10.254.2.5 0.0.0.0 UG 0 0 0 eth0 And, for good measure, a snapshot of the current ethernet config via the system-config-network GUI. Edit: I don't yet have enough rep to post images, so here's a link. Sorry! system-config-network snapshot I'm pretty green when it comes to setting up *nix dev servers and network configuration in general, so please let me know if I've left out critical information, or posted information I shouldn't have posted. Thanks!

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• Form, function and complexity in rule processing

  - by Charles Young

  Tim Bass posted on ‘Orwellian Event Processing’. I was involved in a heated exchange in the comments, and he has more recently published a post entitled ‘Disadvantages of Rule-Based Systems (Part 1)’. Whatever the rights and wrongs of our exchange, it clearly failed to generate any agreement or understanding of our different positions. I don't particularly want to promote further argument of that kind, but I do want to take the opportunity of offering a different perspective on rule-processing and an explanation of my comments. For me, the ‘red rag’ lay in Tim’s claim that “...rules alone are highly inefficient for most classes of (not simple) problems” and a later paragraph that appears to equate the simplicity of form (‘IF-THEN-ELSE’) with simplicity of function.   It is not the first time Tim has expressed these views and not the first time I have responded to his assertions.   Indeed, Tim has a long history of commenting on the subject of complex event processing (CEP) and, less often, rule processing in ‘robust’ terms, often asserting that very many other people’s opinions on this subject are mistaken.   In turn, I am of the opinion that, certainly in terms of rule processing, which is an area in which I have a specific interest and knowledge, he is often mistaken. There is no simple answer to the fundamental question ‘what is a rule?’ We use the word in a very fluid fashion in English. Likewise, the term ‘rule processing’, as used widely in IT, is equally difficult to define simplistically. The best way to envisage the term is as a ‘centre of gravity’ within a wider domain. That domain contains many other ‘centres of gravity’, including CEP, statistical analytics, neural networks, natural language processing and so much more. Whole communities tend to gravitate towards and build themselves around some of these centres. The term 'rule processing' is associated with many different technology types, various software products, different architectural patterns, the functional capability of many applications and services, etc. There is considerable variation amongst these different technologies, techniques and products. Very broadly, a common theme is their ability to manage certain types of processing and problem solving through declarative, or semi-declarative, statements of propositional logic bound to action-based consequences. It is generally important to be able to decouple these statements from other parts of an overall system or architecture so that they can be managed and deployed independently.  As a centre of gravity, ‘rule processing’ is no island. It exists in the context of a domain of discourse that is, itself, highly interconnected and continuous.   Rule processing does not, for example, exist in splendid isolation to natural language processing.   On the contrary, an on-going theme of rule processing is to find better ways to express rules in natural language and map these to executable forms.   Rule processing does not exist in splendid isolation to CEP.   On the contrary, an event processing agent can reasonably be considered as a rule engine (a theme in ‘Power of Events’ by David Luckham).   Rule processing does not live in splendid isolation to statistical approaches such as Bayesian analytics. On the contrary, rule processing and statistical analytics are highly synergistic.   Rule processing does not even live in splendid isolation to neural networks. For example, significant research has centred on finding ways to translate trained nets into explicit rule sets in order to support forms of validation and facilitate insight into the knowledge stored in those nets. What about simplicity of form?   Many rule processing technologies do indeed use a very simple form (‘If...Then’, ‘When...Do’, etc.)   However, it is a fundamental mistake to equate simplicity of form with simplicity of function.   It is absolutely mistaken to suggest that simplicity of form is a barrier to the efficient handling of complexity.   There are countless real-world examples which serve to disprove that notion.   Indeed, simplicity of form is often the key to handling complexity. Does rule processing offer a ‘one size fits all’. No, of course not.   No serious commentator suggests it does.   Does the design and management of large knowledge bases, expressed as rules, become difficult?   Yes, it can do, but that is true of any large knowledge base, regardless of the form in which knowledge is expressed.   The measure of complexity is not a function of rule set size or rule form.  It tends to be correlated more strongly with the size of the ‘problem space’ (‘search space’) which is something quite different.   Analysis of the problem space and the algorithms we use to search through that space are, of course, the very things we use to derive objective measures of the complexity of a given problem. This is basic computer science and common practice. Sailing a Dreadnaught through the sea of information technology and lobbing shells at some of the islands we encounter along the way does no one any good.   Building bridges and causeways between islands so that the inhabitants can collaborate in open discourse offers hope of real progress.

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• Oracle OpenWorld Preview: Real World Perspectives from Oracle WebCenter Customers

  - by Christie Flanagan

  Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} If you frequent the Oracle WebCenter blog you’ve probably read a lot about the customer experience revolution over the last few months.  An important aspect of the customer experience revolution is the increasing role that peers play in influencing how others perceive a product, brand or solution, simply by sharing their own, real-world experiences.  Think about it, who do you trust more -- marketers and sales people pitching polished messages or peers with similar roles and similar challenges to the ones you face in your business every day? With this spirit in mind, this polished marketer personally invites you to hear directly from Oracle WebCenter customers about their real-life experiences during our customer panel sessions at Oracle OpenWorld next week.  If you’re currently using WebCenter, thinking about it, or just want to find out more about best practices in social business, next-generation portals, enterprise content management or web experience management, be sure to attend these sessions: CON8899 - Becoming a Social Business: Stories from the Front Lines of Change Wednesday, Oct 3, 11:45 AM - 12:45 PM - Moscone West - 3000Priscilla Hancock - Vice President/CIO, University of Louisville Kellie Christensen - Director of Information Technology, Banner EngineeringWhat does it really mean to be a social business? How can you change your organization to embrace social approaches? What pitfalls do you need to avoid? In this lively panel discussion, customer and industry thought leaders in social business explore these topics and more as they share their stories of the good, the bad, and the ugly that can happen when embracing social methods and technologies to improve business success. Using moderated questions and open Q&A from the audience, the panel discusses vital topics such as the critical factors for success, the major issues to avoid, how to gain senior executive support for social efforts, how to handle undesired behavior, and how to measure business impact. This session will take a thought-provoking look at becoming a social business from the inside. CON8900 - Building Next-Generation Portals: An Interactive Customer Panel DiscussionWednesday, Oct 3, 5:00 PM - 6:00 PM - Moscone West - 3000Roberts Wayne - Director, IT, Canadian Partnership Against CancerMike Beattie - VP Application Development, Aramark Uniform ServicesJohn Chen - Utilities Services Manager 6, Los Angeles Department of Water & PowerJörg Modlmayr - Head of Product Managment, Siemens AGSocial and collaborative technologies have changed how people interact, learn, and collaborate, and providing a modern, social Web presence is imperative to remain competitive in today’s market. Can your business benefit from a more collaborative and interactive portal environment for employees, customers, and partners? Attend this session to hear from Oracle WebCenter Portal customers as they share their strategies and best practices for providing users with a modern experience that adapts to their needs and includes personalized access to content in context. The panel also addresses how customers have benefited from creating next-generation portals by migrating from older portal technologies to Oracle WebCenter Portal. CON8898 - Land Mines, Potholes, and Dirt Roads: Navigating the Way to ECM NirvanaThursday, Oct 4, 12:45 PM - 1:45 PM - Moscone West - 3001Stephen Madsen - Senior Management Consultant, Alberta Agriculture and Rural DevelopmentHimanshu Parikh - Sr. Director, Enterprise Architecture & Middleware, Ross Stores, Inc.Ten years ago, people were predicting that by this time in history, we’d be some kind of utopian paperless society. As we all know, we're not there yet, but are we getting closer? What is keeping companies from driving down the road to enterprise content management bliss? Most people understand that using ECM as a central platform enables organizations to expedite document-centric processes, but most business processes in organizations are still heavily paper-based. Many of these processes could be automated and improved with an ECM platform infrastructure. In this panel discussion, you’ll hear from Oracle WebCenter customers that have already solved some of these challenges as they share their strategies for success and roads to avoid along your journey. CON8897 - Using Web Experience Management to Drive Online Marketing SuccessThursday, Oct 4, 2:15 PM - 3:15 PM - Moscone West - 3001Blane Nelson - Chief Architect, Ancestry.comMike Remedios - CIO, ArbonneCaitlin Scanlon - Product Manager, Monster WorldwideEvery year, the online channel becomes more imperative for driving organizational top-line revenue, but for many companies, mastering how to best market their products and services in a fast-evolving online world with high customer expectations for personalized experiences can be a complex proposition. Come to this panel discussion, and hear directly from customers on how they are succeeding today by using Web experience management to drive marketing success, using capabilities such as targeting and optimization, user-generated content, mobile site publishing, and site visitor personalization to deliver engaging online experiences. Your Handy Guide to WebCenter at Oracle OpenWorld Want a quick and easy guide to all the keynotes, demos, hands-on labs and WebCenter sessions you definitely don't want to miss at Oracle OpenWorld? Download this handy guide, Focus on WebCenter. More helpful links: * Oracle OpenWorld* Oracle Customer Experience Summit @ OpenWorld* Oracle OpenWorld on Facebook * Oracle OpenWorld on Twitter* Oracle OpenWorld on LinkedIn* Oracle OpenWorld Blog

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• Your thoughts on Best Practices for Scientific Computing?

  - by John Smith

  A recent paper by Wilson et al (2014) pointed out 24 Best Practices for scientific programming. It's worth to have a look. I would like to hear opinions about these points from experienced programmers in scientific data analysis. Do you think these advices are helpful and practical? Or are they good only in an ideal world? Wilson G, Aruliah DA, Brown CT, Chue Hong NP, Davis M, Guy RT, Haddock SHD, Huff KD, Mitchell IM, Plumbley MD, Waugh B, White EP, Wilson P (2014) Best Practices for Scientific Computing. PLoS Biol 12:e1001745. http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1001745 Box 1. Summary of Best Practices Write programs for people, not computers. (a) A program should not require its readers to hold more than a handful of facts in memory at once. (b) Make names consistent, distinctive, and meaningful. (c) Make code style and formatting consistent. Let the computer do the work. (a) Make the computer repeat tasks. (b) Save recent commands in a file for re-use. (c) Use a build tool to automate workflows. Make incremental changes. (a) Work in small steps with frequent feedback and course correction. (b) Use a version control system. (c) Put everything that has been created manually in version control. Don’t repeat yourself (or others). (a) Every piece of data must have a single authoritative representation in the system. (b) Modularize code rather than copying and pasting. (c) Re-use code instead of rewriting it. Plan for mistakes. (a) Add assertions to programs to check their operation. (b) Use an off-the-shelf unit testing library. (c) Turn bugs into test cases. (d) Use a symbolic debugger. Optimize software only after it works correctly. (a) Use a profiler to identify bottlenecks. (b) Write code in the highest-level language possible. Document design and purpose, not mechanics. (a) Document interfaces and reasons, not implementations. (b) Refactor code in preference to explaining how it works. (c) Embed the documentation for a piece of software in that software. Collaborate. (a) Use pre-merge code reviews. (b) Use pair programming when bringing someone new up to speed and when tackling particularly tricky problems. (c) Use an issue tracking tool. I'm relatively new to serious programming for scientific data analysis. When I tried to write code for pilot analyses of some of my data last year, I encountered tremendous amount of bugs both in my code and data. Bugs and errors had been around me all the time, but this time it was somewhat overwhelming. I managed to crunch the numbers at last, but I thought I couldn't put up with this mess any longer. Some actions must be taken. Without a sophisticated guide like the article above, I started to adopt "defensive style" of programming since then. A book titled "The Art of Readable Code" helped me a lot. I deployed meticulous input validations or assertions for every function, renamed a lot of variables and functions for better readability, and extracted many subroutines as reusable functions. Recently, I introduced Git and SourceTree for version control. At the moment, because my co-workers are much more reluctant about these issues, the collaboration practices (8a,b,c) have not been introduced. Actually, as the authors admitted, because all of these practices take some amount of time and effort to introduce, it may be generally hard to persuade your reluctant collaborators to comply them. I think I'm asking your opinions because I still suffer from many bugs despite all my effort on many of these practices. Bug fix may be, or should be, faster than before, but I couldn't really measure the improvement. Moreover, much of my time has been invested on defence, meaning that I haven't actually done much data analysis (offence) these days. Where is the point I should stop at in terms of productivity? I've already deployed: 1a,b,c, 2a, 3a,b,c, 4b,c, 5a,d, 6a,b, 7a,7b I'm about to have a go at: 5b,c Not yet: 2b,c, 4a, 7c, 8a,b,c (I could not really see the advantage of using GNU make (2c) for my purpose. Could anyone tell me how it helps my work with MATLAB?)

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• SQL SERVER – Service Broker and CAP_CPU_PERCENT – Limiting SQL Server Instances to CPU Usage

  - by pinaldave

  I have mentioned several times on this blog that the best part of blogging is the questions I receive from readers. They are often very interesting. The questions from readers give me a good idea what other readers might be thinking as well. After reading my earlier article Simple Example to Configure Resource Governor – Introduction to Resource Governor – I received an email from a reader and we exchanged a few emails. After exchanging emails we both figured out what is going on. It was indeed interesting and reader suggested to that I should blog about it.  I asked for permission to publish his name but he does not like the attention so we will just call him Jeff. I have converted our emails into chat for easy consumption. Jeff: Your script does not work at all. I think either there is a bug in SQL Server. Pinal: Would you please explain in detail? Jeff: Your code does not limit the CPU usage? Pinal: How did you measure it? Jeff: Well, we have third party tools for it but let us say I have limited the resources for Reporting Services and used your script described in your blog. After that I ran only reporting service workload the CPU is still used more than 100% and it is not limited to 30% as described in your script. Clearly something is wrong somewhere. Pinal: Did you say you ONLY ran reporting server load? Jeff: Yeah, to validate I ran ONLY reporting server load and CPU did not throttle at 30% as per your script. Pinal: Oh! I get it here is the answer - CAP_CPU_PERCENT = 30. Use it. Jeff: What is that, I think your earlier script says it will throttle the Reporting Service workload and Application/OLTP workload and balance it. Pinal: Exactly, that is correct. Jeff: You need to write more in email buddy! Just like your blogs, your answers do not make sense! No Offense! Pinal: Hmm…feedback well taken. Let me try again. In SQL Server 2012 there are a few enhancements with regards to SQL Server Resource Governor. One of the enhancement is how the resources are allocated. Let me explain you with examples. Configuration: [Read Earlier Post] Reporting Workload: MIN_CPU_PERCENT=0, MAX_CPU_PERCENT=30 Application/OLTP Workload: MIN_CPU_PERCENT=50, MAX_CPU_PERCENT=100 Example 1: If there is only Reporting Workload on the server: SQL Server will not limit usage of CPU to only 30% workload but SQL Server instance will use all available CPU (if needed). In another word in this scenario it will use more than 30% CPU. Example 2: If there is Reproting Workload and heavy Application/OLTP workload: SQL Server will allocate a maximum of 30% CPU resources to Reporting Workload and allocate remaining resources to heavy application/OLTP workload. The reason for this enhancement is for better utilization of the resources. Let us think, if there is only single workload, which we have limited to max CPU usage to 30%. The other unused available CPU resources is now wasted. In this situation SQL Server allows the workload to use more than 30% resources leading to overall improved/optimized performance. However, in the case of multiple workload where lots of resources are needed the limits specified in MAX_CPU_PERCENT are acknowledged. Example 3: If there is a situation where the max CPU workload has to be enforced: This is a very interesting scenario, in the case when the max CPU workload has to be enforced irrespective of the workload and enhanced algorithm, the keyword CAP_CPU_PERCENT is essential. It specifies a hard cap on the CPU bandwidth that all requests in the resource pool will receive. It will never let CPU usage for reporting workload to go over 30% in our case. You can use the key word as follows: -- Creating Resource Pool for Report Server CREATE RESOURCE POOL ReportServerPool WITH ( MIN_CPU_PERCENT=0, MAX_CPU_PERCENT=30, CAP_CPU_PERCENT=40, MIN_MEMORY_PERCENT=0, MAX_MEMORY_PERCENT=30) GO Notice that there is MAX_CPU_PERCENT=30 and CAP_CPU_PERCENT=40, what it means is that when SQL Server Instance is under heavy load under different workload it will use the maximum CPU at 30%. However, when the SQL Server instance is not under workload it will go over the 30% limit. However, as CAP_CPU_PERCENT is set to 40, it will not go over 40% in any case by limiting the usage of CPU. CAP_CPU_PERCENT puts a hard limit on the resources usage by workload. Jeff: Nice Pinal, you should blog about it. [A day passes by] Pinal: Jeff, it is done! Click here to read it. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Service Broker

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• Oracle Unveils Industry’s Broadest Cloud Strategy

  - by kellsey.ruppel

  Oracle Unveils Industry’s Broadest Cloud Strategy Adds Social Cloud and Showcases early customers Redwood Shores, Calif. – June 6, 2012 “Almost seven years of relentless engineering and innovation plus key strategic acquisitions. An investment of billions. We are now announcing the most comprehensive Cloud on the planet Earth,” said Oracle CEO, Larry Ellison. “Most cloud vendors only have niche assets. They don’t have platforms to extend. Oracle is the only vendor that offers a complete suite of modern, socially-enabled applications, all based on a standards-based platform.” News Facts In a major strategy update today, Larry Ellison announced the industry’s broadest and most advanced Cloud strategy and introduced Oracle Cloud Social Services, a broad Enterprise Social Platform offering. Oracle Cloud delivers a broad set of industry-standards based, integrated services that provide customers with subscription-based access to Oracle Platform Services, Application Services, and Social Services, all completely managed, hosted and supported by Oracle. Offering a wide range of business applications and platform services, the Oracle Cloud is the only cloud to enable customers to avoid the data and business process fragmentation that occurs when using multiple, siloed public clouds. Oracle Cloud is powered by leading enterprise-grade infrastructure, including Oracle Exadata and Oracle Exalogic, providing customers and partners with a high-performance, reliable, and secure infrastructure for running critical business applications. Oracle Cloud enables easy self-service for both business users and developers. Business users can order, configure, extend, and monitor their applications. Developers and administrators can easily develop, deploy, monitor and manage their applications. As part of the event, Oracle also showcased several early Oracle Cloud customers and partners including system integrators and independent software vendors. Oracle Cloud Platform Services Built on a common, complete, standards-based and enterprise-grade set of infrastructure components, Oracle Cloud Platform Services enable customers to speed time to market and lower costs by quickly building, deploying and managing bespoke applications. Oracle Cloud Platform Services will include: Database Services to manage data and build database applications with the Oracle Database. Java Services to develop, deploy and manage Java applications with Oracle WebLogic. Developer Services to allow application developers to collaboratively build applications. Web Services to build Web applications rapidly using PHP, Ruby, and Python. Mobile Services to allow developers to build cross-platform native and HTML5 mobile applications for leading smartphones and tablets. Documents Services to allow project teams to collaborate and share documents through online workspaces and portals. Sites Services to allow business users to develop and maintain visually engaging .com sites Analytics Services to allow business users to quickly build and share analytic dashboards and reports through the Cloud. Oracle Cloud Application Services Oracle Cloud Application Services provides customers access to the industry’s broadest range of enterprise applications available in the cloud today, with built-in business intelligence, social and mobile capabilities. Easy to setup, configure, extend, use and administer, Oracle Cloud Application Services will include: ERP Services: A complete set of Financial Accounting, Project Management, Procurement, Sourcing, and Governance, Risk & Compliance solutions. HCM Services: A complete Human Capital Management solution including Global HR, Workforce Lifecycle Management, Compensation, Benefits, Payroll and other solutions. Talent Management Services: A complete Talent Management solution including Recruiting, Sourcing, Performance Management, and Learning. Sales and Marketing Services: A complete Sales and Marketing solution including Sales Planning, Territory Management, Leads & Opportunity Management, and Forecasting. Customer Experience Services: A complete Customer Service solution including Web Self-Service, Contact Centers, Knowledge Management, Chat, and e-mail Management. Oracle Cloud Social Services Oracle Cloud Social Services provides the most broad and complete enterprise social platform available in the cloud today.  With Oracle Cloud Social Services, enterprises can engage with their customers on a range of social media properties in a comprehensive and meaningful fashion including social marketing, commerce, service and listening. The platform also provides enterprises with a rich social networking solution for their employees to collaborate effectively inside the enterprise. Oracle’s integrated social platform will include: Oracle Social Network to enable secure enterprise collaboration and purposeful social networking for business. Oracle Social Data Services to aggregate data from social networks and enterprise data sources to enrich business applications. Oracle Social Marketing and Engagement Services to enable marketers to centrally create, publish, moderate, manage, measure and report on their social marketing campaigns. Oracle Social Intelligence Services to enable marketers to analyze social media interactions and to enable customer service and sales teams to engage with customers and prospects effectively. Supporting Resources Oracle Cloud – learn more cloud.oracle.com – sign up now Webcast – watch the replay About Oracle Oracle engineers hardware and software to work together in the cloud and in your data center. For more information about Oracle (NASDAQ:ORCL), visit www.oracle.com. TrademarksOracle and Java are registered trademarks of Oracle and/or its affiliates. Other names may be trademarks of their respective owners.

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• Information Indepth Newsletter - Linux Edition

  - by Paulo Folgado

  INFORMATION INDEPTH NEWSLETTERLinux Edition February 2011 Stay Connected:  NEWS Now Available: Oracle Linux 6 Get the latest release of Oracle Linux 6, which includes Unbreakable Enterprise Kernel.Download Oracle Linux 6 Read More Customers Succeed by Using Oracle Exadata with Oracle Linux Watch IT executives from Bank of America, Linkshare, and Johns Hopkins as they talk about the business challenges they faced and why they chose to use Oracle Linux along with Oracle Exadata as the solution. Watch Now Video Interview: Oracle Senior Vice President Wim Coekaerts Watch Wim Coekaerts, senior vice president, Linux and Virtualization Engineering, as he talks about use cases for Oracle VM Templates as well as the Unbreakable Enterprise Kernel for Linux.Watch Now Hot Off the Press: Migrate Your IBM AIX Environment to Oracle Linux This new white paper provides recommendations for planning and implementing the migration of applications from an IBM Power System running AIX to Oracle's Sun Fire X4800 Server with Intel Xeon 7560 Processor running Oracle Linux 5.5.Read More  Back to Top BLOGOSPHERE Just Launched: The Oracle Linux Blog Follow our new Oracle Linux blog  to hear the latest updates, product news, upcoming events, and all the latest happenings, directly from the Linux team at Oracle. Back to Top TECH DIVE NEW: Linux/Oracle Solaris CommandComparo Site from Oracle Technology NetworkThis site gives equivalent command syntax in Oracle Solaris 10 and Oracle Enterprise Linux 5 for common administrative tasks--focusing particularly on tasks that have tricky syntax or that you frequently need to double check. It acts as a quick reference for administrators who operate in these two OS environments. Free Download: Oracle Linux Release 5.6Did you know that by using Oracle Linux 5.5 or 5.6 along with the Unbreakable Enterprise Kernel, you can get all the benefits of Linux mainline kernel 2.6.32 and more, right now, without the need to reinstall or migrate to a new operating system such as RHEL6?Read Release NotesDownload Oracle Linux 5.6 LSB 4.0 Certification Completed for Oracle Linux 5.5Oracle Linux 5.5 with Unbreakable Enterprise Kernel successfully completed the LSB 4.0 certification.  Back to Top WEBCASTS Boost Your Linux Performance with Oracle's Enhancements in Infiniband and RDSRegister to hear Director of Kernel Engineering Chris Mason cover scalability and performance improvements in Linux environment. Get the Facts Oracle's Unbreakable Enterprise KernelSVP Wim Coekaerts and Senior Director Monica Kumar cover the facts about and benefits of using Unbreakable Enterprise Kernel.  View Other Webcasts on Demand   Back to Top EVENTS Collaborate 2011April 10-14 Orlando, Florida Cloud Summit Events, WorldwideVarious dates (check the city for date/time of event) Datacenter Efficiency Events WorldwideThese events include Linux and Oracle VM sessions.Various dates (check the city for date/time of event) Virtualization Events in North America Find an Oracle Event  Back to Top EDUCATION Get Oracle Linux Certified from Oracle University Oracle University offers courses in both Oracle Linux and the administration of Oracle Database on Linux.  Back to Top CUSTOMER SPOTLIGHT Pella Corporation Improves IT Performance and Efficiency with Oracle Linux and Oracle VM To improve IT performance and efficiency and lower operational costs, Pella Corporation, has standardized on Oracle VM and Oracle Linux. Read More Disney Store Deploys POS in 330 Stores and 7 Countries on Oracle Linux Disney Store is running 1,500 registers worldwide on a broad Oracle technology software stack including Oracle Database 11g, Oracle Fusion Middleware, and Oracle Linux. Read More Back to Top PARTNER SPOTLIGHT Emulex and Oracle Announce Data Integrity Features The Unbreakable Enterprise Kernel provides data integrity checking between Oracle Database applications and Emulex 8Gb/s LightPulse Fibre Channel Host Bus Adapters. Read More Dell Inc. Dell Inc. tested and validated configurations support Oracle Linux. Back to Top STAY IN TOUCH Follow @ORCL_Linux on Twitter for the latest penguin tweets Bookmark Oracle.com/Linux Read the Oracle Linux blog Back to Top  Oracle Information InDepth newsletters bring targeted news, articles, customer stories, and special offers to business people who want to find out how to streamline enterprise information management, measure results, improve business processes, and communicate a single truth to their constituents. Please send questions or comments to [email protected]. For answers to questions about subscribing, unsubscribing, and managing your Oracle e-mail communications preferences, please see the Oracle E-Mail Communications page. Copyright © 2011, Oracle Corporation and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. This document is provided for information purposes only, and the contents hereof are subject to change without notice. This document is not warranted to be error-free, nor is it subject to any other warranties or conditions, whether expressed orally or implied in law, including implied warranties and conditions of merchantability or fitness for a particular purpose. We specifically disclaim any liability with respect to this document, and no contractual obligations are formed either directly or indirectly by this document. This document may not be reproduced or transmitted in any form or by any means, electronic or mechanical, for any purpose, without our prior written permission. 

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• Troubleshooting High-CPU Utilization for SQL Server

  - by Susantha Bathige

  The objective of this FAQ is to outline the basic steps in troubleshooting high CPU utilization on  a server hosting a SQL Server instance. The first and the most common step if you suspect high CPU utilization (or are alerted for it) is to login to the physical server and check the Windows Task Manager. The Performance tab will show the high utilization as shown below: Next, we need to determine which process is responsible for the high CPU consumption. The Processes tab of the Task Manager will show this information: Note that to see all processes you should select Show processes from all user. In this case, SQL Server (sqlserver.exe) is consuming 99% of the CPU (a normal benchmark for max CPU utilization is about 50-60%). Next we examine the scheduler data. Scheduler is a component of SQLOS which evenly distributes load amongst CPUs. The query below returns the important columns for CPU troubleshooting. Note – if your server is under severe stress and you are unable to login to SSMS, you can use another machine’s SSMS to login to the server through DAC – Dedicated Administrator Connection (see http://msdn.microsoft.com/en-us/library/ms189595.aspx for details on using DAC) SELECT scheduler_id ,cpu_id ,status ,runnable_tasks_count ,active_workers_count ,load_factor ,yield_count FROM sys.dm_os_schedulers WHERE scheduler_id See below for the BOL definitions for the above columns. scheduler_id – ID of the scheduler. All schedulers that are used to run regular queries have ID numbers less than 1048576. Those schedulers that have IDs greater than or equal to 1048576 are used internally by SQL Server, such as the dedicated administrator connection scheduler. cpu_id – ID of the CPU with which this scheduler is associated. status – Indicates the status of the scheduler. runnable_tasks_count – Number of workers, with tasks assigned to them that are waiting to be scheduled on the runnable queue. active_workers_count – Number of workers that are active. An active worker is never preemptive, must have an associated task, and is either running, runnable, or suspended. current_tasks_count - Number of current tasks that are associated with this scheduler. load_factor – Internal value that indicates the perceived load on this scheduler. yield_count – Internal value that is used to indicate progress on this scheduler.                                                                 Now to interpret the above data. There are four schedulers and each assigned to a different CPU. All the CPUs are ready to accept user queries as they all are ONLINE. There are 294 active tasks in the output as per the current_tasks_count column. This count indicates how many activities currently associated with the schedulers. When a  task is complete, this number is decremented. The 294 is quite a high figure and indicates all four schedulers are extremely busy. When a task is enqueued, the load_factor  value is incremented. This value is used to determine whether a new task should be put on this scheduler or another scheduler. The new task will be allocated to less loaded scheduler by SQLOS. The very high value of this column indicates all the schedulers have a high load. There are 268 runnable tasks which mean all these tasks are assigned a worker and waiting to be scheduled on the runnable queue.   The next step is  to identify which queries are demanding a lot of CPU time. The below query is useful for this purpose (note, in its current form,  it only shows the top 10 records). SELECT TOP 10 st.text  ,st.dbid  ,st.objectid  ,qs.total_worker_time  ,qs.last_worker_time  ,qp.query_plan FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) st CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle) qp ORDER BY qs.total_worker_time DESC This query as total_worker_time as the measure of CPU load and is in descending order of the  total_worker_time to show the most expensive queries and their plans at the top:      Note the BOL definitions for the important columns: total_worker_time - Total amount of CPU time, in microseconds, that was consumed by executions of this plan since it was compiled. last_worker_time - CPU time, in microseconds, that was consumed the last time the plan was executed.   I re-ran the same query again after few seconds and was returned the below output. After few seconds the SP dbo.TestProc1 is shown in fourth place and once again the last_worker_time is the highest. This means the procedure TestProc1 consumes a CPU time continuously each time it executes.      In this case, the primary cause for high CPU utilization was a stored procedure. You can view the execution plan by clicking on query_plan column to investigate why this is causing a high CPU load. I have used SQL Server 2008 (SP1) to test all the queries used in this article.

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• SQL SERVER – Fundamentals of Columnstore Index

  - by pinaldave

  There are two kind of storage in database. Row Store and Column Store. Row store does exactly as the name suggests – stores rows of data on a page – and column store stores all the data in a column on the same page. These columns are much easier to search – instead of a query searching all the data in an entire row whether the data is relevant or not, column store queries need only to search much lesser number of the columns. This means major increases in search speed and hard drive use. Additionally, the column store indexes are heavily compressed, which translates to even greater memory and faster searches. I am sure this looks very exciting and it does not mean that you convert every single index from row store to column store index. One has to understand the proper places where to use row store or column store indexes. Let us understand in this article what is the difference in Columnstore type of index. Column store indexes are run by Microsoft’s VertiPaq technology. However, all you really need to know is that this method of storing data is columns on a single page is much faster and more efficient. Creating a column store index is very easy, and you don’t have to learn new syntax to create them. You just need to specify the keyword “COLUMNSTORE” and enter the data as you normally would. Keep in mind that once you add a column store to a table, though, you cannot delete, insert or update the data – it is READ ONLY. However, since column store will be mainly used for data warehousing, this should not be a big problem. You can always use partitioning to avoid rebuilding the index. A columnstore index stores each column in a separate set of disk pages, rather than storing multiple rows per page as data traditionally has been stored. The difference between column store and row store approaches is illustrated below: In case of the row store indexes multiple pages will contain multiple rows of the columns spanning across multiple pages. In case of column store indexes multiple pages will contain multiple single columns. This will lead only the columns needed to solve a query will be fetched from disk. Additionally there is good chance that there will be redundant data in a single column which will further help to compress the data, this will have positive effect on buffer hit rate as most of the data will be in memory and due to same it will not need to be retrieved. Let us see small example of how columnstore index improves the performance of the query on a large table. As a first step let us create databaseset which is large enough to show performance impact of columnstore index. The time taken to create sample database may vary on different computer based on the resources. USE AdventureWorks GO -- Create New Table CREATE TABLE [dbo].[MySalesOrderDetail]( [SalesOrderID] [int] NOT NULL, [SalesOrderDetailID] [int] NOT NULL, [CarrierTrackingNumber] [nvarchar](25) NULL, [OrderQty] [smallint] NOT NULL, [ProductID] [int] NOT NULL, [SpecialOfferID] [int] NOT NULL, [UnitPrice] [money] NOT NULL, [UnitPriceDiscount] [money] NOT NULL, [LineTotal] [numeric](38, 6) NOT NULL, [rowguid] [uniqueidentifier] NOT NULL, [ModifiedDate] [datetime] NOT NULL ) ON [PRIMARY] GO -- Create clustered index CREATE CLUSTERED INDEX [CL_MySalesOrderDetail] ON [dbo].[MySalesOrderDetail] ( [SalesOrderDetailID]) GO -- Create Sample Data Table -- WARNING: This Query may run upto 2-10 minutes based on your systems resources INSERT INTO [dbo].[MySalesOrderDetail] SELECT S1.* FROM Sales.SalesOrderDetail S1 GO 100 Now let us do quick performance test. I have kept STATISTICS IO ON for measuring how much IO following queries take. In my test first I will run query which will use regular index. We will note the IO usage of the query. After that we will create columnstore index and will measure the IO of the same. -- Performance Test -- Comparing Regular Index with ColumnStore Index USE AdventureWorks GO SET STATISTICS IO ON GO -- Select Table with regular Index SELECT ProductID, SUM(UnitPrice) SumUnitPrice, AVG(UnitPrice) AvgUnitPrice, SUM(OrderQty) SumOrderQty, AVG(OrderQty) AvgOrderQty FROM [dbo].[MySalesOrderDetail] GROUP BY ProductID ORDER BY ProductID GO -- Table 'MySalesOrderDetail'. Scan count 1, logical reads 342261, physical reads 0, read-ahead reads 0. -- Create ColumnStore Index CREATE NONCLUSTERED COLUMNSTORE INDEX [IX_MySalesOrderDetail_ColumnStore] ON [MySalesOrderDetail] (UnitPrice, OrderQty, ProductID) GO -- Select Table with Columnstore Index SELECT ProductID, SUM(UnitPrice) SumUnitPrice, AVG(UnitPrice) AvgUnitPrice, SUM(OrderQty) SumOrderQty, AVG(OrderQty) AvgOrderQty FROM [dbo].[MySalesOrderDetail] GROUP BY ProductID ORDER BY ProductID GO It is very clear from the results that query is performance extremely fast after creating ColumnStore Index. The amount of the pages it has to read to run query is drastically reduced as the column which are needed in the query are stored in the same page and query does not have to go through every single page to read those columns. If we enable execution plan and compare we can see that column store index performance way better than regular index in this case. Let us clean up the database. -- Cleanup DROP INDEX [IX_MySalesOrderDetail_ColumnStore] ON [dbo].[MySalesOrderDetail] GO TRUNCATE TABLE dbo.MySalesOrderDetail GO DROP TABLE dbo.MySalesOrderDetail GO In future posts we will see cases where Columnstore index is not appropriate solution as well few other tricks and tips of the columnstore index. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Index, SQL Optimization, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• MDX using EXISTING, AGGREGATE, CROSSJOIN and WHERE

  - by James Rogers

  It is a well-published approach to using the EXISTING function to decode AGGREGATE members and nested sub-query filters.  Mosha wrote a good blog on it here and a more recent one here.  The use of EXISTING in these scenarios is very useful and sometimes the only option when dealing with multi-select filters.  However, there are some limitations I have run across when using the EXISTING function against an AGGREGATE member:   The AGGREGATE member must be assigned to the Dimension.Hierarchy being detected by the EXISTING function in the calculated measure. The AGGREGATE member cannot contain a crossjoin from any other dimension or hierarchy or EXISTING will not be able to detect the members in the AGGREGATE member.   Take the following query (from Adventure Works DW 2008):   With   member [Week Count] as 'count(existing([Date].[Fiscal Weeks].[Fiscal Week].members))'    member [Date].[Fiscal Weeks].[CM] as 'AGGREGATE({[Date].[Fiscal Weeks].[Fiscal Week].&[47]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[48]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[49]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[50]&[2004]})'   select   {[Week Count]} on columns from   [Adventure Works]     where   [Date].[Fiscal Weeks].[CM]   Here we are attempting to count the existing fiscal weeks in slicer.  This is useful to get a per-week average for another member. Many applications generate queries in this manner (such as Oracle OBIEE).  This query returns the correct result of (4) weeks. Now let's put a twist in it.  What if the querying application submits the query in the following manner:   With   member [Week Count] as 'count(existing([Date].[Fiscal Weeks].[Fiscal Week].members))'    member [Customer].[Customer Geography].[CM] as 'AGGREGATE({[Date].[Fiscal Weeks].[Fiscal Week].&[47]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[48]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[49]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[50]&[2004]})'   select   {[Week Count]} on columns from   [Adventure Works]     where   [Customer].[Customer Geography].[CM]   Here we are attempting to count the existing fiscal weeks in slicer.  However, the AGGREGATE member is built on a different dimension (in name) than the one EXISTING is trying to detect.  In this case the query returns (174) which is the total number of [Date].[Fiscal Weeks].[Fiscal Week].members defined in the dimension.   Now another twist, the AGGREGATE member will be named appropriately and contain the hierarchy we are trying to detect with EXISTING but it will be cross-joined with another hierarchy:   With   member [Week Count] as 'count(existing([Date].[Fiscal Weeks].[Fiscal Week].members))'    member [Date].[Fiscal Weeks].[CM] as 'AGGREGATE({[Date].[Fiscal Weeks].[Fiscal Week].&[47]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[48]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[49]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[50]&[2004]}*    {[Customer].[Customer Geography].[Country].&[Australia],[Customer].[Customer Geography].[Country].&[United States]})'  select   {[Week Count]} on columns from   [Adventure Works]    where   [Date].[Fiscal Weeks].[CM]   Once again, we are attempting to count the existing fiscal weeks in slicer.  Again, in this case the query returns (174) which is the total number of [Date].[Fiscal Weeks].[Fiscal Week].members defined in the dimension. However, in 2008 R2 this query returns the correct result of 4 and additionally , the following will return the count of existing countries as well (2):   With   member [Week Count] as 'count(existing([Date].[Fiscal Weeks].[Fiscal Week].members))'   member [Country Count] as 'count(existing([Customer].[Customer Geography].[Country].members))'  member [Date].[Fiscal Weeks].[CM] as 'AGGREGATE({[Date].[Fiscal Weeks].[Fiscal Week].&[47]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[48]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[49]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[50]&[2004]}*    {[Customer].[Customer Geography].[Country].&[Australia],[Customer].[Customer Geography].[Country].&[United States]})'  select   {[Week Count]} on columns from   [Adventure Works]    where   [Date].[Fiscal Weeks].[CM]   2008 R2 seems to work as long as the AGGREGATE member is on at least one of the hierarchies attempting to be detected (i.e. [Date].[Fiscal Weeks] or [Customer].[Customer Geography]). If not, it seems that the engine cannot find a "point of entry" into the aggregate member and ignores it for calculated members.   One way around this would be to put the sets from the AGGREGATE member explicitly in the WHERE clause (slicer).  I realize this is only supported in SSAS 2005 and 2008.  However, after talking with Chris Webb (his blog is here and I highly recommend following his efforts and musings) it is a far more efficient way to filter/slice a query:   With   member [Week Count] as 'count(existing([Date].[Fiscal Weeks].[Fiscal Week].members))'    select   {[Week Count]} on columns from   [Adventure Works]    where   ({[Date].[Fiscal Weeks].[Fiscal Week].&[47]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[48]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[49]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[50]&[2004]}   ,{[Customer].[Customer Geography].[Country].&[Australia],[Customer].[Customer Geography].[Country].&[United States]})   This query returns the correct result of (4) weeks.  Additionally, we can count the cross-join members of the two hierarchies in the slicer:   With   member [Week Count] as 'count(existing([Date].[Fiscal Weeks].[Fiscal Week].members)*existing([Customer].[Customer Geography].[Country].members))'    select   {[Week Count]} on columns from   [Adventure Works]    where   ({[Date].[Fiscal Weeks].[Fiscal Week].&[47]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[48]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[49]&[2004],[Date].[Fiscal Weeks].[Fiscal Week].&[50]&[2004]}   ,{[Customer].[Customer Geography].[Country].&[Australia],[Customer].[Customer Geography].[Country].&[United States]})   We get the correct number of (8) here.

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• Oracle’s Web Experience Management

  - by Christie Flanagan

  Today’s guest post on Oracle’s Web Experience Management comes from a member of our WebCenter Evangelist team, Noël Jaffré, a Principal Technologist based in France.Oracle’s Web Experience Management (WEM) solution enables organizations to optimize the online channel for driving marketing and customer experience management success. It empowers business users to manage the web presence and create rich and engaging online experiences for customers and prospects. Oracle's WEM platform provides a framework to simplify the integration of Oracle, third-party and custom-built applications. This framework essentially allows the creation and integration of applications using one single business interface called the WEM interface. It includes the following: Single sign-on access control for all integrated applications using the Central Authentication Service (CAS) component. A single centralized administration window for user, role, and native applications management including site management. Community server management, gadget server management as well as management for partner integrated technologies. A Representational State Transfer (REST) API for accessing WebCenter Sites data. REST services are supported on both Oracle WebCenter Sites and Oracle WebCenter Sites Satellite Server to leverage the satellite server cache. All REST requests are cached for web consuming applications as well for the high performance delivery of native applications on the mobile channel. Oracle WebCenter Sites’ Web Experience Management environment enables organizations to deliver a compelling online experience to customers by simplifying the deployment and management of sophisticated and engaging websites. The WebCenter Sites platform automates the entire process of managing web content including: Authoring:  Business users can easily contribute and manage web content in real-time, with intuitive interfaces and drag-and-drop content authoring and layout capabilities designed for the non-technical user. Contextual Content Targeting: Marketers are empowered to create and manage targeted campaigns with relevant recommendations and promotions based on the context of the session of the visitor such as his or her navigation history, user profile, language, location or other information shared during the visitor session. Content Publishing and Deployment: It offers advanced multi-site management capabilities for departmental or regional sites, as well as strong multi-lingual and multi-locale content management. The remote satellite server caching infrastructure provides high-performance, distributed caching, tuned to deliver high-volume, targeted and multi-lingual sites. Analytics and Optimization: Business users and marketers have the ability to measure the effectiveness of their online content and campaigns at a granular level. Editors and marketers can immediately determine whether a given article or promotion is relevant to a particular customer segment. User-generated Content: Marketers can enable blogs, comments, rating and reviews on the website.  All comments and reviews posted to the website can be moderated from the administrator interface either manually or automatically using filters, whitelists, blacklists or community based moderation. Personalized Gadget Dashboards:  Site managers can deploy gadgets, small applications using web content, individually or as part of dashboards containing multiple gadgets.  These gadget dashboards enable site visitors to create their own “MyPage” on a given site where they can select and customize the gadgets that the site administrator has made available.  Any gadget that conforms to the iGoogle/OpenSocial standard can be made available to site visitors, or they can be created within the WEM interface. Oracle's WEM platform also provides a unique environment for the delivery of a rich, multichannel online experience for site visitors through its advanced management modules for mobile. With Oracle’s WEM solution, it’s easy to control branding and deliver a consistent message while repurposing web content for publication to mobile devices, kiosks and much more. This distinctive approach provides: HTML5 Delivery: HTML5 delivery which includes native support for adaptive design that responds to the user’s computer screen resolution and orientation. The approach is less driven by the particular hardware and more driven by the user’s interactions with the device. In other words, this approach takes both the screen interactions (either cursor or touch) and screen sizes and orientation into consideration. A Unique Native Mobile Extension Environment for Contributors: From the WEM interface, a contributor can directly manage their mobile channel, using the tooling already in place for driving the traditional web presence. This includes the mobile presentation, as well as mobile insite editing, drag and drop page layout, and in-context recommendations and personalization. Optimized REST APIs for High Performance Content Delivery on Native Mobile Device Applications: WebCenter Sites’ REST API uses the underlying HTTP methods (GET, POST, PUT, DELETE) to interact with resources. Resources support two types of input and output formats -- XML and JSON. REST calls are customizable to optimize the interactions between the content repositories and the client applications. Caching is essential to decrease network loads and improve overall reliability and usability of the applications and user interactions. REST results are cached through the highly efficient Oracle WebCenter Sites caching architecture.

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• Why lock-free data structures just aren't lock-free enough

  - by Alex.Davies

  Today's post will explore why the current ways to communicate between threads don't scale, and show you a possible way to build scalable parallel programming on top of shared memory. The problem with shared memory Soon, we will have dozens, hundreds and then millions of cores in our computers. It's inevitable, because individual cores just can't get much faster. At some point, that's going to mean that we have to rethink our architecture entirely, as millions of cores can't all access a shared memory space efficiently. But millions of cores are still a long way off, and in the meantime we'll see machines with dozens of cores, struggling with shared memory. Alex's tip: The best way for an application to make use of that increasing parallel power is to use a concurrency model like actors, that deals with synchronisation issues for you. Then, the maintainer of the actors framework can find the most efficient way to coordinate access to shared memory to allow your actors to pass messages to each other efficiently. At the moment, NAct uses the .NET thread pool and a few locks to marshal messages. It works well on dual and quad core machines, but it won't scale to more cores. Every time we use a lock, our core performs an atomic memory operation (eg. CAS) on a cell of memory representing the lock, so it's sure that no other core can possibly have that lock. This is very fast when the lock isn't contended, but we need to notify all the other cores, in case they held the cell of memory in a cache. As the number of cores increases, the total cost of a lock increases linearly. A lot of work has been done on "lock-free" data structures, which avoid locks by using atomic memory operations directly. These give fairly dramatic performance improvements, particularly on systems with a few (2 to 4) cores. The .NET 4 concurrent collections in System.Collections.Concurrent are mostly lock-free. However, lock-free data structures still don't scale indefinitely, because any use of an atomic memory operation still involves every core in the system. A sync-free data structure Some concurrent data structures are possible to write in a completely synchronization-free way, without using any atomic memory operations. One useful example is a single producer, single consumer (SPSC) queue. It's easy to write a sync-free fixed size SPSC queue using a circular buffer*. Slightly trickier is a queue that grows as needed. You can use a linked list to represent the queue, but if you leave the nodes to be garbage collected once you're done with them, the GC will need to involve all the cores in collecting the finished nodes. Instead, I've implemented a proof of concept inspired by this intel article which reuses the nodes by putting them in a second queue to send back to the producer. * In all these cases, you need to use memory barriers correctly, but these are local to a core, so don't have the same scalability problems as atomic memory operations. Performance tests I tried benchmarking my SPSC queue against the .NET ConcurrentQueue, and against a standard Queue protected by locks. In some ways, this isn't a fair comparison, because both of these support multiple producers and multiple consumers, but I'll come to that later. I started on my dual-core laptop, running a simple test that had one thread producing 64 bit integers, and another consuming them, to measure the pure overhead of the queue. So, nothing very interesting here. Both concurrent collections perform better than the lock-based one as expected, but there's not a lot to choose between the ConcurrentQueue and my SPSC queue. I was a little disappointed, but then, the .NET Framework team spent a lot longer optimising it than I did. So I dug out a more powerful machine that Red Gate's DBA tools team had been using for testing. It is a 6 core Intel i7 machine with hyperthreading, adding up to 12 logical cores. Now the results get more interesting. As I increased the number of producer-consumer pairs to 6 (to saturate all 12 logical cores), the locking approach was slow, and got even slower, as you'd expect. What I didn't expect to be so clear was the drop-off in performance of the lock-free ConcurrentQueue. I could see the machine only using about 20% of available CPU cycles when it should have been saturated. My interpretation is that as all the cores used atomic memory operations to safely access the queue, they ended up spending most of the time notifying each other about cache lines that need invalidating. The sync-free approach scaled perfectly, despite still working via shared memory, which after all, should still be a bottleneck. I can't quite believe that the results are so clear, so if you can think of any other effects that might cause them, please comment! Obviously, this benchmark isn't realistic because we're only measuring the overhead of the queue. Any real workload, even on a machine with 12 cores, would dwarf the overhead, and there'd be no point worrying about this effect. But would that be true on a machine with 100 cores? Still to be solved. The trouble is, you can't build many concurrent algorithms using only an SPSC queue to communicate. In particular, I can't see a way to build something as general purpose as actors on top of just SPSC queues. Fundamentally, an actor needs to be able to receive messages from multiple other actors, which seems to need an MPSC queue. I've been thinking about ways to build a sync-free MPSC queue out of multiple SPSC queues and some kind of sign-up mechanism. Hopefully I'll have something to tell you about soon, but leave a comment if you have any ideas.

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• SPARC T4-4 Delivers World Record First Result on PeopleSoft Combined Benchmark

  - by Brian

  Oracle's SPARC T4-4 servers running Oracle's PeopleSoft HCM 9.1 combined online and batch benchmark achieved World Record 18,000 concurrent users while executing a PeopleSoft Payroll batch job of 500,000 employees in 43.32 minutes and maintaining online users response time at < 2 seconds. This world record is the first to run online and batch workloads concurrently. This result was obtained with a SPARC T4-4 server running Oracle Database 11g Release 2, a SPARC T4-4 server running PeopleSoft HCM 9.1 application server and a SPARC T4-2 server running Oracle WebLogic Server in the web tier. The SPARC T4-4 server running the application tier used Oracle Solaris Zones which provide a flexible, scalable and manageable virtualization environment. The average CPU utilization on the SPARC T4-2 server in the web tier was 17%, on the SPARC T4-4 server in the application tier it was 59%, and on the SPARC T4-4 server in the database tier was 35% (online and batch) leaving significant headroom for additional processing across the three tiers. The SPARC T4-4 server used for the database tier hosted Oracle Database 11g Release 2 using Oracle Automatic Storage Management (ASM) for database files management with I/O performance equivalent to raw devices. This is the first three tier mixed workload (online and batch) PeopleSoft benchmark also processing PeopleSoft payroll batch workload. Performance Landscape PeopleSoft HR Self-Service and Payroll Benchmark Systems Users Ave Response Search (sec) Ave Response Save (sec) Batch Time (min) Streams SPARC T4-2 (web) SPARC T4-4 (app) SPARC T4-2 (db) 18,000 0.944 0.503 43.32 64 Configuration Summary Application Configuration: 1 x SPARC T4-4 server with 4 x SPARC T4 processors, 3.0 GHz 512 GB memory 5 x 300 GB SAS internal disks 1 x 100 GB and 2 x 300 GB internal SSDs 2 x 10 Gbe HBA Oracle Solaris 11 11/11 PeopleTools 8.52 PeopleSoft HCM 9.1 Oracle Tuxedo, Version 10.3.0.0, 64-bit, Patch Level 031 Java Platform, Standard Edition Development Kit 6 Update 32 Database Configuration: 1 x SPARC T4-4 server with 4 x SPARC T4 processors, 3.0 GHz 256 GB memory 3 x 300 GB SAS internal disks Oracle Solaris 11 11/11 Oracle Database 11g Release 2 Web Tier Configuration: 1 x SPARC T4-2 server with 2 x SPARC T4 processors, 2.85 GHz 256 GB memory 2 x 300 GB SAS internal disks 1 x 100 GB internal SSD Oracle Solaris 11 11/11 PeopleTools 8.52 Oracle WebLogic Server 10.3.4 Java Platform, Standard Edition Development Kit 6 Update 32 Storage Configuration: 1 x Sun Server X2-4 as a COMSTAR head for data 4 x Intel Xeon X7550, 2.0 GHz 128 GB memory 1 x Sun Storage F5100 Flash Array (80 flash modules) 1 x Sun Storage F5100 Flash Array (40 flash modules) 1 x Sun Fire X4275 as a COMSTAR head for redo logs 12 x 2 TB SAS disks with Niwot Raid controller Benchmark Description This benchmark combines PeopleSoft HCM 9.1 HR Self Service online and PeopleSoft Payroll batch workloads to run on a unified database deployed on Oracle Database 11g Release 2. The PeopleSoft HRSS benchmark kit is a Oracle standard benchmark kit run by all platform vendors to measure the performance. It's an OLTP benchmark where DB SQLs are moderately complex. The results are certified by Oracle and a white paper is published. PeopleSoft HR SS defines a business transaction as a series of HTML pages that guide a user through a particular scenario. Users are defined as corporate Employees, Managers and HR administrators. The benchmark consist of 14 scenarios which emulate users performing typical HCM transactions such as viewing paycheck, promoting and hiring employees, updating employee profile and other typical HCM application transactions. All these transactions are well-defined in the PeopleSoft HR Self-Service 9.1 benchmark kit. This benchmark metric is the weighted average response search/save time for all the transactions. The PeopleSoft 9.1 Payroll (North America) benchmark demonstrates system performance for a range of processing volumes in a specific configuration. This workload represents large batch runs typical of a ERP environment during a mass update. The benchmark measures five application business process run times for a database representing large organization. They are Paysheet Creation, Payroll Calculation, Payroll Confirmation, Print Advice forms, and Create Direct Deposit File. The benchmark metric is the cumulative elapsed time taken to complete the Paysheet Creation, Payroll Calculation and Payroll Confirmation business application processes. The benchmark metrics are taken for each respective benchmark while running simultaneously on the same database back-end. Specifically, the payroll batch processes are started when the online workload reaches steady state (the maximum number of online users) and overlap with online transactions for the duration of the steady state. Key Points and Best Practices Two Oracle PeopleSoft Domain sets with 200 application servers each on a SPARC T4-4 server were hosted in 2 separate Oracle Solaris Zones to demonstrate consolidation of multiple application servers, ease of administration and performance tuning. Each Oracle Solaris Zone was bound to a separate processor set, each containing 15 cores (total 120 threads). The default set (1 core from first and third processor socket, total 16 threads) was used for network and disk interrupt handling. This was done to improve performance by reducing memory access latency by using the physical memory closest to the processors and offload I/O interrupt handling to default set threads, freeing up cpu resources for Application Servers threads and balancing application workload across 240 threads. See Also Oracle PeopleSoft Benchmark White Papers oracle.com SPARC T4-2 Server oracle.com OTN SPARC T4-4 Server oracle.com OTN PeopleSoft Enterprise Human Capital Management oracle.com OTN PeopleSoft Enterprise Human Capital Management (Payroll) oracle.com OTN Oracle Solaris oracle.com OTN Oracle Database 11g Release 2 Enterprise Edition oracle.com OTN Disclosure Statement Oracle's PeopleSoft HR and Payroll combined benchmark, www.oracle.com/us/solutions/benchmark/apps-benchmark/peoplesoft-167486.html, results 09/30/2012.

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• Five Things Learned at the BSR Conference in San Francisco on Nov 2nd-4th

  - by Evelyn Neumayr

  The BSR Conference 2011—“Redefining Leadership”—held from Nov 2nd to Nov 4th in San Francisco, with Oracle as one of the main sponsors, saw senior business executives, civil society representatives, and other experts from around the world gathering to share strategies and insights on the future of sustainability. The general conference sessions kicked off on November 2nd with a plenary address by former U.S. Vice President Al Gore. Other sessions were presented by CEOs of the caliber of Carl Bass (Autodesk), Brian Dunn (Best Buy), Carlos Brito (Anheuser-Busch InBev) and Ofra Strauss (Strauss Group). Here are five key highlights from the conference: 1.      The main leadership challenge is integrating sustainability into core business functions and overcoming short-termism. The “BSR GlobeScan State of Sustainable Business Poll 2011” - a survey of nearly 500 business leaders from 300 member companies - shows that 84% of respondents are optimistic that global businesses will embrace CSR/sustainability as part of their core strategies and operations in the next five years but consider integrating sustainability into their core business functions the key challenge. It is still difficult for many companies that are committed to the sustainability agenda to find investors that understand the long-term implications and as Al Gore said “Many companies are given the signal by the investors that it is the short term results that matter and that is a terribly debilitating force in the market.” 2.      Companies are required to address increasing compliance requirements and transparency in their supply chain, especially in relation with conflict minerals legislation and water management. The Dodd-Frank legislation, OECD guidelines, and the upcoming Securities and Exchange Commission (SEC) rules require companies to monitor upstream the sourcing of tin, tantalum, tungsten, and gold, but given the complexity of this issue companies need to collaborate and partner with peer companies in their industry as well as in other industries to understand how to address conflict minerals in their supply chains. The Institute of Public and Environmental Affairs’ (IPE) China Water Pollution Map enables the public to access thousands of environmental quality, discharge, and infraction records released by various government agencies. Empowered with this information, the public has the opportunity to place greater pressure on polluting companies to comply with environmental standards and create solutions to improve their performance. 3.      A new standard for reporting on supply chain greenhouse gas emissions is available. The New “Scope 3” Supply Chain Greenhouse Gas Inventory Standard, released on October 4th 2011, is the only international greenhouse gas emissions standard that accounts for the full lifecycle of a company’s products. It provides a framework for companies to account for indirect emissions outside of energy use, such as transportation, manufacturing, and distribution, and it incorporates both upstream and downstream impacts of a product. With key investors now listing supplier vulnerability to rising energy prices and disruptions of service as a key concern, greenhouse gas (GHG) management isn’t just for leading companies but a necessity for any business. 4.      Environmental, social, and corporate governance (ESG) reporting is becoming increasingly important to investors and other stakeholders. While European investors have traditionally driven the ESG agenda, U.S. investors are increasingly including ESG data in their analyses. This trend will likely increase as stakeholders continue to demand that an ESG lens be applied to their investments. Investors are increasingly looking to partner on sustainability, as they see the benefits of ESG providing significant returns on investment. 5.      Software companies are offering an increasing variety of solutions to help drive changes and measure performance internally, in supply chains, and across peer companies. The significant challenge is how to integrate different software systems to facilitate decision-making based on a holistic understanding of trade-offs. Jon Chorley, Chief Sustainability Officer and Vice President, Supply Chain Management Product Strategy at Oracle was a panelist in the “Trends in Sustainability Software” session and commented that, “How we think about our business decisions really comes down to how we think about cost. And as long as we don’t assign a cost to things that have an environmental impact or social impact, then we make decisions based on incomplete information. If we could include that in the process that determines ‘Is this product profitable? we would then have a much better decision.” For more information on BSR visit www.brs.org. You can also view highlights of the plenary session at http://www.bsr.org/en/bsr-conference/session-summaries/2011. Oracle is proud to be a sponsor of this BSR conference. By Elena Avesani, Principal Product Strategy Manager, Oracle          

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• Explaining Explain Plan Notes for Auto DOP

  - by jean-pierre.dijcks

  I've recently gotten some questions around "why do I not see a parallel plan" while Auto DOP is on (I think)...? It is probably worthwhile to quickly go over some of the ways to find out what Auto DOP was thinking. In general, there is no need to go tracing sessions and look under the hood. The thing to start with is to do an explain plan on your statement and to look at the parameter settings on the system. Parameter Settings to Look At First and foremost, make sure that parallel_degree_policy = AUTO. If you have that parameter set to LIMITED you will not have queuing and we will only do the auto magic if your objects are set to default parallel (so no degree specified). Next you want to look at the value of parallel_degree_limit. It is typically set to CPU, which in default settings equates to the Default DOP of the system. If you are testing Auto DOP itself and the impact it has on performance you may want to leave it at this CPU setting. If you are running concurrent statements you may want to give this some more thoughts. See here for more information. In general, do stick with either CPU or with a specific number. For now avoid the IO setting as I've seen some mixed results with that... In 11.2.0.2 you should also check that IO Calibrate has been run. Best to simply do a: SQL> select * from V$IO_CALIBRATION_STATUS; STATUS        CALIBRATION_TIME ------------- ---------------------------------------------------------------- READY         04-JAN-11 10.04.13.104 AM You should see that your IO Calibrate is READY and therefore Auto DOP is ready. In any case, if you did not run the IO Calibrate step you will get the following note in the explain plan: Note -----    - automatic DOP: skipped because of IO calibrate statistics are missing One more note on calibrate_io, if you do not have asynchronous IO enabled you will see:  ERROR at line 1: ORA-56708: Could not find any datafiles with asynchronous i/o capability ORA-06512: at "SYS.DBMS_RMIN", line 463 ORA-06512: at "SYS.DBMS_RESOURCE_MANAGER", line 1296 ORA-06512: at line 7 While this is changed in some fixes to the calibrate procedure, you should really consider switching asynchronous IO on for your data warehouse. Explain Plan Explanation To see the notes that are shown and explained here (and the above little snippet ) you can use a simple explain plan mechanism. There should  be no need to add +parallel etc. explain plan for <statement> SELECT PLAN_TABLE_OUTPUT FROM TABLE(DBMS_XPLAN.DISPLAY()); Auto DOP The note structure displaying why Auto DOP did not work (with the exception noted above on IO Calibrate) is like this: Automatic degree of parallelism is disabled: <reason> These are the reason codes: Parameter -  parallel_degree_policy = manual which will not allow Auto DOP to kick in  Hint - One of the following hints are used NOPARALLEL, PARALLEL(1), PARALLEL(MANUAL) Outline - A SQL outline of an older version (before 11.2) is used SQL property restriction - The statement type does not allow for parallel processing Rule-based mode - Instead of the Cost Based Optimizer the system is using the RBO Recursive SQL statement - The statement type does not allow for parallel processing pq disabled/pdml disabled/pddl disabled - For some reason (alter session?) parallelism is disabled Limited mode but no parallel objects referenced - your parallel_degree_policy = LIMITED and no objects in the statement are decorated with the default PARALLEL degree. In most cases all objects have a specific degree in which case Auto DOP will honor that degree. Parallel Degree Limited When Auto DOP does it works you may see the cap you imposed with parallel_degree_limit showing up in the note section of the explain plan: Note -----    - automatic DOP: Computed Degree of Parallelism is 16 because of degree limit This is an obvious indication that your are being capped for this statement. There is one quite interesting one that happens when you are being capped at DOP = 1. First of you get a serial plan and the note changes slightly in that it does not indicate it is being capped (we hope to update the note at some point in time to be more specific). It right now looks like this: Note -----    - automatic DOP: Computed Degree of Parallelism is 1 Dynamic Sampling With 11.2.0.2 you will start seeing another interesting change in parallel plans, and since we are talking about the note section here, I figured we throw this in for good measure. If we deem the parallel (!) statement complex enough, we will enact dynamic sampling on your query. This happens as long as you did not change the default for dynamic sampling on the system. The note looks like this: Note ----- - dynamic sampling used for this statement (level=5)

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• Adventures in Windows 8: Understanding and debugging design time data in Expression Blend

  - by Laurent Bugnion

  One of my favorite features in Expression Blend is the ability to attach a Visual Studio debugger to Blend. First let’s start by answering the question: why exactly do you want to do that? Note: If you are familiar with the creation and usage of design time data, feel free to scroll down to the paragraph titled “When design time data fails”. Creating design time data for your app When a designer works on an app, he needs to see something to design. For “static” UI such as buttons, backgrounds, etc, the user interface elements are going to show up in Blend just fine. If however the data is fetched dynamically from a service (web, database, etc) or created dynamically, most probably Blend is going to show just an empty element. The classical way to design at that stage is to run the application, navigate to the screen that is under construction (which can involve delays, need to log in, etc…), to measure what is on the screen (colors, margins, width and height, etc) using various tools, going back to Blend, editing the properties of the elements, running again, etc. Obviously this is not ideal. The solution is to create design time data. For more information about the creation of design time data by mocking services, you can refer to two talks of mine “Deep dive MVVM” and “MVVM Applied From Silverlight to Windows Phone to Windows 8”. The source code for these talks is here and here. Design time data in MVVM Light One of the main reasons why I developed MVVM Light is to facilitate the creation of design time data. To illustrate this, let’s create a new MVVM Light application in Visual Studio. Install MVVM Light from here: http://mvvmlight.codeplex.com (use the MSI in the Download section). After installing, make sure to read the Readme that opens up in your favorite browser, you will need one more step to install the Project Templates. Start Visual Studio 2012. Create a new MvvmLight (Win8) app. Run the application. You will see a string showing “Welcome to MVVM Light”. In the Solution explorer, right click on MainPage.xaml and select Open in Blend. Now you should see “Welcome to MVVM Light [Design]” What happens here is that Expression Blend runs different code at design time than the application runs at runtime. To do this, we use design-time detection (as explained in a previous article) and use that information to initialize a different data service at design time. To understand this better, open the ViewModelLocator.cs file in the ViewModel folder and see how the DesignDataService is used at design time, while the DataService is used at runtime. In a real-life applicationm, DataService would be used to connect to a web service, for instance. When design time data fails Sometimes however, the creation of design time data fails. It can be very difficult to understand exactly what is happening. Expression Blend is not giving a lot of information about what happened. Thankfully, we can use a trick: Attaching a debugger to Expression Blend and debug the design time code. In WPF and Silverlight (including Windows Phone 7), you could simply attach the debugger to Blend.exe (using the “Managed (v4.5, v4.0) code” option even for Silverlight!!) In Windows 8 however, things are just a bit different. This is because the designer that renders the actual representation of the Windows 8 app runs in its own process. Let’s illustrate that: Open the file DesignDataService in the Design folder. Modify the GetData method to look like this: public void GetData(Action<DataItem, Exception> callback) { throw new Exception(); // Use this to create design time data var item = new DataItem("Welcome to MVVM Light [design]"); callback(item, null); } Go to Blend and build the application. The build succeeds, but now the page is empty. The creation of the design time data failed, but we don’t get a warning message. We need to investigate what’s wrong. Close MainPage.xaml Go to Visual Studio and select the menu Debug, Attach to Process. Update: Make sure that you select “Managed (v4.5, v4.0) code” in the “Attach to” field. Find the process named XDesProc.exe. You should have at least two, one for the Visual Studio 2012 designer surface, and one for Expression Blend. Unfortunately in this screen it is not obvious which is which. Let’s find out in the Task Manager. Press Ctrl-Alt-Del and select Task Manager Go to the Details tab and sort the processes by name. Find the one that says “Blend for Microsoft Visual Studio 2012 XAML UI Designer” and write down the process ID. Go back to the Attach to Process dialog in Visual Studio. sort the processes by ID and attach the debugger to the correct instance of XDesProc.exe. Open the MainViewModel (in the ViewModel folder) Place a breakpoint on the first line of the MainViewModel constructor. Go to Blend and open the MainPage.xaml again. At this point, the debugger breaks in Visual Studio and you can execute your code step by step. Simply step inside the dataservice call, and find the exception that you had placed there. Visual Studio gives you additional information which helps you to solve the issue. More info and Conclusion I want to thank the amazing people on the Expression Blend team for being very fast in guiding me in that matter and encouraging me to blog about it. More information about the XDesProc.exe process can be found here. I had to work on a Windows 8 app for a few days without design time data because of an Exception thrown somewhere in the code, and it was really painful. With the debugger, finding the issue was a simple matter of stepping into the code until it threw the exception.   Laurent Bugnion (GalaSoft) Subscribe | Twitter | Facebook | Flickr | LinkedIn

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