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  • Wireless doesn't work on a Broadcom BCM4312

    - by Boderick
    As stated, I've just upgraded to 12.04 and my Dell Inspiron 1545 isn't recognising its wireless card and I was wondering if anybody could help? Edit: Okay, so I found the wireless card by using lspci -vvv and it returned this: 0c:00.0 Network controller: Broadcom Corporation BCM4312 802.11b/g LP-PHY (rev 01) Subsystem: Dell Wireless 1397 WLAN Mini-Card Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast TAbort- SERR- Kernel modules: ssb lsmod Module Size Used by dm_crypt 22528 0 joydev 17393 0 dell_wmi 12601 0 sparse_keymap 13658 1 dell_wmi dell_laptop 13671 0 dcdbas 14098 1 dell_laptop psmouse 72919 0 uvcvideo 67203 0 serio_raw 13027 0 videodev 86588 1 uvcvideo snd_hda_codec_idt 60251 1 mac_hid 13077 0 snd_hda_intel 32765 5 snd_hda_codec 109562 2 snd_hda_codec_idt,snd_hda_intel snd_hwdep 13276 1 snd_hda_codec parport_pc 32114 0 rfcomm 38139 0 bnep 17830 2 ppdev 12849 0 snd_pcm 80845 3 snd_hda_intel,snd_hda_codec bluetooth 158438 10 rfcomm,bnep snd_seq_midi 13132 0 snd_rawmidi 25424 1 snd_seq_midi snd_seq_midi_event 14475 1 snd_seq_midi snd_seq 51567 2 snd_seq_midi,snd_seq_midi_event snd_timer 28931 2 snd_pcm,snd_seq snd_seq_device 14172 3 snd_seq_midi,snd_rawmidi,snd_seq binfmt_misc 17292 1 snd 62064 18 snd_hda_codec_idt,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,snd_rawmidi,snd_seq,snd_timer,snd_seq_device soundcore 14635 1 snd snd_page_alloc 14108 2 snd_hda_intel,snd_pcm lp 17455 0 parport 40930 3 parport_pc,ppdev,lp sky2 53628 0 ums_realtek 17920 0 uas 17699 0 i915 414603 3 wmi 18744 1 dell_wmi drm_kms_helper 45466 1 i915 drm 197692 4 i915,drm_kms_helper i2c_algo_bit 13199 1 i915 video 19068 1 i915 usb_storage 39646 1 ums_realtek ifconfig -a eth0 Link encap:Ethernet HWaddr 00:23:ae:24:71:45 inet addr:192.168.1.158 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::223:aeff:fe24:7145/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:14340 errors:0 dropped:0 overruns:0 frame:0 TX packets:10191 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:15403754 (15.4 MB) TX bytes:1262570 (1.2 MB) Interrupt:18 ham0 Link encap:Ethernet HWaddr 7a:79:05:2d:b0:f7 inet addr:5.45.176.247 Bcast:5.255.255.255 Mask:255.0.0.0 inet6 addr: fe80::7879:5ff:fe2d:b0f7/64 Scope:Link inet6 addr: 2620:9b::52d:b0f7/96 Scope:Global UP BROADCAST RUNNING MULTICAST MTU:1404 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:179 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:500 RX bytes:0 (0.0 B) TX bytes:27480 (27.4 KB) 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:433 errors:0 dropped:0 overruns:0 frame:0 TX packets:433 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:60051 (60.0 KB) TX bytes:60051 (60.0 KB) iwconfig lo no wireless extensions. ham0 no wireless extensions. eth0 no wireless extensions. the results for sudo lshw -class network *-network description: Wireless interface product: BCM4312 802.11b/g LP-PHY vendor: Broadcom Corporation physical id: 0 bus info: pci@0000:0c:00.0 logical name: eth1 version: 01 serial: 00:22:5f:77:1f:e6 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=wl0 driverversion=5.100.82.38 latency=0 multicast=yes wireless=IEEE 802.11bg resources: irq:17 memory:f69fc000-f69fffff *-network description: Ethernet interface product: 88E8040 PCI-E Fast Ethernet Controller vendor: Marvell Technology Group Ltd. physical id: 0 bus info: pci@0000:09:00.0 logical name: eth0 version: 13 serial: 00:23:ae:24:71:45 size: 100Mbit/s capacity: 100Mbit/s width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=sky2 driverversion=1.30 duplex=full firmware=N/A ip=192.168.1.158 latency=0 link=yes multicast=yes port=twisted pair speed=100Mbit/s resources: irq:45 memory:f68fc000-f68fffff ioport:de00(size=256) *-network description: Ethernet interface physical id: 2 logical name: ham0 serial: 7a:79:05:2d:b0:f7 size: 10Mbit/s capabilities: ethernet physical configuration: autonegotiation=off broadcast=yes driver=tun driverversion=1.6 duplex=full firmware=N/A ip=5.45.176.247 link=yes multicast=yes port=twisted pair speed=10Mbit/s and the results of rfkill list all 0: brcmwl-0: Wireless LAN Soft blocked: yes Hard blocked: yes 1: dell-wifi: Wireless LAN Soft blocked: yes Hard blocked: yes

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  • Fresh Ubuntu Install - Grub not loading

    - by Ryan Sharp
    System Ubuntu 12.04 64-bit Windows 7 SP1 Samsung 64GB SSD - OS' Samsung 1TB HDD - Games, /Home, Swap WD 300'ishGB HDD - Backup Okay, so I'm very frustrated, so please excuse me if I miss anything out as my head is clouded by anger and impatience, etc. I'll try me best, though. First of all, I'll explain how I got to my predicament. I finally got my new SSD. I firstly installed Windows, which completed without a hitch. Afterwards, I tried to install Ubuntu, which failed several times due to problems irrelevant to this question, but I mention this to explain my frustrations, sorry. Anyway, I finally installed Ubuntu. However, I chose the 'bootloader' to be installed on the same partition as where I was installing the Ubuntu Root partition, as that was what I believed to be the best choice. It was of my thinking that it was supposed to go on the same partition and on the SSD, which is my OS drive, though with my problem, it apparently was wrong. So I tried to fix it by checking guides and following their directions, but seemed to have messed it up even more. Here is what I receive after I use the fdisk -l command: (I also added explanations for which I used each partition for) Disk /dev/sda: 64.0 GB, 64023257088 bytes 255 heads, 63 sectors/track, 7783 cylinders, total 125045424 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x324971d1 Device Boot Start End Blocks Id System /dev/sda1 * 2048 206847 102400 7 HPFS/NTFS/exFAT /dev/sda2 208896 48957439 24374272 7 HPFS/NTFS/exFAT /dev/sda3 48959486 125044735 38042625 5 Extended /dev/sda5 48959488 125044735 38042624 83 Linux sda1 --/ Windows Recovery sda2 --/ Windows 7 sda3/5 --/ Ubuntu root [ / ] Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes 255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xc0ee6a69 Device Boot Start End Blocks Id System /dev/sdb1 1024208894 1953523711 464657409 5 Extended /dev/sdb3 * 2048 1024206847 512102400 7 HPFS/NTFS/exFAT /dev/sdb5 1024208896 1939851263 457821184 83 Linux /dev/sdb6 1939853312 1953523711 6835200 82 Linux swap / Solaris sdb3 --/ Partition for Steam games, etc. sdb5 --/ Ubuntu Home [ /home ] sdb6 --/ Ubuntu Swap Partition table entries are not in disk order Disk /dev/sdc: 320.1 GB, 320072933376 bytes 255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x292eee23 Device Boot Start End Blocks Id System /dev/sdc1 2048 625141759 312569856 7 HPFS/NTFS/exFAT sdc1 --/ Generic backup I also used a Boot Script that other users suggested, so that I can give more details on my partitions and also where Grub is located... ============================= Boot Info Summary: =============================== => Grub2 (v1.99) is installed in the MBR of /dev/sda and looks at sector 1 of the same hard drive for core.img. core.img is at this location and looks for (,msdos5)/boot/grub on this drive. => Grub2 (v1.99) is installed in the MBR of /dev/sdb and looks at sector 1 of the same hard drive for core.img. core.img is at this location and looks for (,msdos5)/boot/grub on this drive. => Windows is installed in the MBR of /dev/sdc. Now that is weird... Why would Grub2 be installed on both my SSD and HDD? Even weirder is why is Windows on the MBR of my backup hard drive? Nothing I did should have done that... Anyway, here is the entire Output from that script... PASTEBIN So, to summarize what I need: How can I fix my setup so grub loads on startup? How can I clean my partitions to remove unnecessary grubs? What did I do wrong so that I don't do something so daft again? Thank you so much for reading, and I hope you can help me. I've been trying to have a successful setup since Friday, and I'm almost at the point that I'm really tempted to throw my computer out the window due to my frustration.

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  • WiFi stops working after a while in Lenovo ThinkPad W520 (Ubuntu 12.04)

    - by el10780
    After several minutes(I do not know how many) there is no internet connection on my laptop via Wi-Fi.Ubuntu doesn't show any kind of message that my WiFi was disconnected neither there is a signal drop,but suddenly Firefox stops connecting to web pages.I checked my modem/router and it seems that it is working fine.I tried also to reboot the WiFi device and nothing happens.The only thing that it makes it work again is a reboot of the system and if I do not want to do a reboot then I am enforced to connect to the Internet using Ethernet cable.Does anybody know what is happening? ## Some Hardware info that might be helpful ## el10780@ThinkPad-W520:~$ sudo lshw -class network *-network description: Ethernet interface product: 82579LM Gigabit Network Connection vendor: Intel Corporation physical id: 19 bus info: pci@0000:00:19.0 logical name: eth0 version: 04 serial: f0:de:f1:f1:be:10 size: 100Mbit/s capacity: 1Gbit/s width: 32 bits clock: 33MHz capabilities: pm msi bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=e1000e driverversion=1.5.1-k duplex=full firmware=0.13-3 ip=192.168.0.10 latency=0 link=yes multicast=yes port=twisted pair speed=100Mbit/s resources: irq:50 memory:f3a00000-f3a1ffff memory:f3a2b000-f3a2bfff ioport:6080(size=32) *-network description: Wireless interface product: Centrino Advanced-N + WiMAX 6250 vendor: Intel Corporation physical id: 0 bus info: pci@0000:03:00.0 logical name: wlan0 version: 5e serial: 64:80:99:63:14:74 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=iwlwifi driverversion=3.2.0-26-generic firmware=41.28.5.1 build 33926 ip=192.168.0.6 latency=0 link=yes multicast=yes wireless=IEEE 802.11abgn resources: irq:52 memory:f3900000-f3901fff *-network description: Ethernet interface physical id: 1 bus info: usb@2:1.3 logical name: wmx0 serial: 00:1d:e1:53:b2:e8 capabilities: ethernet physical configuration: driver=i2400m firmware=i6050-fw-usb-1.5.sbcf link=no el10780@ThinkPad-W520:~$ lspci 00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09) 00:01.0 PCI bridge: Intel Corporation Xeon E3-1200/2nd Generation Core Processor Family PCI Express Root Port (rev 09) 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) 00:16.0 Communication controller: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 (rev 04) 00:16.3 Serial controller: Intel Corporation 6 Series/C200 Series Chipset Family KT Controller (rev 04) 00:19.0 Ethernet controller: Intel Corporation 82579LM Gigabit Network Connection (rev 04) 00:1a.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 (rev 04) 00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 04) 00:1c.0 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 (rev b4) 00:1c.1 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 2 (rev b4) 00:1c.3 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 4 (rev b4) 00:1c.4 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 5 (rev b4) 00:1c.6 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 7 (rev b4) 00:1d.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 (rev 04) 00:1f.0 ISA bridge: Intel Corporation QM67 Express Chipset Family LPC Controller (rev 04) 00:1f.2 SATA controller: Intel Corporation 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller (rev 04) 00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 04) 01:00.0 VGA compatible controller: NVIDIA Corporation GF108 [Quadro 1000M] (rev a1) 03:00.0 Network controller: Intel Corporation Centrino Advanced-N + WiMAX 6250 (rev 5e) 0d:00.0 System peripheral: Ricoh Co Ltd Device e823 (rev 08) 0d:00.3 FireWire (IEEE 1394): Ricoh Co Ltd R5C832 PCIe IEEE 1394 Controller (rev 04) 0e:00.0 USB controller: NEC Corporation uPD720200 USB 3.0 Host Controller (rev 04) el10780@ThinkPad-W520:~$ rfkill list all 0: hci0: Bluetooth Soft blocked: no Hard blocked: no 1: tpacpi_bluetooth_sw: Bluetooth Soft blocked: no Hard blocked: no 2: phy0: Wireless LAN Soft blocked: no Hard blocked: no 3: i2400m-usb:2-1.3:1.0: WiMAX Soft blocked: yes Hard blocked: no The weirdest thing is this screenshot which I took after running the **Additional Drivers** program.I mean I have a NVidia Quadro 1000M and my Intel Centrino WiFi Card and this shows that there are not proprietay drivers for my system. http://imageshack.us/photo/my-images/268/screenshotfrom201207062.png/

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  • Need help partitioning when reinstalling Ubuntu 14.04

    - by Chris M.
    I upgraded to 14.04 about a month ago on my HP Mini netbook (about 16 GB hard disk). A few days ago the system crashed (I don't know why but I was using internet at the time). When I restarted the computer, Ubuntu would not load. Instead, I got a message from the BIOS saying Reboot and Select proper Boot device or Insert Boot Media in selected Boot device and press a key I took this to mean that I needed to reinstall 14.04. When I try to reinstall Ubuntu from the USB stick, I choose "Erase disk and install Ubuntu" but then I get a message: Some of the partitions you created are too small. Please make the following partitions at least this large: / 3.3 GB If you do not go back to the partitioner and increase the size of these partitions, the installation may fail. At first I hit Continue to see if it would install anyway, and it gave the message: The attempt to mount a file system with type ext4 in SCSI1 (0,0,0), partition # 1 (sda) at / failed. You may resume partitioning from the partitioning menu. The second time I hit Go Back, and it took me to the following partitioning table: Device Type Mount Point Format Size Used System /dev/sda /dev/sda1 ext4 (checked) 3228 MB Unknown /dev/sda5 swap (not checked) 1063 MB Unknown + - Change New Partition Table... Revert Device for boot loader installation: /dev/sda ATA JM Loader 001 (4.3 GB) At this point I'm not sure what to do. I've never partitioned my hard drive before and I don't want to screw things up. (I'm not particularly tech savvy.) Can you instruct me what I should do. (P.S. I'm afraid the table might not appear as I typed it in.) Results from fdisk: ubuntu@ubuntu:~$ sudo fdisk -l Disk /dev/sda: 4294 MB, 4294967296 bytes 255 heads, 63 sectors/track, 522 cylinders, total 8388608 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/sda doesn't contain a valid partition table Disk /dev/sdb: 7860 MB, 7860125696 bytes 155 heads, 31 sectors/track, 3194 cylinders, total 15351808 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x0009a565 Device Boot Start End Blocks Id System /dev/sdb1 * 2768 15351807 7674520 b W95 FAT32 ubuntu@ubuntu:~$ Here is what it displays when I open the Disks utility (I tried the screenshot terminal command you suggested but it didn't seem to do anything): 4.3 GB Hard Disk /dev/sda Model: JM Loader 001 (01000001) Size: 4.3 GB (4,294,967,296 bytes) Serial Number: 01234123412341234 Assessment: SMART is not supported Volumes Size: 4.3 GB (4,294,967,296 bytes) Device: /dev/sda Contents: Unknown (There is a button in the utility that when you click it gives the following options: Format... Create Disk Image... Restore Disk Image... Benchmark but SMART Data & Self-Tests... is dimmed out) When I hit F9 Change Boot Device Order, it shows the hard drive as: SATA:PM-JM Loader 001 When I hit F10 to get me into the BIOS Setup Utility, under Diagnostic it shows: Primary Hard Disk Self Test Not Support NetworkManager Tool State: disconnected Device: eth0 Type: Wired Driver: atl1c State: unavailable Default: no HW Address: 00:26:55:B0:7F:0C Capabilities: Carrier Detect: yes Wired Properties Carrier: off When I run command lshw -C network, I get: WARNING: you should run this program as super-user. *-network description: Network controller product: BCM4312 802.11b/g LP-PHY vendor: Broadcom Corporation physical id: 0 bus info: pci@0000:01:00.0 version: 01 width: 64 bits clock: 33MHz capabilities: bus_master cap_list configuration: driver=b43-pci-bridge latency=0 resources: irq:16 memory:feafc000-feafffff *-network description: Ethernet interface product: AR8132 Fast Ethernet vendor: Qualcomm Atheros physical id: 0 bus info: pci@0000:02:00.0 logical name: eth0 version: c0 serial: 00:26:55:b0:7f:0c capacity: 100Mbit/s width: 64 bits clock: 33MHz capabilities: bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=atl1c driverversion=1.0.1.1-NAPI latency=0 link=no multicast=yes port=twisted pair resources: irq:43 memory:febc0000-febfffff ioport:ec80(size=128) WARNING: output may be incomplete or inaccurate, you should run this program as super-user.

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  • Columnstore Case Study #1: MSIT SONAR Aggregations

    - by aspiringgeek
    Preamble This is the first in a series of posts documenting big wins encountered using columnstore indexes in SQL Server 2012 & 2014.  Many of these can be found in this deck along with details such as internals, best practices, caveats, etc.  The purpose of sharing the case studies in this context is to provide an easy-to-consume quick-reference alternative. Why Columnstore? If we’re looking for a subset of columns from one or a few rows, given the right indexes, SQL Server can do a superlative job of providing an answer. If we’re asking a question which by design needs to hit lots of rows—DW, reporting, aggregations, grouping, scans, etc., SQL Server has never had a good mechanism—until columnstore. Columnstore indexes were introduced in SQL Server 2012. However, they're still largely unknown. Some adoption blockers existed; yet columnstore was nonetheless a game changer for many apps.  In SQL Server 2014, potential blockers have been largely removed & they're going to profoundly change the way we interact with our data.  The purpose of this series is to share the performance benefits of columnstore & documenting columnstore is a compelling reason to upgrade to SQL Server 2014. App: MSIT SONAR Aggregations At MSIT, performance & configuration data is captured by SCOM. We archive much of the data in a partitioned data warehouse table in SQL Server 2012 for reporting via an application called SONAR.  By definition, this is a primary use case for columnstore—report queries requiring aggregation over large numbers of rows.  New data is refreshed each night by an automated table partitioning mechanism—a best practices scenario for columnstore. The Win Compared to performance using classic indexing which resulted in the expected query plan selection including partition elimination vs. SQL Server 2012 nonclustered columnstore, query performance increased significantly.  Logical reads were reduced by over a factor of 50; both CPU & duration improved by factors of 20 or more.  Other than creating the columnstore index, no special modifications or tweaks to the app or databases schema were necessary to achieve the performance improvements.  Existing nonclustered indexes were rendered superfluous & were deleted, thus mitigating maintenance challenges such as defragging as well as conserving disk capacity. Details The table provides the raw data & summarizes the performance deltas. Logical Reads (8K pages) CPU (ms) Durn (ms) Columnstore 160,323 20,360 9,786 Conventional Table & Indexes 9,053,423 549,608 193,903 ? x56 x27 x20 The charts provide additional perspective of this data.  "Conventional vs. Columnstore Metrics" document the raw data.  Note on this linear display the magnitude of the conventional index performance vs. columnstore.  The “Metrics (?)” chart expresses these values as a ratio. Summary For DW, reports, & other BI workloads, columnstore often provides significant performance enhancements relative to conventional indexing.  I have documented here, the first in a series of reports on columnstore implementations, results from an initial implementation at MSIT in which logical reads were reduced by over a factor of 50; both CPU & duration improved by factors of 20 or more.  Subsequent features in this series document performance enhancements that are even more significant. 

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  • My LAN USB NIC is not working in ubuntu 11.10?

    - by Gaurav_Java
    Today i start my system its seems that my LAN port is not working . so i buy one USB to LAN adapter and i plug in ubuntu system its doen't connect automatically .when i check result lsusb its shows me that there is one DM9601 Ethernet adapter is connected when i click on network information in panel its shows me that there is something " wired NEtwork (Broadcom NetLink BCM5784M gigabit Ethernet PCIe) I think want some driver for that .i don't have any idea how it can be used ? here output of sudo lspci -nn *00:00.0 Host bridge [0600]: Intel Corporation Mobile 4 Series Chipset Memory Controller Hub [8086:2a40] (rev 07) 00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07) 00:02.1 Display controller [0380]: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a43] (rev 07) 00:1a.0 USB Controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #4 [8086:2937] (rev 03) 00:1a.1 USB Controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #5 [8086:2938] (rev 03) 00:1a.7 USB Controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #2 [8086:293c] (rev 03) 00:1b.0 Audio device [0403]: Intel Corporation 82801I (ICH9 Family) HD Audio Controller [8086:293e] (rev 03) 00:1c.0 PCI bridge [0604]: Intel Corporation 82801I (ICH9 Family) PCI Express Port 1 [8086:2940] (rev 03) 00:1c.1 PCI bridge [0604]: Intel Corporation 82801I (ICH9 Family) PCI Express Port 2 [8086:2942] (rev 03) 00:1c.2 PCI bridge [0604]: Intel Corporation 82801I (ICH9 Family) PCI Express Port 3 [8086:2944] (rev 03) 00:1c.4 PCI bridge [0604]: Intel Corporation 82801I (ICH9 Family) PCI Express Port 5 [8086:2948] (rev 03) 00:1d.0 USB Controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #1 [8086:2934] (rev 03) 00:1d.1 USB Controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #2 [8086:2935] (rev 03) 00:1d.2 USB Controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #3 [8086:2936] (rev 03) 00:1d.3 USB Controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #6 [8086:2939] (rev 03) 00:1d.7 USB Controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #1 [8086:293a] (rev 03) 00:1e.0 PCI bridge [0604]: Intel Corporation 82801 Mobile PCI Bridge [8086:2448] (rev 93) 00:1f.0 ISA bridge [0601]: Intel Corporation ICH9M LPC Interface Controller [8086:2919] (rev 03) 00:1f.2 SATA controller [0106]: Intel Corporation ICH9M/M-E SATA AHCI Controller [8086:2929] (rev 03) 00:1f.3 SMBus [0c05]: Intel Corporation 82801I (ICH9 Family) SMBus Controller [8086:2930] (rev 03) 02:00.0 Ethernet controller [0200]: Broadcom Corporation NetLink BCM5784M Gigabit Ethernet PCIe [14e4:1698] (rev 10) 04:00.0 Network controller [0280]: Intel Corporation WiFi Link 5100 [8086:4232]* sudo lshw -class network *-network description: Ethernet interface product: NetLink BCM5784M Gigabit Ethernet PCIe vendor: Broadcom Corporation physical id: 0 bus info: pci@0000:02:00.0 logical name: eth0 version: 10 serial: 00:1f:16:9a:56:98 capacity: 1Gbit/s width: 64 bits clock: 33MHz capabilities: pm vpd msi pciexpress bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=tg3 driverversion=3.119 firmware=sb v2.19 latency=0 link=no multicast=yes port=twisted pair resources: irq:47 memory:f4500000-f450ffff *-network DISABLED description: Wireless interface product: WiFi Link 5100 vendor: Intel Corporation physical id: 0 bus info: pci@0000:04:00.0 logical name: wlan0 version: 00 serial: 00:22:fa:09:02:00 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=iwlagn driverversion=3.0.0-17-generic firmware=8.83.5.1 build 33692 latency=0 link=no multicast=yes wireless=IEEE 802.11abgn resources: irq:46 memory:f4600000-f4601fff *-network description: Ethernet interface physical id: 4 logical name: eth1 serial: 00:60:6e:00:f1:7d size: 100Mbit/s capacity: 100Mbit/s capabilities: ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=dm9601 driverversion=22-Aug-2005 duplex=full firmware=Davicom DM9601 USB Ethernet ip=192.168.1.34 link=yes multicast=yes port=MII speed=100Mbit/s I am using Wimax internet connection which i have to connect from browser . at that time my system is not showing that i am connected to any wired connection. but when i connect internet from other system after getting conneted to internet . when i plug again my USB LAN then its shows that you are conneted to wired connetion. here is screenshot for conneting wimax from browser after connecting to internet network connection shows

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  • help in the Donalds B. Johnson's algorithm, i cannot understand the pseudo code

    - by Pitelk
    Hi , does anyone know the Donald B. Johnson's algorithm which enumarates all the elementary circuits (cycles) in a Directed graph? link text I have the paper he had published in 1975 but I cannot understand the pseudo-code. My goal is to implement this algorithm in java. Some questions i have is for example what is the matrix Ak it refers to. In the pseudo code mentions that Ak:=adjacency structure of strong component K with least vertex in subgraph of G induced by {s,s+1,....n}; Does that mean i have to implement another algorithm that finds the Ak matrix? Another question is what the following means? begin logical f; Does also the line "logical procedure CIRCUIT (integer value v);" means that the circuit procedure returns a logical variable. In the pseudo code also has the line "CIRCUIT := f;" . Does this mean? It would be great if someone could translate this 1970's pseudocode to a more modern type of pseudo code so i can understand it in case you are interested to help but you cannot find the paper please email me at [email protected] and i will send you the paper. Thanks in advance

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  • slicing a 2d numpy array

    - by MedicalMath
    The following code: import numpy as p myarr=[[0,1],[0,6],[0,1],[0,6],[0,1],[0,6],[0,1],[0,6],[0,1],[0,6],[0,1],[0,6],[0,1],[0,6],[0,1],[0,6],[0,1],[0,6]] copy=p.array(myarr) p.mean(copy)[:,1] Is generating the following error message: Traceback (most recent call last): File "<pyshell#3>", line 1, in <module> p.mean(copy)[:,1] IndexError: 0-d arrays can only use a single () or a list of newaxes (and a single ...) as an index I looked up the syntax at this link and I seem to be using the correct syntax to slice. However, when I type copy[:,1] into the Python shell, it gives me the following output, which is clearly wrong, and is probably what is throwing the error: array([1, 6, 1, 6, 1, 6, 1, 6, 1, 6, 1, 6, 1, 6, 1, 6, 1, 6]) Can anyone show me how to fix my code so that I can extract the second column and then take the mean of the second column as intended in the original code above? EDIT: Thank you for your solutions. However, my posting was an oversimplification of my real problem. I used your solutions in my real code, and got a new error. Here is my real code with one of your solutions that I tried: filteredSignalArray=p.array(filteredSignalArray) logical=p.logical_and(EndTime-10.0<=matchingTimeArray,matchingTimeArray<=EndTime) finalStageTime=matchingTimeArray.compress(logical) finalStageFiltered=filteredSignalArray.compress(logical) for j in range(len(finalStageTime)): if j == 0: outputArray=[[finalStageTime[j],finalStageFiltered[j]]] else: outputArray+=[[finalStageTime[j],finalStageFiltered[j]]] print 'outputArray[:,1].mean() is: ',outputArray[:,1].mean() And here is the error message that is now being generated by the new code: File "mypath\myscript.py", line 1545, in WriteToOutput10SecondsBeforeTimeMarker print 'outputArray[:,1].mean() is: ',outputArray[:,1].mean() TypeError: list indices must be integers, not tuple Second EDIT: This is solved now that I added: outputArray=p.array(outputArray) above my code. I have been at this too many hours and need to take a break for a while if I am making these kinds of mistakes.

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  • iOS layout; I'm not getting it

    - by Tbee
    Well, "not getting it" is too harsh; I've got it working in for what for me is a logical setup, but it does not seem to be what iOS deems logical. So I'm not getting something. Suppose I've got an app that shows two pieces of information; a date and a table. According to the MVC approach I've got three MVC at work here, one for the date, one for the table and one that takes both these MCVs and makes it into a screen, wiring them up. The master MVC knows how/where it wants to layout the two sub MVC's. Each detail MVC only takes care of its own childeren within the bounds that were specified by the master MVC. Something like: - (void)loadView { MVC* mvc1 = [[MVC1 alloc] initwithFrame:...] [self.view addSubview:mvc1.view]; MVC* mvc2 = [[MVC2 alloc] initwithFrame:...] [self.view addSubview:mvc2.view]; } If the above is logical (which is it for me) then I would expect any MVC class to have a constructor "initWithFrame". But an MVC does not, only view have this. Why? How would one correctly layout nested MVCs? (Naturally I do not have just these two, but the detail MVCs have sub MVCs again.)

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  • Improving Partitioned Table Join Performance

    - by Paul White
    The query optimizer does not always choose an optimal strategy when joining partitioned tables. This post looks at an example, showing how a manual rewrite of the query can almost double performance, while reducing the memory grant to almost nothing. Test Data The two tables in this example use a common partitioning partition scheme. The partition function uses 41 equal-size partitions: CREATE PARTITION FUNCTION PFT (integer) AS RANGE RIGHT FOR VALUES ( 125000, 250000, 375000, 500000, 625000, 750000, 875000, 1000000, 1125000, 1250000, 1375000, 1500000, 1625000, 1750000, 1875000, 2000000, 2125000, 2250000, 2375000, 2500000, 2625000, 2750000, 2875000, 3000000, 3125000, 3250000, 3375000, 3500000, 3625000, 3750000, 3875000, 4000000, 4125000, 4250000, 4375000, 4500000, 4625000, 4750000, 4875000, 5000000 ); GO CREATE PARTITION SCHEME PST AS PARTITION PFT ALL TO ([PRIMARY]); There two tables are: CREATE TABLE dbo.T1 ( TID integer NOT NULL IDENTITY(0,1), Column1 integer NOT NULL, Padding binary(100) NOT NULL DEFAULT 0x,   CONSTRAINT PK_T1 PRIMARY KEY CLUSTERED (TID) ON PST (TID) );   CREATE TABLE dbo.T2 ( TID integer NOT NULL, Column1 integer NOT NULL, Padding binary(100) NOT NULL DEFAULT 0x,   CONSTRAINT PK_T2 PRIMARY KEY CLUSTERED (TID, Column1) ON PST (TID) ); The next script loads 5 million rows into T1 with a pseudo-random value between 1 and 5 for Column1. The table is partitioned on the IDENTITY column TID: INSERT dbo.T1 WITH (TABLOCKX) (Column1) SELECT (ABS(CHECKSUM(NEWID())) % 5) + 1 FROM dbo.Numbers AS N WHERE n BETWEEN 1 AND 5000000; In case you don’t already have an auxiliary table of numbers lying around, here’s a script to create one with 10 million rows: CREATE TABLE dbo.Numbers (n bigint PRIMARY KEY);   WITH L0 AS(SELECT 1 AS c UNION ALL SELECT 1), L1 AS(SELECT 1 AS c FROM L0 AS A CROSS JOIN L0 AS B), L2 AS(SELECT 1 AS c FROM L1 AS A CROSS JOIN L1 AS B), L3 AS(SELECT 1 AS c FROM L2 AS A CROSS JOIN L2 AS B), L4 AS(SELECT 1 AS c FROM L3 AS A CROSS JOIN L3 AS B), L5 AS(SELECT 1 AS c FROM L4 AS A CROSS JOIN L4 AS B), Nums AS(SELECT ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) AS n FROM L5) INSERT dbo.Numbers WITH (TABLOCKX) SELECT TOP (10000000) n FROM Nums ORDER BY n OPTION (MAXDOP 1); Table T1 contains data like this: Next we load data into table T2. The relationship between the two tables is that table 2 contains ‘n’ rows for each row in table 1, where ‘n’ is determined by the value in Column1 of table T1. There is nothing particularly special about the data or distribution, by the way. INSERT dbo.T2 WITH (TABLOCKX) (TID, Column1) SELECT T.TID, N.n FROM dbo.T1 AS T JOIN dbo.Numbers AS N ON N.n >= 1 AND N.n <= T.Column1; Table T2 ends up containing about 15 million rows: The primary key for table T2 is a combination of TID and Column1. The data is partitioned according to the value in column TID alone. Partition Distribution The following query shows the number of rows in each partition of table T1: SELECT PartitionID = CA1.P, NumRows = COUNT_BIG(*) FROM dbo.T1 AS T CROSS APPLY (VALUES ($PARTITION.PFT(TID))) AS CA1 (P) GROUP BY CA1.P ORDER BY CA1.P; There are 40 partitions containing 125,000 rows (40 * 125k = 5m rows). The rightmost partition remains empty. The next query shows the distribution for table 2: SELECT PartitionID = CA1.P, NumRows = COUNT_BIG(*) FROM dbo.T2 AS T CROSS APPLY (VALUES ($PARTITION.PFT(TID))) AS CA1 (P) GROUP BY CA1.P ORDER BY CA1.P; There are roughly 375,000 rows in each partition (the rightmost partition is also empty): Ok, that’s the test data done. Test Query and Execution Plan The task is to count the rows resulting from joining tables 1 and 2 on the TID column: SET STATISTICS IO ON; DECLARE @s datetime2 = SYSUTCDATETIME();   SELECT COUNT_BIG(*) FROM dbo.T1 AS T1 JOIN dbo.T2 AS T2 ON T2.TID = T1.TID;   SELECT DATEDIFF(Millisecond, @s, SYSUTCDATETIME()); SET STATISTICS IO OFF; The optimizer chooses a plan using parallel hash join, and partial aggregation: The Plan Explorer plan tree view shows accurate cardinality estimates and an even distribution of rows across threads (click to enlarge the image): With a warm data cache, the STATISTICS IO output shows that no physical I/O was needed, and all 41 partitions were touched: Running the query without actual execution plan or STATISTICS IO information for maximum performance, the query returns in around 2600ms. Execution Plan Analysis The first step toward improving on the execution plan produced by the query optimizer is to understand how it works, at least in outline. The two parallel Clustered Index Scans use multiple threads to read rows from tables T1 and T2. Parallel scan uses a demand-based scheme where threads are given page(s) to scan from the table as needed. This arrangement has certain important advantages, but does result in an unpredictable distribution of rows amongst threads. The point is that multiple threads cooperate to scan the whole table, but it is impossible to predict which rows end up on which threads. For correct results from the parallel hash join, the execution plan has to ensure that rows from T1 and T2 that might join are processed on the same thread. For example, if a row from T1 with join key value ‘1234’ is placed in thread 5’s hash table, the execution plan must guarantee that any rows from T2 that also have join key value ‘1234’ probe thread 5’s hash table for matches. The way this guarantee is enforced in this parallel hash join plan is by repartitioning rows to threads after each parallel scan. The two repartitioning exchanges route rows to threads using a hash function over the hash join keys. The two repartitioning exchanges use the same hash function so rows from T1 and T2 with the same join key must end up on the same hash join thread. Expensive Exchanges This business of repartitioning rows between threads can be very expensive, especially if a large number of rows is involved. The execution plan selected by the optimizer moves 5 million rows through one repartitioning exchange and around 15 million across the other. As a first step toward removing these exchanges, consider the execution plan selected by the optimizer if we join just one partition from each table, disallowing parallelism: SELECT COUNT_BIG(*) FROM dbo.T1 AS T1 JOIN dbo.T2 AS T2 ON T2.TID = T1.TID WHERE $PARTITION.PFT(T1.TID) = 1 AND $PARTITION.PFT(T2.TID) = 1 OPTION (MAXDOP 1); The optimizer has chosen a (one-to-many) merge join instead of a hash join. The single-partition query completes in around 100ms. If everything scaled linearly, we would expect that extending this strategy to all 40 populated partitions would result in an execution time around 4000ms. Using parallelism could reduce that further, perhaps to be competitive with the parallel hash join chosen by the optimizer. This raises a question. If the most efficient way to join one partition from each of the tables is to use a merge join, why does the optimizer not choose a merge join for the full query? Forcing a Merge Join Let’s force the optimizer to use a merge join on the test query using a hint: SELECT COUNT_BIG(*) FROM dbo.T1 AS T1 JOIN dbo.T2 AS T2 ON T2.TID = T1.TID OPTION (MERGE JOIN); This is the execution plan selected by the optimizer: This plan results in the same number of logical reads reported previously, but instead of 2600ms the query takes 5000ms. The natural explanation for this drop in performance is that the merge join plan is only using a single thread, whereas the parallel hash join plan could use multiple threads. Parallel Merge Join We can get a parallel merge join plan using the same query hint as before, and adding trace flag 8649: SELECT COUNT_BIG(*) FROM dbo.T1 AS T1 JOIN dbo.T2 AS T2 ON T2.TID = T1.TID OPTION (MERGE JOIN, QUERYTRACEON 8649); The execution plan is: This looks promising. It uses a similar strategy to distribute work across threads as seen for the parallel hash join. In practice though, performance is disappointing. On a typical run, the parallel merge plan runs for around 8400ms; slower than the single-threaded merge join plan (5000ms) and much worse than the 2600ms for the parallel hash join. We seem to be going backwards! The logical reads for the parallel merge are still exactly the same as before, with no physical IOs. The cardinality estimates and thread distribution are also still very good (click to enlarge): A big clue to the reason for the poor performance is shown in the wait statistics (captured by Plan Explorer Pro): CXPACKET waits require careful interpretation, and are most often benign, but in this case excessive waiting occurs at the repartitioning exchanges. Unlike the parallel hash join, the repartitioning exchanges in this plan are order-preserving ‘merging’ exchanges (because merge join requires ordered inputs): Parallelism works best when threads can just grab any available unit of work and get on with processing it. Preserving order introduces inter-thread dependencies that can easily lead to significant waits occurring. In extreme cases, these dependencies can result in an intra-query deadlock, though the details of that will have to wait for another time to explore in detail. The potential for waits and deadlocks leads the query optimizer to cost parallel merge join relatively highly, especially as the degree of parallelism (DOP) increases. This high costing resulted in the optimizer choosing a serial merge join rather than parallel in this case. The test results certainly confirm its reasoning. Collocated Joins In SQL Server 2008 and later, the optimizer has another available strategy when joining tables that share a common partition scheme. This strategy is a collocated join, also known as as a per-partition join. It can be applied in both serial and parallel execution plans, though it is limited to 2-way joins in the current optimizer. Whether the optimizer chooses a collocated join or not depends on cost estimation. The primary benefits of a collocated join are that it eliminates an exchange and requires less memory, as we will see next. Costing and Plan Selection The query optimizer did consider a collocated join for our original query, but it was rejected on cost grounds. The parallel hash join with repartitioning exchanges appeared to be a cheaper option. There is no query hint to force a collocated join, so we have to mess with the costing framework to produce one for our test query. Pretending that IOs cost 50 times more than usual is enough to convince the optimizer to use collocated join with our test query: -- Pretend IOs are 50x cost temporarily DBCC SETIOWEIGHT(50);   -- Co-located hash join SELECT COUNT_BIG(*) FROM dbo.T1 AS T1 JOIN dbo.T2 AS T2 ON T2.TID = T1.TID OPTION (RECOMPILE);   -- Reset IO costing DBCC SETIOWEIGHT(1); Collocated Join Plan The estimated execution plan for the collocated join is: The Constant Scan contains one row for each partition of the shared partitioning scheme, from 1 to 41. The hash repartitioning exchanges seen previously are replaced by a single Distribute Streams exchange using Demand partitioning. Demand partitioning means that the next partition id is given to the next parallel thread that asks for one. My test machine has eight logical processors, and all are available for SQL Server to use. As a result, there are eight threads in the single parallel branch in this plan, each processing one partition from each table at a time. Once a thread finishes processing a partition, it grabs a new partition number from the Distribute Streams exchange…and so on until all partitions have been processed. It is important to understand that the parallel scans in this plan are different from the parallel hash join plan. Although the scans have the same parallelism icon, tables T1 and T2 are not being co-operatively scanned by multiple threads in the same way. Each thread reads a single partition of T1 and performs a hash match join with the same partition from table T2. The properties of the two Clustered Index Scans show a Seek Predicate (unusual for a scan!) limiting the rows to a single partition: The crucial point is that the join between T1 and T2 is on TID, and TID is the partitioning column for both tables. A thread that processes partition ‘n’ is guaranteed to see all rows that can possibly join on TID for that partition. In addition, no other thread will see rows from that partition, so this removes the need for repartitioning exchanges. CPU and Memory Efficiency Improvements The collocated join has removed two expensive repartitioning exchanges and added a single exchange processing 41 rows (one for each partition id). Remember, the parallel hash join plan exchanges had to process 5 million and 15 million rows. The amount of processor time spent on exchanges will be much lower in the collocated join plan. In addition, the collocated join plan has a maximum of 8 threads processing single partitions at any one time. The 41 partitions will all be processed eventually, but a new partition is not started until a thread asks for it. Threads can reuse hash table memory for the new partition. The parallel hash join plan also had 8 hash tables, but with all 5,000,000 build rows loaded at the same time. The collocated plan needs memory for only 8 * 125,000 = 1,000,000 rows at any one time. Collocated Hash Join Performance The collated join plan has disappointing performance in this case. The query runs for around 25,300ms despite the same IO statistics as usual. This is much the worst result so far, so what went wrong? It turns out that cardinality estimation for the single partition scans of table T1 is slightly low. The properties of the Clustered Index Scan of T1 (graphic immediately above) show the estimation was for 121,951 rows. This is a small shortfall compared with the 125,000 rows actually encountered, but it was enough to cause the hash join to spill to physical tempdb: A level 1 spill doesn’t sound too bad, until you realize that the spill to tempdb probably occurs for each of the 41 partitions. As a side note, the cardinality estimation error is a little surprising because the system tables accurately show there are 125,000 rows in every partition of T1. Unfortunately, the optimizer uses regular column and index statistics to derive cardinality estimates here rather than system table information (e.g. sys.partitions). Collocated Merge Join We will never know how well the collocated parallel hash join plan might have worked without the cardinality estimation error (and the resulting 41 spills to tempdb) but we do know: Merge join does not require a memory grant; and Merge join was the optimizer’s preferred join option for a single partition join Putting this all together, what we would really like to see is the same collocated join strategy, but using merge join instead of hash join. Unfortunately, the current query optimizer cannot produce a collocated merge join; it only knows how to do collocated hash join. So where does this leave us? CROSS APPLY sys.partitions We can try to write our own collocated join query. We can use sys.partitions to find the partition numbers, and CROSS APPLY to get a count per partition, with a final step to sum the partial counts. The following query implements this idea: SELECT row_count = SUM(Subtotals.cnt) FROM ( -- Partition numbers SELECT p.partition_number FROM sys.partitions AS p WHERE p.[object_id] = OBJECT_ID(N'T1', N'U') AND p.index_id = 1 ) AS P CROSS APPLY ( -- Count per collocated join SELECT cnt = COUNT_BIG(*) FROM dbo.T1 AS T1 JOIN dbo.T2 AS T2 ON T2.TID = T1.TID WHERE $PARTITION.PFT(T1.TID) = p.partition_number AND $PARTITION.PFT(T2.TID) = p.partition_number ) AS SubTotals; The estimated plan is: The cardinality estimates aren’t all that good here, especially the estimate for the scan of the system table underlying the sys.partitions view. Nevertheless, the plan shape is heading toward where we would like to be. Each partition number from the system table results in a per-partition scan of T1 and T2, a one-to-many Merge Join, and a Stream Aggregate to compute the partial counts. The final Stream Aggregate just sums the partial counts. Execution time for this query is around 3,500ms, with the same IO statistics as always. This compares favourably with 5,000ms for the serial plan produced by the optimizer with the OPTION (MERGE JOIN) hint. This is another case of the sum of the parts being less than the whole – summing 41 partial counts from 41 single-partition merge joins is faster than a single merge join and count over all partitions. Even so, this single-threaded collocated merge join is not as quick as the original parallel hash join plan, which executed in 2,600ms. On the positive side, our collocated merge join uses only one logical processor and requires no memory grant. The parallel hash join plan used 16 threads and reserved 569 MB of memory:   Using a Temporary Table Our collocated merge join plan should benefit from parallelism. The reason parallelism is not being used is that the query references a system table. We can work around that by writing the partition numbers to a temporary table (or table variable): SET STATISTICS IO ON; DECLARE @s datetime2 = SYSUTCDATETIME();   CREATE TABLE #P ( partition_number integer PRIMARY KEY);   INSERT #P (partition_number) SELECT p.partition_number FROM sys.partitions AS p WHERE p.[object_id] = OBJECT_ID(N'T1', N'U') AND p.index_id = 1;   SELECT row_count = SUM(Subtotals.cnt) FROM #P AS p CROSS APPLY ( SELECT cnt = COUNT_BIG(*) FROM dbo.T1 AS T1 JOIN dbo.T2 AS T2 ON T2.TID = T1.TID WHERE $PARTITION.PFT(T1.TID) = p.partition_number AND $PARTITION.PFT(T2.TID) = p.partition_number ) AS SubTotals;   DROP TABLE #P;   SELECT DATEDIFF(Millisecond, @s, SYSUTCDATETIME()); SET STATISTICS IO OFF; Using the temporary table adds a few logical reads, but the overall execution time is still around 3500ms, indistinguishable from the same query without the temporary table. The problem is that the query optimizer still doesn’t choose a parallel plan for this query, though the removal of the system table reference means that it could if it chose to: In fact the optimizer did enter the parallel plan phase of query optimization (running search 1 for a second time): Unfortunately, the parallel plan found seemed to be more expensive than the serial plan. This is a crazy result, caused by the optimizer’s cost model not reducing operator CPU costs on the inner side of a nested loops join. Don’t get me started on that, we’ll be here all night. In this plan, everything expensive happens on the inner side of a nested loops join. Without a CPU cost reduction to compensate for the added cost of exchange operators, candidate parallel plans always look more expensive to the optimizer than the equivalent serial plan. Parallel Collocated Merge Join We can produce the desired parallel plan using trace flag 8649 again: SELECT row_count = SUM(Subtotals.cnt) FROM #P AS p CROSS APPLY ( SELECT cnt = COUNT_BIG(*) FROM dbo.T1 AS T1 JOIN dbo.T2 AS T2 ON T2.TID = T1.TID WHERE $PARTITION.PFT(T1.TID) = p.partition_number AND $PARTITION.PFT(T2.TID) = p.partition_number ) AS SubTotals OPTION (QUERYTRACEON 8649); The actual execution plan is: One difference between this plan and the collocated hash join plan is that a Repartition Streams exchange operator is used instead of Distribute Streams. The effect is similar, though not quite identical. The Repartition uses round-robin partitioning, meaning the next partition id is pushed to the next thread in sequence. The Distribute Streams exchange seen earlier used Demand partitioning, meaning the next partition id is pulled across the exchange by the next thread that is ready for more work. There are subtle performance implications for each partitioning option, but going into that would again take us too far off the main point of this post. Performance The important thing is the performance of this parallel collocated merge join – just 1350ms on a typical run. The list below shows all the alternatives from this post (all timings include creation, population, and deletion of the temporary table where appropriate) from quickest to slowest: Collocated parallel merge join: 1350ms Parallel hash join: 2600ms Collocated serial merge join: 3500ms Serial merge join: 5000ms Parallel merge join: 8400ms Collated parallel hash join: 25,300ms (hash spill per partition) The parallel collocated merge join requires no memory grant (aside from a paltry 1.2MB used for exchange buffers). This plan uses 16 threads at DOP 8; but 8 of those are (rather pointlessly) allocated to the parallel scan of the temporary table. These are minor concerns, but it turns out there is a way to address them if it bothers you. Parallel Collocated Merge Join with Demand Partitioning This final tweak replaces the temporary table with a hard-coded list of partition ids (dynamic SQL could be used to generate this query from sys.partitions): SELECT row_count = SUM(Subtotals.cnt) FROM ( VALUES (1),(2),(3),(4),(5),(6),(7),(8),(9),(10), (11),(12),(13),(14),(15),(16),(17),(18),(19),(20), (21),(22),(23),(24),(25),(26),(27),(28),(29),(30), (31),(32),(33),(34),(35),(36),(37),(38),(39),(40),(41) ) AS P (partition_number) CROSS APPLY ( SELECT cnt = COUNT_BIG(*) FROM dbo.T1 AS T1 JOIN dbo.T2 AS T2 ON T2.TID = T1.TID WHERE $PARTITION.PFT(T1.TID) = p.partition_number AND $PARTITION.PFT(T2.TID) = p.partition_number ) AS SubTotals OPTION (QUERYTRACEON 8649); The actual execution plan is: The parallel collocated hash join plan is reproduced below for comparison: The manual rewrite has another advantage that has not been mentioned so far: the partial counts (per partition) can be computed earlier than the partial counts (per thread) in the optimizer’s collocated join plan. The earlier aggregation is performed by the extra Stream Aggregate under the nested loops join. The performance of the parallel collocated merge join is unchanged at around 1350ms. Final Words It is a shame that the current query optimizer does not consider a collocated merge join (Connect item closed as Won’t Fix). The example used in this post showed an improvement in execution time from 2600ms to 1350ms using a modestly-sized data set and limited parallelism. In addition, the memory requirement for the query was almost completely eliminated  – down from 569MB to 1.2MB. The problem with the parallel hash join selected by the optimizer is that it attempts to process the full data set all at once (albeit using eight threads). It requires a large memory grant to hold all 5 million rows from table T1 across the eight hash tables, and does not take advantage of the divide-and-conquer opportunity offered by the common partitioning. The great thing about the collocated join strategies is that each parallel thread works on a single partition from both tables, reading rows, performing the join, and computing a per-partition subtotal, before moving on to a new partition. From a thread’s point of view… If you have trouble visualizing what is happening from just looking at the parallel collocated merge join execution plan, let’s look at it again, but from the point of view of just one thread operating between the two Parallelism (exchange) operators. Our thread picks up a single partition id from the Distribute Streams exchange, and starts a merge join using ordered rows from partition 1 of table T1 and partition 1 of table T2. By definition, this is all happening on a single thread. As rows join, they are added to a (per-partition) count in the Stream Aggregate immediately above the Merge Join. Eventually, either T1 (partition 1) or T2 (partition 1) runs out of rows and the merge join stops. The per-partition count from the aggregate passes on through the Nested Loops join to another Stream Aggregate, which is maintaining a per-thread subtotal. Our same thread now picks up a new partition id from the exchange (say it gets id 9 this time). The count in the per-partition aggregate is reset to zero, and the processing of partition 9 of both tables proceeds just as it did for partition 1, and on the same thread. Each thread picks up a single partition id and processes all the data for that partition, completely independently from other threads working on other partitions. One thread might eventually process partitions (1, 9, 17, 25, 33, 41) while another is concurrently processing partitions (2, 10, 18, 26, 34) and so on for the other six threads at DOP 8. The point is that all 8 threads can execute independently and concurrently, continuing to process new partitions until the wider job (of which the thread has no knowledge!) is done. This divide-and-conquer technique can be much more efficient than simply splitting the entire workload across eight threads all at once. Related Reading Understanding and Using Parallelism in SQL Server Parallel Execution Plans Suck © 2013 Paul White – All Rights Reserved Twitter: @SQL_Kiwi

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  • SCVMM 2012 R2 - Installing Virtual Switch Fails with Error 2916

    - by Brian M.
    So I've been attempting to teach myself SCVMM 2012 and Hyper-V Server 2012 R2, and I seem to have hit a snag. I've connected my Hyper-V Host to SCVMM 2012 successfully, and created a logical network, logical switch, and uplink port profile (which I essentially blew through with the default settings). However when I attempt to create a virtual switch on my Hyper-V host, I run into an issue. The job will use my logical network settings I created to configure the virtual switch, but when it tries to apply it to the host, it stalls and eventually fails with the following error: Error (2916) VMM is unable to complete the request. The connection to the agent vmhost1.test.loc was lost. WinRM: URL: [h**p://vmhost1.test.loc:5985], Verb: [GET], Resource: [h**p://schemas.microsoft.com/wbem/wsman/1/wmi/root/virtualization/v2/Msvm_ConcreteJob?InstanceID=2F401A71-14A2-4636-9B3E-10C0EE942D33] Unknown error (0x80338126) Recommended Action Ensure that the Windows Remote Management (WinRM) service and the VMM agent are installed and running and that a firewall is not blocking HTTP/HTTPS traffic. Ensure that VMM server is able to communicate with econ-hyperv2.econ.loc over WinRM by successfully running the following command: winrm id –r:vmhost1.test.loc This problem can also be caused by a Windows Management Instrumentation (WMI) service crash. If the server is running Windows Server 2008 R2, ensure that KB 982293 (h**p://support.microsoft.com/kb/982293) is installed on it. If the error persists, restart vmhost1.test.loc and then try the operation again. Refer to h**p://support.microsoft.com/kb/2742275 for more details. I restarted the server, and upon booting am greeted with a message stating "No active network adapters found." I load up powershell and run "Get-NetAdapter -IncludeHidden" to see what's going on, and get the following: Name InterfaceDescription ifIndex Status ---- -------------------- ------- ----- Local Area Connection* 5 WAN Miniport (PPPOE) 6 Di... Ethernet Microsoft Hyper-V Network Switch Def... 10 Local Area Connection* 1 WAN Miniport (L2TP) 2 Di... Local Area Connection* 8 WAN Miniport (Network Monitor) 9 Up Local Area Connection* 4 WAN Miniport (PPTP) 5 Di... Ethernet 2 Broadcom NetXtreme Gigabit Ethernet 13 Up Local Area Connection* 7 WAN Miniport (IPv6) 8 Up Local Area Connection* 9 Microsoft Kernel Debug Network Adapter 11 No... Local Area Connection* 3 WAN Miniport (IKEv2) 4 Di... Local Area Connection* 2 WAN Miniport (SSTP) 3 Di... vSwitch (TEST Test Swi... Hyper-V Virtual Switch Extension Ada... 17 Up Local Area Connection* 6 WAN Miniport (IP) 7 Up Now the machine is no longer visible on the network, and I don't have the slightest idea what went wrong, and more importantly how to undo the damage I caused in order to get back to where I was (save for re-installing Hyper-V Server, but I really would rather know what's going on and how to fix it)! Does anybody have any ideas? Much appreciated!

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  • LVM mirror attempt results in "Insufficient free space"

    - by MattK
    Attempting to add a disk to mirror an LVM volume on CentOS 7 always fails with "Insufficient free space: 1 extents needed, but only 0 available". Having searched for a solution, I have tried specifying disks, multiple logging options, adding 3rd log partition, but have not found a solution Not sure if I am making a rookie mistake, or there is something more subtle wrong (I am more familiar with ZFS, new to using LVM): # lvconvert -m1 centos_bi/home Insufficient free space: 1 extents needed, but only 0 available # lvconvert -m1 --corelog centos_bi/home Insufficient free space: 1 extents needed, but only 0 available # lvconvert -m1 --corelog --alloc anywhere centos_bi/home Insufficient free space: 1 extents needed, but only 0 available # lvconvert -m1 --mirrorlog mirrored --alloc anywhere centos_bi/home /dev/sda2 Insufficient free space: 1 extents needed, but only 0 available # lvconvert -m1 --corelog --alloc anywhere centos_bi/home /dev/sdi2 /dev/sda2 Insufficient free space: 1 extents needed, but only 0 available The two disks are of the same size, and have identical partition layouts via "sfdisk -d /dev/sdi part_table; sfdisk /dev/sda < part_table". The current configuration is detailed below. # pvs PV VG Fmt Attr PSize PFree /dev/sda1 centos_bi lvm2 a-- 496.00m 496.00m /dev/sda2 centos_bi lvm2 a-- 465.27g 465.27g /dev/sdi2 centos_bi lvm2 a-- 465.27g 0 # vgs VG #PV #LV #SN Attr VSize VFree centos_bi 3 3 0 wz--n- 931.02g 465.75g # lvs -a -o +devices LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert Devices home centos_bi -wi-ao---- 391.64g /dev/sdi2(6050) root centos_bi -wi-ao---- 50.00g /dev/sdi2(106309) swap centos_bi -wi-ao---- 23.63g /dev/sdi2(0) # pvdisplay --- Physical volume --- PV Name /dev/sdi2 VG Name centos_bi PV Size 465.27 GiB / not usable 3.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 119109 Free PE 0 Allocated PE 119109 --- Physical volume --- PV Name /dev/sda2 VG Name centos_bi PV Size 465.27 GiB / not usable 3.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 119109 Free PE 119109 Allocated PE 0 --- Physical volume --- PV Name /dev/sda1 VG Name centos_bi PV Size 500.00 MiB / not usable 4.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 124 Free PE 124 Allocated PE 0 # vgdisplay --- Volume group --- VG Name centos_bi System ID Format lvm2 Metadata Areas 3 Metadata Sequence No 10 VG Access read/write VG Status resizable MAX LV 0 Cur LV 3 Open LV 3 Max PV 0 Cur PV 3 Act PV 3 VG Size 931.02 GiB PE Size 4.00 MiB Total PE 238342 Alloc PE / Size 119109 / 465.27 GiB Free PE / Size 119233 / 465.75 GiB # lvdisplay --- Logical volume --- LV Path /dev/centos_bi/swap LV Name swap VG Name centos_bi LV Write Access read/write LV Creation host, time localhost, 2014-08-07 16:34:34 -0400 LV Status available # open 2 LV Size 23.63 GiB Current LE 6050 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:1 --- Logical volume --- LV Path /dev/centos_bi/home LV Name home VG Name centos_bi LV Write Access read/write LV Creation host, time localhost, 2014-08-07 16:34:35 -0400 LV Status available # open 1 LV Size 391.64 GiB Current LE 100259 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:2 --- Logical volume --- LV Path /dev/centos_bi/root LV Name root VG Name centos_bi LV Write Access read/write LV Creation host, time localhost, 2014-08-07 16:34:37 -0400 LV Status available # open 1 LV Size 50.00 GiB Current LE 12800 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0

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  • Configuring RAID1 on HP Proliant Microserver N54L / Ubuntu 14.04.1 LTS [duplicate]

    - by Chris Beach
    This question already has an answer here: Cant find my harddrives in ubuntu installation? 2 answers I've bought a N54L and fitted two 3GB drives. Keen to get set up with RAID1. BIOS: SATA controller mode set to "RAID" RAID Option ROM utility: both physical drives set up as one logical drive When I came to install Ubuntu (14.04.1), both drives appeared during the setup process. I was only expecting to see the logical drive, although I'm a complete novice with RAID. I've read that the HP Proliant Microservers don't have "proper" RAID support, and require some kind of driver to be installed. I've tried a few HP utilities from the following apt repo: deb http://downloads.linux.hp.com/SDR/repo/mcp wheezy/current non-free On installation, most say "server not supported" Would appreciate your advice.

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  • Disk is spinning down each minute, unable to disable it

    - by lzap
    I played with spindown and APM settings of my Samsung discs and now they spin down every minute. I want to disable it, but it seems it does not accept any of the spindown time or APM values. Nothing works, it's all the same. Please help what values should be proper for it. I do not want it to spin down at all. /dev/sda: ATA device, with non-removable media Model Number: SAMSUNG HD154UI Serial Number: S1Y6J1KZ206527 Firmware Revision: 1AG01118 Standards: Used: ATA-8-ACS revision 3b Supported: 7 6 5 4 Configuration: Logical max current cylinders 16383 16383 heads 16 16 sectors/track 63 63 -- CHS current addressable sectors: 16514064 LBA user addressable sectors: 268435455 LBA48 user addressable sectors: 2930277168 Logical/Physical Sector size: 512 bytes device size with M = 1024*1024: 1430799 MBytes device size with M = 1000*1000: 1500301 MBytes (1500 GB) cache/buffer size = unknown Capabilities: LBA, IORDY(can be disabled) Queue depth: 32 Standby timer values: spec'd by Standard, no device specific minimum R/W multiple sector transfer: Max = 16 Current = 16 Advanced power management level: 60 Recommended acoustic management value: 254, current value: 0 DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6 udma7 Cycle time: min=120ns recommended=120ns PIO: pio0 pio1 pio2 pio3 pio4 Cycle time: no flow control=120ns IORDY flow control=120ns Commands/features: Enabled Supported: * SMART feature set Security Mode feature set * Power Management feature set * Write cache * Look-ahead * Host Protected Area feature set * WRITE_BUFFER command * READ_BUFFER command * NOP cmd * DOWNLOAD_MICROCODE * Advanced Power Management feature set Power-Up In Standby feature set * SET_FEATURES required to spinup after power up SET_MAX security extension Automatic Acoustic Management feature set * 48-bit Address feature set * Device Configuration Overlay feature set * Mandatory FLUSH_CACHE * FLUSH_CACHE_EXT * SMART error logging * SMART self-test Media Card Pass-Through * General Purpose Logging feature set * 64-bit World wide name * WRITE_UNCORRECTABLE_EXT command * {READ,WRITE}_DMA_EXT_GPL commands * Segmented DOWNLOAD_MICROCODE * Gen1 signaling speed (1.5Gb/s) * Gen2 signaling speed (3.0Gb/s) * Native Command Queueing (NCQ) * Host-initiated interface power management * Phy event counters * NCQ priority information DMA Setup Auto-Activate optimization Device-initiated interface power management * Software settings preservation * SMART Command Transport (SCT) feature set * SCT Long Sector Access (AC1) * SCT LBA Segment Access (AC2) * SCT Error Recovery Control (AC3) * SCT Features Control (AC4) * SCT Data Tables (AC5) Security: Master password revision code = 65534 supported not enabled not locked frozen not expired: security count supported: enhanced erase 326min for SECURITY ERASE UNIT. 326min for ENHANCED SECURITY ERASE UNIT. Logical Unit WWN Device Identifier: 50024e900300cca3 NAA : 5 IEEE OUI : 0024e9 Unique ID : 00300cca3 Checksum: correct I have the very same disc which I did not "tuned" and it does not spin. But I do not know where to read the settings from. The hdparm only shows this: Advanced power management level: 60 Recommended acoustic management value: 254, current value: 0 Edit: It seems the issue was tuned daemon in RHEL6. It was too aggressive, I turned off disc tuning and it seems they are no longer spinning down.

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  • LUKS with LVM, mount is not persistent after reboot

    - by linxsaga
    I have created a Logical vol and used luks to encrypt it. But while rebooting the server. I get a error message (below), therefore I would have to enter the root pass and disable the /etc/fstab entry. So mount of the LUKS partition is not persistent during reboot using LUKS. I have this setup on RHEL6 and wondering what i could be missing. I want to the LV to get be mount on reboot. Later I would want to replace it with UUID instead of the device name. Error message on reboot: "Give root password for maintenance (or type Control-D to continue):" Here are the steps from the beginning: [root@rhel6 ~]# pvcreate /dev/sdb Physical volume "/dev/sdb" successfully created [root@rhel6 ~]# vgcreate vg01 /dev/sdb Volume group "vg01" successfully created [root@rhel6 ~]# lvcreate --size 500M -n lvol1 vg01 Logical volume "lvol1" created [root@rhel6 ~]# lvdisplay --- Logical volume --- LV Name /dev/vg01/lvol1 VG Name vg01 LV UUID nX9DDe-ctqG-XCgO-2wcx-ddy4-i91Y-rZ5u91 LV Write Access read/write LV Status available # open 0 LV Size 500.00 MiB Current LE 125 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0 [root@rhel6 ~]# cryptsetup luksFormat /dev/vg01/lvol1 WARNING! ======== This will overwrite data on /dev/vg01/lvol1 irrevocably. Are you sure? (Type uppercase yes): YES Enter LUKS passphrase: Verify passphrase: [root@rhel6 ~]# mkdir /house [root@rhel6 ~]# cryptsetup luksOpen /dev/vg01/lvol1 house Enter passphrase for /dev/vg01/lvol1: [root@rhel6 ~]# mkfs.ext4 /dev/mapper/house mke2fs 1.41.12 (17-May-2010) Filesystem label= OS type: Linux Block size=1024 (log=0) Fragment size=1024 (log=0) Stride=0 blocks, Stripe width=0 blocks 127512 inodes, 509952 blocks 25497 blocks (5.00%) reserved for the super user First data block=1 Maximum filesystem blocks=67633152 63 block groups 8192 blocks per group, 8192 fragments per group 2024 inodes per group Superblock backups stored on blocks: 8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409 Writing inode tables: done Creating journal (8192 blocks): done Writing superblocks and filesystem accounting information: done This filesystem will be automatically checked every 21 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override. [root@rhel6 ~]# mount -t ext4 /dev/mapper/house /house PS: HERE I have successfully mounted: [root@rhel6 ~]# ls /house/ lost+found [root@rhel6 ~]# vim /etc/fstab -> as follow /dev/mapper/house /house ext4 defaults 1 2 [root@rhel6 ~]# vim /etc/crypttab -> entry as follows house /dev/vg01/lvol1 password [root@rhel6 ~]# mount -o remount /house [root@rhel6 ~]# ls /house/ lost+found [root@rhel6 ~]# umount /house/ [root@rhel6 ~]# mount -a -> SUCCESSFUL AGAIN [root@rhel6 ~]# ls /house/ lost+found Please let me know if I am missing anything here. Thanks in advance.

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  • “Disk /dev/xvda1 doesn't contain a valid partition table”

    - by Simpanoz
    Iam newbie to EC2 and Ubuntu 11 (EC2 Free tier Ubuntu). I have made following commands. sudo mkfs -t ext4 /dev/xvdf6 sudo mkdir /db sudo vim /etc/fstab /dev/xvdf6 /db ext4 noatime,noexec,nodiratime 0 0 sudo mount /dev/xvdf6 /db fdisk -l I got following output. Can some one guide me what I am doing wrong and how it can be rectified. Disk /dev/xvda1: 8589 MB, 8589934592 bytes 255 heads, 63 sectors/track, 1044 cylinders, total 16777216 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/xvda1 doesn't contain a valid partition table Disk /dev/xvdf6: 6442 MB, 6442450944 bytes 255 heads, 63 sectors/track, 783 cylinders, total 12582912 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/xvdf6 doesn't contain a valid partition table.

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  • Can't connect disk management to remote XP PC from local Win7/Server 2008

    - by Grez
    Scenario as follows: support technicians using Windows 7 PC's or Server 2008 terminal server are unable to connect Disk Management MMC snap in to a remote PC when the remote device is running Windows XP. "Disk management could not start Virtual Disk Service (VDS) on ". This can happen if the remote computer does not support VDS, or if a connection cannot be established because it was blocked by Windows Firewall." Connecting from another XP machine or 2003 server to the same XP machines works fine. Even connecting from XP/2003 to the Win7 or 2008 server works fine. Windows firewall disabled on all devices. I'm guessing this is something to do with the fact that XP uses logical disk manager service whereas Win7/2008 use Virtual disk manager service. But there doesn't seem to be any way to use logical disk manager service from 7/2008 to connect to XP...

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  • RAID P410i and P812 performance issues

    - by Alexey
    I'm having much trouble with I/O performance of HP DL360 server with two RAID controllers - P410i and P812, Windows Server 2008, 36 GiB RAM and 16 x Intel Xeon x5550. The server runs a bunch of tasks producing heavy sequential I/O, and after about 20-30 minutes of intensive work it looks like the tasks are stuck, not using CPU and with enough free memory (so this cannot be a bottleneck). The same tasks were running quite well on the older server (Windows Server 2003, 4 x Intel Xeon, 12 GiB RAM). RAID cache is present, write-cache battery is installed. Cache is configured as 25% readahead/75% writeback. The swap file resides on the logical disk served by P410i and other logical disks are on P812. Can someone tell me what can be the matter of this? Is this a hardware problem or misconfiguration?

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  • Server-to-Switch Trunking in Procurve switch, what does this mean?

    - by MattUebel
    I am looking to set up switch redundancy in a new datacenter environment. IEEE 802.3ad seems to be the go-to concept on this, at least when paired with a technology that gets around the "single switch" limitation for the link aggregation. Looking through the brochure for a procurve switch I see: Server-to-Switch Distributed Trunking, which allows a server to connect to two switches with one logical trunk; increases resiliency and enables load sharing in virtualized data centers http://www.procurve.com/docs/products/brochures/5400_3500%20Product%20Brochure4AA0-4236ENW.pdf I am trying to figure out how this relates to the 802.3a standard, as it seems that it would give me what I want (one server has 2 nics, each of which is connected to separate switches, together forming a single logical nic which would provide the happy redundancy we want), but I guess I am looking for someone familiar with this concept and could add to it.

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  • What is "2LUN" mode in connection with RAID?

    - by naxa
    I've came across RAID products that also list JBOD (just a bunch of disks) mode and 2LUN mode. What the heck is 2LUN mode? I could not find a description; the closest thing seems to be LUN 'logical unit number' but I don't get the 2LUN thing. UPDATE 1 This is what Wikipedia has to say about JBOD: JBOD (derived from "just a bunch of disks"): an architecture involving multiple hard drives, while making them accessible either as independent hard drives, or as a combined (spanned) single logical volume with no actual RAID functionality. So JBOD can actually mean two different (albeit related) things. Answer of Guest says 2LUN means no spanning. Does this suggest that 2LUN would simply mean the JBOD-variant with no span?

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  • High I/O latency with software RAID, LUKS encrypted and LVM partitioned KVM setup

    - by aef
    I found out a performance problems with a Mumble server, which I described in a previous question are caused by an I/O latency problem of unknown origin. As I have no idea what is causing this and how to further debug it, I'm asking for your ideas on the topic. I'm running a Hetzner EX4S root server as KVM hypervisor. The server is running Debian Wheezy Beta 4 and KVM virtualisation is utilized through LibVirt. The server has two different 3TB hard drives as one of the hard drives was replaced after S.M.A.R.T. errors were reported. The first hard disk is a Seagate Barracuda XT ST33000651AS (512 bytes logical, 4096 bytes physical sector size), the other one a Seagate Barracuda 7200.14 (AF) ST3000DM001-9YN166 (512 bytes logical and physical sector size). There are two Linux software RAID1 devices. One for the unencrypted boot partition and one as container for the encrypted rest, using both hard drives. Inside the latter RAID device lies an AES encrypted LUKS container. Inside the LUKS container there is a LVM physical volume. The hypervisor's VFS is split on three logical volumes on the described LVM physical volume: one for /, one for /home and one for swap. Here is a diagram of the block device configuration stack: sda (Physical HDD) - md0 (RAID1) - md1 (RAID1) sdb (Physical HDD) - md0 (RAID1) - md1 (RAID1) md0 (Boot RAID) - ext4 (/boot) md1 (Data RAID) - LUKS container - LVM Physical volume - LVM volume hypervisor-root - LVM volume hypervisor-home - LVM volume hypervisor-swap - … (Virtual machine volumes) The guest systems (virtual machines) are mostly running Debian Wheezy Beta 4 too. We have one additional Ubuntu Precise instance. They get their block devices from the LVM physical volume, too. The volumes are accessed through Virtio drivers in native writethrough mode. The IO scheduler (elevator) on both the hypervisor and the guest system is set to deadline instead of the default cfs as that happened to be the most performant setup according to our bonnie++ test series. The I/O latency problem is experienced not only inside the guest systems but is also affecting services running on the hypervisor system itself. The setup seems complex, but I'm sure that not the basic structure causes the latency problems, as my previous server ran four years with almost the same basic setup, without any of the performance problems. On the old setup the following things were different: Debian Lenny was the OS for both hypervisor and almost all guests Xen software virtualisation (therefore no Virtio, also) no LibVirt management Different hard drives, each 1.5TB in size (one of them was a Seagate Barracuda 7200.11 ST31500341AS, the other one I can't tell anymore) We had no IPv6 connectivity Neither in the hypervisor nor in guests we had noticable I/O latency problems According the the datasheets, the current hard drives and the one of the old machine have an average latency of 4.12ms.

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  • VMWare esxi 4.1 storage errors with MD3200

    - by Karl Katzke
    We're seeing some storage errors from the esxi logs relating to our MD3200. I'm sort of a VMWare noob and am not sure where to go from here because I couldn't find a lot of documentation on the VMWare website, and the forums didn't seem to have any posts about it with actual answers. Everything is working, but I'm trying to proactively troubleshoot this. sfcb-vmware_base|StoragePool Cannot get logical disk data from controller 0 sfcb-vmware_base|Volume Cannot get logical disk data from controller 0 sfcb-vmware_base|storelib-GetLDList-ProcessLibCommandCall failed; rval = 0x800E The ESXi boxes are connected directly via SAS to the controller on the MD3200. What do these errors actually mean, and what's a good path to start troubleshooting or solving them?

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  • Installing Solaris with Window. Disk partitioning problem.

    - by RishiPatel
    I am running windows and want to install the solaris but having hard time while using installer. I have 1 primary partition of 40GB and one extended partition. Extended partition have 4 logical drive. Solaris disk management window show only two partition one is of 40GB(Primary) and second is Extended partition. Can i convert a logical drive into primary partition( I have one free of 25 GB). Please look at the screenshot of disk management utitlity of window. http://img195.imageshack.us/img195/2005/20726948.jpg Is there any way to install solaris without reformatting the and repartitioning whole drive? In case it is not possible how should i partition and using which utility ?

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