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• Strange Recurrent Excessive I/O Wait

  - by Chris

  I know quite well that I/O wait has been discussed multiple times on this site, but all the other topics seem to cover constant I/O latency, while the I/O problem we need to solve on our server occurs at irregular (short) intervals, but is ever-present with massive spikes of up to 20k ms a-wait and service times of 2 seconds. The disk affected is /dev/sdb (Seagate Barracuda, for details see below). A typical iostat -x output would at times look like this, which is an extreme sample but by no means rare: iostat (Oct 6, 2013) tps rd_sec/s wr_sec/s avgrq-sz avgqu-sz await svctm %util 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 16.00 0.00 156.00 9.75 21.89 288.12 36.00 57.60 5.50 0.00 44.00 8.00 48.79 2194.18 181.82 100.00 2.00 0.00 16.00 8.00 46.49 3397.00 500.00 100.00 4.50 0.00 40.00 8.89 43.73 5581.78 222.22 100.00 14.50 0.00 148.00 10.21 13.76 5909.24 68.97 100.00 1.50 0.00 12.00 8.00 8.57 7150.67 666.67 100.00 0.50 0.00 4.00 8.00 6.31 10168.00 2000.00 100.00 2.00 0.00 16.00 8.00 5.27 11001.00 500.00 100.00 0.50 0.00 4.00 8.00 2.96 17080.00 2000.00 100.00 34.00 0.00 1324.00 9.88 1.32 137.84 4.45 59.60 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 22.00 44.00 204.00 11.27 0.01 0.27 0.27 0.60 Let me provide you with some more information regarding the hardware. It's a Dell 1950 III box with Debian as OS where uname -a reports the following: Linux xx 2.6.32-5-amd64 #1 SMP Fri Feb 15 15:39:52 UTC 2013 x86_64 GNU/Linux The machine is a dedicated server that hosts an online game without any databases or I/O heavy applications running. The core application consumes about 0.8 of the 8 GBytes RAM, and the average CPU load is relatively low. The game itself, however, reacts rather sensitive towards I/O latency and thus our players experience massive ingame lag, which we would like to address as soon as possible. iostat: avg-cpu: %user %nice %system %iowait %steal %idle 1.77 0.01 1.05 1.59 0.00 95.58 Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sdb 13.16 25.42 135.12 504701011 2682640656 sda 1.52 0.74 20.63 14644533 409684488 Uptime is: 19:26:26 up 229 days, 17:26, 4 users, load average: 0.36, 0.37, 0.32 Harddisk controller: 01:00.0 RAID bus controller: LSI Logic / Symbios Logic MegaRAID SAS 1078 (rev 04) Harddisks: Array 1, RAID-1, 2x Seagate Cheetah 15K.5 73 GB SAS Array 2, RAID-1, 2x Seagate ST3500620SS Barracuda ES.2 500GB 16MB 7200RPM SAS Partition information from df: Filesystem 1K-blocks Used Available Use% Mounted on /dev/sdb1 480191156 30715200 425083668 7% /home /dev/sda2 7692908 437436 6864692 6% / /dev/sda5 15377820 1398916 13197748 10% /usr /dev/sda6 39159724 19158340 18012140 52% /var Some more data samples generated with iostat -dx sdb 1 (Oct 11, 2013) Device: rrqm/s wrqm/s r/s w/s rsec/s wsec/s avgrq-sz avgqu-sz await svctm %util sdb 0.00 15.00 0.00 70.00 0.00 656.00 9.37 4.50 1.83 4.80 33.60 sdb 0.00 0.00 0.00 2.00 0.00 16.00 8.00 12.00 836.00 500.00 100.00 sdb 0.00 0.00 0.00 3.00 0.00 32.00 10.67 9.96 1990.67 333.33 100.00 sdb 0.00 0.00 0.00 4.00 0.00 40.00 10.00 6.96 3075.00 250.00 100.00 sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4.00 0.00 0.00 100.00 sdb 0.00 0.00 0.00 2.00 0.00 16.00 8.00 2.62 4648.00 500.00 100.00 sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.00 0.00 0.00 100.00 sdb 0.00 0.00 0.00 1.00 0.00 16.00 16.00 1.69 7024.00 1000.00 100.00 sdb 0.00 74.00 0.00 124.00 0.00 1584.00 12.77 1.09 67.94 6.94 86.00 Characteristic charts generated with rrdtool can be found here: iostat plot 1, 24 min interval: http://imageshack.us/photo/my-images/600/yqm3.png/ iostat plot 2, 120 min interval: http://imageshack.us/photo/my-images/407/griw.png/ As we have a rather large cache of 5.5 GBytes, we thought it might be a good idea to test if the I/O wait spikes would perhaps be caused by cache miss events. Therefore, we did a sync and then this to flush the cache and buffers: echo 3 > /proc/sys/vm/drop_caches and directly afterwards the I/O wait and service times virtually went through the roof, and everything on the machine felt like slow motion. During the next few hours the latency recovered and everything was as before - small to medium lags in short, unpredictable intervals. Now my question is: does anybody have any idea what might cause this annoying behaviour? Is it the first indication of the disk array or the raid controller dying, or something that can be easily mended by rebooting? (At the moment we're very reluctant to do this, however, because we're afraid that the disks might not come back up again.) Any help is greatly appreciated. Thanks in advance, Chris. Edited to add: we do see one or two processes go to 'D' state in top, one of which seems to be kjournald rather frequently. If I'm not mistaken, however, this does not indicate the processes causing the latency, but rather those affected by it - correct me if I'm wrong. Does the information about uninterruptibly sleeping processes help us in any way to address the problem? @Andy Shinn requested smartctl data, here it is: smartctl -a -d megaraid,2 /dev/sdb yields: smartctl 5.40 2010-07-12 r3124 [x86_64-unknown-linux-gnu] (local build) Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net Device: SEAGATE ST3500620SS Version: MS05 Serial number: Device type: disk Transport protocol: SAS Local Time is: Mon Oct 14 20:37:13 2013 CEST Device supports SMART and is Enabled Temperature Warning Disabled or Not Supported SMART Health Status: OK Current Drive Temperature: 20 C Drive Trip Temperature: 68 C Elements in grown defect list: 0 Vendor (Seagate) cache information Blocks sent to initiator = 1236631092 Blocks received from initiator = 1097862364 Blocks read from cache and sent to initiator = 1383620256 Number of read and write commands whose size <= segment size = 531295338 Number of read and write commands whose size > segment size = 51986460 Vendor (Seagate/Hitachi) factory information number of hours powered up = 36556.93 number of minutes until next internal SMART test = 32 Error counter log: Errors Corrected by Total Correction Gigabytes Total ECC rereads/ errors algorithm processed uncorrected fast | delayed rewrites corrected invocations [10^9 bytes] errors read: 509271032 47 0 509271079 509271079 20981.423 0 write: 0 0 0 0 0 5022.039 0 verify: 1870931090 196 0 1870931286 1870931286 100558.708 0 Non-medium error count: 0 SMART Self-test log Num Test Status segment LifeTime LBA_first_err [SK ASC ASQ] Description number (hours) # 1 Background short Completed 16 36538 - [- - -] # 2 Background short Completed 16 36514 - [- - -] # 3 Background short Completed 16 36490 - [- - -] # 4 Background short Completed 16 36466 - [- - -] # 5 Background short Completed 16 36442 - [- - -] # 6 Background long Completed 16 36420 - [- - -] # 7 Background short Completed 16 36394 - [- - -] # 8 Background short Completed 16 36370 - [- - -] # 9 Background long Completed 16 36364 - [- - -] #10 Background short Completed 16 36361 - [- - -] #11 Background long Completed 16 2 - [- - -] #12 Background short Completed 16 0 - [- - -] Long (extended) Self Test duration: 6798 seconds [113.3 minutes] smartctl -a -d megaraid,3 /dev/sdb yields: smartctl 5.40 2010-07-12 r3124 [x86_64-unknown-linux-gnu] (local build) Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net Device: SEAGATE ST3500620SS Version: MS05 Serial number: Device type: disk Transport protocol: SAS Local Time is: Mon Oct 14 20:37:26 2013 CEST Device supports SMART and is Enabled Temperature Warning Disabled or Not Supported SMART Health Status: OK Current Drive Temperature: 19 C Drive Trip Temperature: 68 C Elements in grown defect list: 0 Vendor (Seagate) cache information Blocks sent to initiator = 288745640 Blocks received from initiator = 1097848399 Blocks read from cache and sent to initiator = 1304149705 Number of read and write commands whose size <= segment size = 527414694 Number of read and write commands whose size > segment size = 51986460 Vendor (Seagate/Hitachi) factory information number of hours powered up = 36596.83 number of minutes until next internal SMART test = 28 Error counter log: Errors Corrected by Total Correction Gigabytes Total ECC rereads/ errors algorithm processed uncorrected fast | delayed rewrites corrected invocations [10^9 bytes] errors read: 610862490 44 0 610862534 610862534 20470.133 0 write: 0 0 0 0 0 5022.480 0 verify: 2861227413 203 0 2861227616 2861227616 100872.443 0 Non-medium error count: 1 SMART Self-test log Num Test Status segment LifeTime LBA_first_err [SK ASC ASQ] Description number (hours) # 1 Background short Completed 16 36580 - [- - -] # 2 Background short Completed 16 36556 - [- - -] # 3 Background short Completed 16 36532 - [- - -] # 4 Background short Completed 16 36508 - [- - -] # 5 Background short Completed 16 36484 - [- - -] # 6 Background long Completed 16 36462 - [- - -] # 7 Background short Completed 16 36436 - [- - -] # 8 Background short Completed 16 36412 - [- - -] # 9 Background long Completed 16 36404 - [- - -] #10 Background short Completed 16 36401 - [- - -] #11 Background long Completed 16 2 - [- - -] #12 Background short Completed 16 0 - [- - -] Long (extended) Self Test duration: 6798 seconds [113.3 minutes]

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• Check if serial port is listening

  - by Hyposaurus

  I have an Arduino sending and receiving instructions with a python script via a serial port. The Arduino takes a button state and when it is pushed it will send a message via serial to a python script and await a response. (via Serial.available()). Works well enough. However if the python script has crashed for whatever reason (ideally it will run in the background, so cant be easily checked) the Arduino will wait forever and even on a script restart will we unavailable. Is there a way for my Arduino to check if there is something listening on the serial port? (and alert me with flashing lights etc if not) or is this not how serial works? Worst case I guess I could use a timeout, although that is not ideal.

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• Update JSON file C# W8 development

  - by AndrewB

  At the moment, I've got a JSON file with content looking like this: { "username": "test", "someNumber":100 } I'm using JSON.Net to fetch the .JSON file from a webserver - C#: var http = new HttpClient(); http.MaxResponseContentBufferSize = Int32.MaxValue; var response = await http.GetStringAsync(URI); var result = JsonConvert.DeserializeObject<DatClass.Result>(response); This works great together with the class getting/setting the properties. However, what I would like to know is whether there's a good way for a user to update the .JSON file through a textbox UI? As in: [textbox - update username] [update button] - username sent to server - .JSON file updated - [textblock - showing updated username in UI]. I'm not looking for exact code solutions, I'm rather looking for good solutions on this, and/or if this is a terrible idea of an easy database(?).

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• Task.wait not working as I imagined

  - by user2357446

  I am trying to download a file, wait for the file to finish downloading, and then read the file afterwards. I have the following methods to do this: private async Task startDownload(string link, string savePath) { WebClient client = new WebClient(); client.DownloadProgressChanged += new DownloadProgressChangedEventHandler(client_DownloadProgressChanged); client.DownloadFileCompleted += new AsyncCompletedEventHandler(client_DownloadFileCompleted); await client.DownloadFileTaskAsync(new Uri(link), savePath); } private void checkUpdateButton_Click(object sender, EventArgs e) { Task task = Task.Factory.StartNew(() => startDownload(versionLink, versionSaveTo)); task.Wait(); if (task.IsCompleted) { checkVersion(); } } The checkVersion() method reads the file that was downloaded. This is throwing an IOException saying that the file is in use by something else and cannot be read. I thought that having task.Wait would prevent the rest of the method from executing until the task was finished?

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• Email Sending Task in Windows Phone Universal App

  - by Tanvir Sourov

  I was trying to write an Email sending code for Windows Phone Universal App. This is the Code that I have written in my Event Handler: Windows.ApplicationModel.Email.EmailMessage email = new Windows.ApplicationModel.Email.EmailMessage(); email.Subject = "Good morning"; email.Body = "Hello, how are you?"; var emailRecipient = new Windows.ApplicationModel.Email.EmailRecipient(email.Address); email.To.Add(emailRecipient); await Windows.ApplicationModel.Email.EmailManager.ShowComposeNewEmailAsync(emailMessage); This code works for my Windows Phone 8.1 App. But it's not working in the Universal App. Shall I have to add any reference? Is there any way to make it work in the Universal app? Thanks a lot. :)

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• Tomcat thread waiting on and locking the same resource

  - by Adam Matan

  Consider the following Java\Tomcat thread dump: "http-0.0.0.0-4080-4" daemon prio=10 tid=0x0000000019a2b000 nid=0x360e in Object.wait() [0x0000000040b71000] java.lang.Thread.State: WAITING (on object monitor) at java.lang.Object.wait(Native Method) - waiting on <0x00002ab5565fe358> (a org.apache.tomcat.util.net.JIoEndpoint$Worker) at java.lang.Object.wait(Object.java:485) at org.apache.tomcat.util.net.JIoEndpoint$Worker.await(JIoEndpoint.java:458) - locked <0x00002ab5565fe358> (a org.apache.tomcat.util.net.JIoEndpoint$Worker) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:484) at java.lang.Thread.run(Thread.java:662) Is this a deadlock? It seems that the same resource (0x00002ab5565fe358) is both locked and waited on - what does it mean?

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• Android: Access to an already paired connection

  - by poeschlorn

  Hi community, I have a question on accessing already existing paired bluetooth connections... How can a remote service detect an already paired connection and await a file transfer from it? In all comments on stackoverflow, on tutorials, ebooks or on google there is always shown how to create a new connection using sockets and so on, but no word about accessing to an existing one. Is it possible at all? If yes, can you also tell/show me how? At the moment I have no clue how to get started with it. Would be great if someone can help me get started :)

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• C# Deserializing to a dictionary<string, Object>

  - by lovecraft

  I'm writing a C#/VB application to connect to a database and do stuff with the data. I was given this code to take a serialized byte array and deserialized it, which is then written to a Dictionary The line of code is: Dictionary<string, Object> DictionaryEmployee = (Dictionary<string, Object> Deserializer(byteArrayEmp)); The errors I'm getting are exceedingly unhelpful. "Only assignment, call, increment, decrement, await, and new object expressions can be used as a statement" if I mouse over Object and "Using the generic type 'System.Collections.Generic.Dictionary' requires 2 type arguments if I mouse over Dictionary.

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• 64-bit 13.10 shows 1GB less RAM than 64-bit 13.04 did

  - by kiloseven

  Multiple 64-bit versions (Kubuntu, Lubuntu and Xubuntu) once installed on my ThinkPad R60 show 3GB of RAM, not the correct 4GB of RAM. Last week with 13.04, I had 4GB of RAM (which matches the BIOS) and this week I have 3GB available. Inquiring minds want to know. Details follow: Linux R60 3.11.0-12-generic #19-Ubuntu SMP Wed Oct 9 16:20:46 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux r60 free -m reports: _ total used free shared buffers cached Mem: 3001 854 2146 0 22 486 -/+ buffers/cache: 346 2655 Swap: 0 0 0 . . . . . . lshw shows: description: Notebook product: 9459AT8 () vendor: LENOVO version: ThinkPad R60/R60i serial: redacted width: 64 bits capabilities: smbios-2.4 dmi-2.4 vsyscall32 configuration: administrator_password=disabled boot=normal chassis=notebook family=ThinkPad R60/R60i frontpanel_password=unknown keyboard_password=disabled power-on_password=disabled uuid=126E4001-48CA-11CB-9D53-B982AE0D1ABB *-core description: Motherboard product: 9459AT8 vendor: LENOVO physical id: 0 version: Not Available *-firmware description: BIOS vendor: LENOVO physical id: 0 version: 7CETC1WW (2.11 ) date: 01/09/2007 size: 144KiB capacity: 1984KiB capabilities: pci pcmcia pnp upgrade shadowing escd cdboot bootselect socketedrom edd acpi usb biosbootspecification {snip} *-memory description: System Memory physical id: 29 slot: System board or motherboard size: 4GiB *-bank:0 description: SODIMM DDR2 Synchronous physical id: 0 slot: DIMM 1 size: 2GiB width: 64 bits *-bank:1 description: SODIMM DDR2 Synchronous physical id: 1 slot: DIMM 2 size: 2GiB width: 64 bits dpkg -l linux-* returns: Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) ||/ Name Version Description +++-======================================-=======================================-========================================================================== un linux-doc-3.2.0 (no description available) ii linux-firmware 1.79.6 Firmware for Linux kernel drivers ii linux-generic 3.2.0.52.62 Complete Generic Linux kernel un linux-headers (no description available) un linux-headers-3 (no description available) un linux-headers-3.0 (no description available) un linux-headers-3.2.0-23 (no description available) un linux-headers-3.2.0-23-generic (no description available) ii linux-headers-3.2.0-52 3.2.0-52.78 Header files related to Linux kernel version 3.2.0 ii linux-headers-3.2.0-52-generic 3.2.0-52.78 Linux kernel headers for version 3.2.0 on 64 bit x86 SMP ii linux-headers-generic 3.2.0.52.62 Generic Linux kernel headers un linux-image (no description available) un linux-image-3.0 (no description available) ii linux-image-3.2.0-52-generic 3.2.0-52.78 Linux kernel image for version 3.2.0 on 64 bit x86 SMP ii linux-image-generic 3.2.0.52.62 Generic Linux kernel image un linux-initramfs-tool (no description available) un linux-kernel-headers (no description available) un linux-kernel-log-daemon (no description available) ii linux-libc-dev 3.2.0-52.78 Linux Kernel Headers for development un linux-restricted-common (no description available) ii linux-sound-base 1.0.25+dfsg-0ubuntu1.1 base package for ALSA and OSS sound systems un linux-source-3.2.0 (no description available) un linux-tools (no description available)

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• AWS .NET SDK v2: the message-pump pattern

  - by Elton Stoneman

  Originally posted on: http://geekswithblogs.net/EltonStoneman/archive/2013/10/11/aws-.net-sdk-v2--the-message-pump-pattern.aspxVersion 2 of the AWS SDK for .NET has had a few pre-release iterations on NuGet and is stable, if a bit lacking in step-by-step guides. There’s at least one big reason to try it out: the SQS queue client now supports asynchronous reads, so you don’t need a clumsy polling mechanism to retrieve messages. The new approach  is easy to use, and lets you work with AWS queues in a similar way to the message-pump pattern used in the latest Azure SDK for Service Bus queues and topics. I’ve posted a simple wrapper class for subscribing to an SQS hub on gist here: A wrapper for the SQS client in the AWS SDK for.NET v2, which uses the message-pump pattern. Here’s the core functionality in the subscribe method: private async void Subscribe() { if (_isListening) { var request = new ReceiveMessageRequest { MaxNumberOfMessages = 10 }; request.QueueUrl = QueueUrl; var result = await _sqsClient.ReceiveMessageAsync(request, _cancellationTokenSource.Token); if (result.Messages.Count > 0) { foreach (var message in result.Messages) { if (_receiveAction != null && message != null) { _receiveAction(message.Body); DeleteMessage(message.ReceiptHandle); } } } } if (_isListening) { Subscribe(); } } which you call with something like this: client.Subscribe(x=>Log.Debug(x.Body)); The async SDK call returns when there is something in the queue, and will run your receive action for every message it gets in the batch (defaults to the maximum size of 10 messages per call). The listener will sit there awaiting messages until you stop it with: client.Unsubscribe(); Internally it has a cancellation token which it sets when you call unsubscribe, which cancels any in-flight call to SQS and stops the pump. The wrapper will also create the queue if it doesn’t exist at runtime. The Ensure() method gets called in the constructor so when you first use the client for a queue (sending or subscribing), it will set itself up: if (!Exists()) { var request = new CreateQueueRequest(); request.QueueName = QueueName; var response = _sqsClient.CreateQueue(request); QueueUrl = response.QueueUrl; } The Exists() check has to do make a call to ListQueues on the SNS client, as it doesn’t provide its own method to check if a queue exists. That call also populates the Amazon Resource Name, the unique identifier for this queue, which will be useful later. To use the wrapper, just instantiate and go: var queueClient = new QueueClient(“ProcessWorkflow”); queueClient.Subscribe(x=>Log.Debug(x.Body)); var message = {}; //etc. queueClient.Send(message);

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• Installing Ubuntu 12.04 on NUC intel i3 DC3217IYE

  - by Kieron

  System: NUC i3, 2 hdmi ports, ethernet, no wireless. UEFI boot 2x2gb ram 30gb mSATA internal drive Ubuntu 64bit 12.04.03 Hello i am having much trouble loading an OS on my NUC. I started out attempting another OS with various loaders (beast/hack) without much success,(various panics on boot or endless reboot loops, or graphics failures) after many tries i decided to attempt Ubuntu. Many years ago i loaded Ubuntu on an e-machine without an issue so i figured it would go smoothly, nothing could be further from the truth. The Live USB stick loads, but when i am installing the OS it always fails to load grub 2. Obviously it wont boot from SSD without grub2. I searched and found that Boot-repair should fix it...so i created a live usb with boot repair...it refuses to repair the grub because the install never finished and the needed partions are not fully created and flagged. It also demands an internet connection which i am unable to provide. I then ran gparted in an attempt to create the needed partitions manually, then re-ran boot repair turning off the "check internet" option. and disabling the re-install grub hoping it would create the missing directories and or fix the flags. it appeared to run successfully but upon return to the Ubuntu live USB it still fails at the grub2 install. also gparted doesnt have the same choices that Ubuntu install has when creating partitions, causing it to not recognize that i already had a root, or an EFI directory or it sometimes couldnt tell what the format of the partition was...all very annoying the reason i cant connect to internet (and cant upload the error logs) is the nuc only has Ethernet and the location i have to set up is too far away from modem. i can not move the monitor closer to modem as it is a 50inch LCD. I just want to do a basic install with one user acct and remote desktop (vnc) turned on so i can move the NUC to the modem connect via ethernet and then finish setting it up via Remote desktop/VNC chicken from my mac. While i await any assistance you maybe able to provide i am going to attempt to switch to the 32bit version and legacy boot to see if that can load grub. thnx again to anyone that can come up with a possible solution. i would love to hit "erase and install ubuntu" if anyone can figure out what is stopping that simple answer from working. Also disks (CD/DVD) are not an option as neither my Mac mini or my NUC have optical drives, and i have no desire to buy one for one task

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• Display Driver Issue on an hp TX2-1160ea Notebook

  - by Sam

  I'm new to Linux and recently switched to Ubuntu 11.04 due to my project requirement. My laptop has been freezing and going to black screen of death when I run anything related to display (Share desktop, stream video, etc). Today I went through the Ubuntu forum to install the appropriate graphic driver and, after doing it, I rebooted my PC. It gave an error before login saying "select the recovery mode" and after clicking OK, it didn't give the same error on reboot but I've lost the 11.04 graphical interface and all I see is the interface of Ubuntu v10 with slow visuals (even scrolling up/down on browser is really slow). For the reference, here's a desktop screenshot so that you can understand the situation. Also the laptop is overheating. How can I fix this problem? How can i get the Ubuntu 11.04 view back? I also tried Google, but couldn't find any issue like this. Some general Information: Laptop: HP TouchSmart TX2-1160ea Processor: AMD Turion TX2 Memory: 4GB OS: Ubuntu 11.04 Some debugging information:: $ report-hw | grep controller lspci -knn: 00:11.0 SATA controller [0106]: ATI Technologies Inc SB7x0/SB8x0/SB9x0 SATA Controller [AHCI mode] [1002:4391] lspci -knn: 00:14.3 ISA bridge [0601]: ATI Technologies Inc SB7x0/SB8x0/SB9x0 LPC host controller [1002:439d] lspci -knn: 01:05.0 VGA compatible controller [0300]: ATI Technologies Inc RS780M/RS780MN [Radeon HD 3200 Graphics] [1002:9612] lspci -knn: 08:00.0 Network controller [0280]: Broadcom Corporation BCM4322 802.11a/b/g/n Wireless LAN Controller [14e4:432b] (rev 01) lspci -knn: 09:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller [10ec:8168] (rev 02) And: $ dpkg -l '*fglrx*' Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) ||/ Name Version Description +++-==============-==============-============================================ ii fglrx 2:8.840-0ubunt Video driver for the ATI graphics accelerato ii fglrx-amdcccle 2:8.840-0ubunt Catalyst Control Center for the ATI graphics un fglrx-control <none> (no description available) un fglrx-control- <none> (no description available) ii fglrx-dev 2:8.840-0ubunt Video driver for the ATI graphics accelerato un fglrx-driver <none> (no description available) un fglrx-driver-d <none> (no description available) un fglrx-kernel-s <none> (no description available) un fglrx-modalias <none> (no description available) un xfree86-driver <none> (no description available) un xfree86-driver <none> (no description available) un xorg-driver-fg <none> (no description available) un xorg-driver-fg <none> (no description available) If you need any more information that could help, just ask.

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• Play a Webpage Display Prank in Google Chrome

  - by Asian Angel

  Are you looking for a fun but innocent prank to play on someone who loves using Google Chrome? If so then you may want to have a closer look at the Upside Down extension for Chrome. Before Here is our example webpage before starting the prank…looking all “normal like”. Upside Down in Action As soon as the extension has been installed you are ready to go. If you had a webpage open before installing the extension you will only need to refresh the page. As soon as the page has been refreshed or a new one is opened everything is going to look messed up very quickly. With the default setting there are five different “looks” available. To cycle through the five “looks” use the “Windows Key + Semicolon” or “Command + Semicolon” to toggle through them. On the sixth toggle the webpage will revert to normal (toggling afterwards starts the whole process again). Here are the five “looks” available…         Options There are options available for the extension where you can focus on just a specific effect or a group of effects. You can also enable a “Grayscale Effect” and even set a delay timer (a definite “evil touch”)! Think of the fun and surprised looks that await… Conclusion If you have been looking for a fun and unexpected prank for your favorite Google Chrome fan then this just might be what you have been looking for. Get ready to sit back and watch the fun. Links Download the Upside Down extension (Google Chrome Extensions) Similar Articles Productive Geek Tips Take Screenshots of Any Webpage in Google ChromeHow to Make Google Chrome Your Default BrowserSubscribe to RSS Feeds in Chrome with a Single ClickActivate the Redesigned New-Tab Interface in Google ChromeFriday Fun: Play MineSweeper in Google Chrome TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 If Web Browsers Were Modes of Transportation Google Translate (for animals) Out of 100 Tweeters Roadkill’s Scan Port scans for open ports Out of band Security Update for Internet Explorer 7 Cool Looking Screensavers for Windows

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• TechEd 2012: Windows 8 And Metro

  - by Tim Murphy

  Windows 8 is here (or at least very close) and that was the main feature of this morning’s key note.  Antoine LeBlond started off by apologizing to the IT professionals since he planned on showing code.  I’m not sure if IT Pros are that easily confused or why you would need such a disclaimer.  Developers do real work, IT Pros just play with toys (just kidding). The highlights of the Windows 8 keynote for me started with some of the UI design elements that I had not seen when I was shown one of the Build tablets.  Specifically I liked the AppBar features that we have become used to with Windows Phone and some of the gesture features.  Even though they have been available on other platforms before I think Microsoft really got them right. Two other great features of Windows 8 that they demonstrated were the Hyper-V capabilities and the ability to run Windows 8 anywhere from a USB key.  My jaw dropped through the floor seeing a feature rich OS boot off of a thumb drive. WOW!  I also can’t wait to get rid of dual booting just to run Hyper-V images when developing. The morning continued with a session on Metro XAML development with Tim Heuer.  While included a lot of great XAML Metro demos, I was pleasantly surprised by some of the things I found out about Visual Studio 2012.  Finding out that Blend is now integrated with VS2012 was a nice addition after working with them as separate applications was an encouraging start. Moving on to Metro he introduced the nugget that WinRT is Async everywhere.  How deep this model goes will be an interesting thing to find out as I learn more about developing for the platform.  Thankfully he followed that up with a couple of new keywords, await and async, that eliminates a lot of plumbing that has been required in the past for asynchronous transactions. Tim also related that since the Metro framework is relatively small and most apps will use a significant amount of it the entire surface is referenced by default.  This is a contrast to adding namespace and assemblies one after another as we normally do. This was such a power packed session that I can’t detail it all here so here is the teaser list. New icons in VS2012 for extension methods Emulator/simulator testing features for gestures Portable class libraries XAML no longer managed code And so much more …   del.icio.us Tags: Windows 8,Metro,Tim Heuer,XAML,Widows Phone,Hyper-V,Antoine LeBlond,TechEd,TechEd 2012,Visual Studio 2012,Visual Studio

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• High mysql server load, sar output

  - by eric

  I have a MySQL Server that should be performing better than it seems to be. We're running ubuntu on a Amazon Cluster Compute (cc1.4xlarge) Linux ip-10-0-1-60 3.2.0-25-virtual #40-Ubuntu SMP Wed May 23 22:20:17 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux Distributor ID: Ubuntu Description: Ubuntu 12.04 LTS Release: 12.04 Codename: precise I have several output files from sar that i'm not really sure how to interpret. For example, I ran: # Individual block device I/O activities sar -d 1 180 > logs/block_device_io.log & which gave me what looks like really high utilisation of my disk (turns out this block device maps to /dev/xvdh on /var/lib/mysql type ext4 (rw,_netdev) The output from my log: 10:48:59 PM DEV tps rd_sec/s wr_sec/s avgrq-sz avgqu-sz await svctm %util 10:49:00 PM dev202-16 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 10:49:00 PM dev202-32 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 10:49:00 PM dev8-0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 10:49:00 PM dev202-112 1008.00 31040.00 1416.00 32.20 1.02 1.01 0.89 90.00 10:49:00 PM dev202-80 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Am I wrong in thinking this is a problem? I have it above 90% almost the entire time we're seeing slowness. Or does this just mean MySQL is doing what it's supposed to do?

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• Is there any free software to check for issues with a DVD drive?

  - by AgentConundrum

  I don't usually play movies on my laptop (prefer the standalone with the tv), but I tried to watch one the other night, and noticed playback was really choppy and had audio artifacts in places. I thought it could be related to memory issues so I rebooted and tried again, but the results were the same. I considered that it could be an issue with the disc, so I tried to clean it but again there was no change. I don't think the problem is with the disc, because I tried another disc and it also had the same problem. I don't think I've ever watched the second disc since I've had it, so it should have been safe in its jewel case. Also, there were no issues when I watched an episode off the first disc in my standalone player. What I'm wondering is: are there are any (free) utilities that can check for issues with the drive itself? I looked around but most of the software I found focuses on integrity checks for the disc, not the drive. I have had issues with this laptop recently (had to replace the keyboard when the cat damaged it while I was cleaning dust out and the machine was ripped apart, also replaced part of the chassis after I cracked it when I tried to open it not knowing a screw was still in it) so I may have just replaced the drive incorrectly. I'm going to check on this while I await an answer to this question. Thanks.

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• ubuntu's average load never below "0.00 0.01 0.05"

  - by Karma Fusebox

  I have several ubuntu 12.04 VMs running on a ubuntu 12.04 KVM host. Those of the virtual machines that are totally idle with no services (except syslog and the other "small" standard stuff of a fresh installation) show a constant load of "0.00 0.01 0.05" in top/htop as average 1/5/15. When there are "real" applications running, the load averages behave perfectly normal but they never fall below the mentioned values. While this doesn't affect performance at all and could easily be ignored, it screws up the monitoring graphs in a very annoying way: (Notice how load15 behaves nicely if 0.05 for a short time in the right half of the pic) Unfortunately I don't know what diagnostic outputs might be helpful for you, so here's some default stuff: # top top - 16:31:01 up 1:05, 1 user, load average: 0.00, 0.01, 0.05 Tasks: 62 total, 1 running, 61 sleeping, 0 stopped, 0 zombie Cpu(s): 0.2%us, 0.2%sy, 0.0%ni, 99.2%id, 0.5%wa, 0.0%hi, 0.0%si, 0.0%st Mem: 1019464k total, 73452k used, 946012k free, 6140k buffers Swap: 0k total, 0k used, 0k free, 22504k cached . # free -m total used free shared buffers cached Mem: 995 72 923 0 6 21 -/+ buffers/cache: 43 951 Swap: 0 0 0 . # iostat -x /dev/vda Linux 3.2.0-32-virtual (vm3) 11/15/2012 _x86_64_ (2 CPU) avg-cpu: %user %nice %system %iowait %steal %idle 0.25 0.00 0.65 0.20 0.24 98.66 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util vda 0.14 0.12 0.51 0.22 6.74 1.46 22.50 0.02 23.26 20.64 29.30 7.63 0.56 Need something else? Has anyone ever seen this behavior? Might this be a bug in kvm/ubuntu/kernel 3.x in the end? Thanks a lot!

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• How to fix Windows 7 device removal notification loop

  - by Barry Kelly

  Bit of an odd one this. One of our PCs is getting caught in a loop some time after being turned on, usually after a USB storage device has been attached - sometimes an iPod, sometimes a GPS. Specifically, Windows Explorer starts showing a drive icon and letter (E:, as of right now) for the System partition (the small hidden one at the start of the boot drive). Then, the icon disappears. Then it reappears again. And disappears. It does this very quickly, at what looks like maybe 50 times a second. CPU usage in this loop is also very high; averages about 66%. This machine has an i7 920 CPU, which is quad core with hyperthreading; so this usage rate works out to about 5 100% busy threads, along with whatever normal idle load is (particularly Task Manager itself). Inspecting with Process Explorer shows that the device removal notification infrastructure has gone berserk. The threads in system service processes (i.e. apart from Windows Explorer) which are using all the CPU power relate to device notification. The Disk Management MMC snap-in also fails to run when the loop starts. The only way to break the loop, it seems, is to reboot the machine. Anyone seen anything similar to this, and know of a way to fix it? Machine details: Windows 7 x64, fully patched i7 920, 12GB RAM Intel SSD 80GB (X25-M, I believe; not G2) 2TB 5.2K disk for bulk storage AMD HD 5870 Further hardware details await. I'm going to go through and update all drivers I can find.

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• Red Gate Coder interviews: Alex Davies

  - by Michael Williamson

  Alex Davies has been a software engineer at Red Gate since graduating from university, and is currently busy working on .NET Demon. We talked about tackling parallel programming with his actors framework, a scientific approach to debugging, and how JavaScript is going to affect the programming languages we use in years to come. So, if we start at the start, how did you get started in programming? When I was seven or eight, I was given a BBC Micro for Christmas. I had asked for a Game Boy, but my dad thought it would be better to give me a proper computer. For a year or so, I only played games on it, but then I found the user guide for writing programs in it. I gradually started doing more stuff on it and found it fun. I liked creating. As I went into senior school I continued to write stuff on there, trying to write games that weren’t very good. I got a real computer when I was fourteen and found ways to write BASIC on it. Visual Basic to start with, and then something more interesting than that. How did you learn to program? Was there someone helping you out? Absolutely not! I learnt out of a book, or by experimenting. I remember the first time I found a loop, I was like “Oh my God! I don’t have to write out the same line over and over and over again any more. It’s amazing!” When did you think this might be something that you actually wanted to do as a career? For a long time, I thought it wasn’t something that you would do as a career, because it was too much fun to be a career. I thought I’d do chemistry at university and some kind of career based on chemical engineering. And then I went to a careers fair at school when I was seventeen or eighteen, and it just didn’t interest me whatsoever. I thought “I could be a programmer, and there’s loads of money there, and I’m good at it, and it’s fun”, but also that I shouldn’t spoil my hobby. Now I don’t really program in my spare time any more, which is a bit of a shame, but I program all the rest of the time, so I can live with it. Do you think you learnt much about programming at university? Yes, definitely! I went into university knowing how to make computers do anything I wanted them to do. However, I didn’t have the language to talk about algorithms, so the algorithms course in my first year was massively important. Learning other language paradigms like functional programming was really good for breadth of understanding. Functional programming influences normal programming through design rather than actually using it all the time. I draw inspiration from it to write imperative programs which I think is actually becoming really fashionable now, but I’ve been doing it for ages. I did it first! There were also some courses on really odd programming languages, a bit of Prolog, a little bit of C. Having a little bit of each of those is something that I would have never done on my own, so it was important. And then there are knowledge-based courses which are about not programming itself but things that have been programmed like TCP. Those are really important for examples for how to approach things. Did you do any internships while you were at university? Yeah, I spent both of my summers at the same company. I thought I could code well before I went there. Looking back at the crap that I produced, it was only surpassed in its crappiness by all of the other code already in that company. I’m so much better at writing nice code now than I used to be back then. Was there just not a culture of looking after your code? There was, they just didn’t hire people for their abilities in that area. They hired people for raw IQ. The first indicator of it going wrong was that they didn’t have any computer scientists, which is a bit odd in a programming company. But even beyond that they didn’t have people who learnt architecture from anyone else. Most of them had started straight out of university, so never really had experience or mentors to learn from. There wasn’t the experience to draw from to teach each other. In the second half of my second internship, I was being given tasks like looking at new technologies and teaching people stuff. Interns shouldn’t be teaching people how to do their jobs! All interns are going to have little nuggets of things that you don’t know about, but they shouldn’t consistently be the ones who know the most. It’s not a good environment to learn. I was going to ask how you found working with people who were more experienced than you… When I reached Red Gate, I found some people who were more experienced programmers than me, and that was difficult. I’ve been coding since I was tiny. At university there were people who were cleverer than me, but there weren’t very many who were more experienced programmers than me. During my internship, I didn’t find anyone who I classed as being a noticeably more experienced programmer than me. So, it was a shock to the system to have valid criticisms rather than just formatting criticisms. However, Red Gate’s not so big on the actual code review, at least it wasn’t when I started. We did an entire product release and then somebody looked over all of the UI of that product which I’d written and say what they didn’t like. By that point, it was way too late and I’d disagree with them. Do you think the lack of code reviews was a bad thing? I think if there’s going to be any oversight of new people, then it should be continuous rather than chunky. For me I don’t mind too much, I could go out and get oversight if I wanted it, and in those situations I felt comfortable without it. If I was managing the new person, then maybe I’d be keener on oversight and then the right way to do it is continuously and in very, very small chunks. Have you had any significant projects you’ve worked on outside of a job? When I was a teenager I wrote all sorts of stuff. I used to write games, I derived how to do isomorphic projections myself once. I didn’t know what the word was so I couldn’t Google for it, so I worked it out myself. It was horrifically complicated. But it sort of tailed off when I started at university, and is now basically zero. If I do side-projects now, they tend to be work-related side projects like my actors framework, NAct, which I started in a down tools week. Could you explain a little more about NAct? It is a little C# framework for writing parallel code more easily. Parallel programming is difficult when you need to write to shared data. Sometimes parallel programming is easy because you don’t need to write to shared data. When you do need to access shared data, you could just have your threads pile in and do their work, but then you would screw up the data because the threads would trample on each other’s toes. You could lock, but locks are really dangerous if you’re using more than one of them. You get interactions like deadlocks, and that’s just nasty. Actors instead allows you to say this piece of data belongs to this thread of execution, and nobody else can read it. If you want to read it, then ask that thread of execution for a piece of it by sending a message, and it will send the data back by a message. And that avoids deadlocks as long as you follow some obvious rules about not making your actors sit around waiting for other actors to do something. There are lots of ways to write actors, NAct allows you to do it as if it was method calls on other objects, which means you get all the strong type-safety that C# programmers like. Do you think that this is suitable for the majority of parallel programming, or do you think it’s only suitable for specific cases? It’s suitable for most difficult parallel programming. If you’ve just got a hundred web requests which are all independent of each other, then I wouldn’t bother because it’s easier to just spin them up in separate threads and they can proceed independently of each other. But where you’ve got difficult parallel programming, where you’ve got multiple threads accessing multiple bits of data in multiple ways at different times, then actors is at least as good as all other ways, and is, I reckon, easier to think about. When you’re using actors, you presumably still have to write your code in a different way from you would otherwise using single-threaded code. You can’t use actors with any methods that have return types, because you’re not allowed to call into another actor and wait for it. If you want to get a piece of data out of another actor, then you’ve got to use tasks so that you can use “async” and “await” to await asynchronously for it. But other than that, you can still stick things in classes so it’s not too different really. Rather than having thousands of objects with mutable state, you can use component-orientated design, where there are only a few mutable classes which each have a small number of instances. Then there can be thousands of immutable objects. If you tend to do that anyway, then actors isn’t much of a jump. If I’ve already built my system without any parallelism, how hard is it to add actors to exploit all eight cores on my desktop? Usually pretty easy. If you can identify even one boundary where things look like messages and you have components where some objects live on one side and these other objects live on the other side, then you can have a granddaddy object on one side be an actor and it will parallelise as it goes across that boundary. Not too difficult. If we do get 1000-core desktop PCs, do you think actors will scale up? It’s hard. There are always in the order of twenty to fifty actors in my whole program because I tend to write each component as actors, and I tend to have one instance of each component. So this won’t scale to a thousand cores. What you can do is write data structures out of actors. I use dictionaries all over the place, and if you need a dictionary that is going to be accessed concurrently, then you could build one of those out of actors in no time. You can use queuing to marshal requests between different slices of the dictionary which are living on different threads. So it’s like a distributed hash table but all of the chunks of it are on the same machine. That means that each of these thousand processors has cached one small piece of the dictionary. I reckon it wouldn’t be too big a leap to start doing proper parallelism. Do you think it helps if actors get baked into the language, similarly to Erlang? Erlang is excellent in that it has thread-local garbage collection. C# doesn’t, so there’s a limit to how well C# actors can possibly scale because there’s a single garbage collected heap shared between all of them. When you do a global garbage collection, you’ve got to stop all of the actors, which is seriously expensive, whereas in Erlang garbage collections happen per-actor, so they’re insanely cheap. However, Erlang deviated from all the sensible language design that people have used recently and has just come up with crazy stuff. You can definitely retrofit thread-local garbage collection to .NET, and then it’s quite well-suited to support actors, even if it’s not baked into the language. Speaking of language design, do you have a favourite programming language? I’ll choose a language which I’ve never written before. I like the idea of Scala. It sounds like C#, only with some of the niggles gone. I enjoy writing static types. It means you don’t have to writing tests so much. When you say it doesn’t have some of the niggles? C# doesn’t allow the use of a property as a method group. It doesn’t have Scala case classes, or sum types, where you can do a switch statement and the compiler checks that you’ve checked all the cases, which is really useful in functional-style programming. Pattern-matching, in other words. That’s actually the major niggle. C# is pretty good, and I’m quite happy with C#. And what about going even further with the type system to remove the need for tests to something like Haskell? Or is that a step too far? I’m quite a pragmatist, I don’t think I could deal with trying to write big systems in languages with too few other users, especially when learning how to structure things. I just don’t know anyone who can teach me, and the Internet won’t teach me. That’s the main reason I wouldn’t use it. If I turned up at a company that writes big systems in Haskell, I would have no objection to that, but I wouldn’t instigate it. What about things in C#? For instance, there’s contracts in C#, so you can try to statically verify a bit more about your code. Do you think that’s useful, or just not worthwhile? I’ve not really tried it. My hunch is that it needs to be built into the language and be quite mathematical for it to work in real life, and that doesn’t seem to have ended up true for C# contracts. I don’t think anyone who’s tried them thinks they’re any good. I might be wrong. On a slightly different note, how do you like to debug code? I think I’m quite an odd debugger. I use guesswork extremely rarely, especially if something seems quite difficult to debug. I’ve been bitten spending hours and hours on guesswork and not being scientific about debugging in the past, so now I’m scientific to a fault. What I want is to see the bug happening in the debugger, to step through the bug happening. To watch the program going from a valid state to an invalid state. When there’s a bug and I can’t work out why it’s happening, I try to find some piece of evidence which places the bug in one section of the code. From that experiment, I binary chop on the possible causes of the bug. I suppose that means binary chopping on places in the code, or binary chopping on a stage through a processing cycle. Basically, I’m very stupid about how I debug. I won’t make any guesses, I won’t use any intuition, I will only identify the experiment that’s going to binary chop most effectively and repeat rather than trying to guess anything. I suppose it’s quite top-down. Is most of the time then spent in the debugger? Absolutely, if at all possible I will never debug using print statements or logs. I don’t really hold much stock in outputting logs. If there’s any bug which can be reproduced locally, I’d rather do it in the debugger than outputting logs. And with SmartAssembly error reporting, there’s not a lot that can’t be either observed in an error report and just fixed, or reproduced locally. And in those other situations, maybe I’ll use logs. But I hate using logs. You stare at the log, trying to guess what’s going on, and that’s exactly what I don’t like doing. You have to just look at it and see does this look right or wrong. We’ve covered how you get to grip with bugs. How do you get to grips with an entire codebase? I watch it in the debugger. I find little bugs and then try to fix them, and mostly do it by watching them in the debugger and gradually getting an understanding of how the code works using my process of binary chopping. I have to do a lot of reading and watching code to choose where my slicing-in-half experiment is going to be. The last time I did it was SmartAssembly. The old code was a complete mess, but at least it did things top to bottom. There wasn’t too much of some of the big abstractions where flow of control goes all over the place, into a base class and back again. Code’s really hard to understand when that happens. So I like to choose a little bug and try to fix it, and choose a bigger bug and try to fix it. Definitely learn by doing. I want to always have an aim so that I get a little achievement after every few hours of debugging. Once I’ve learnt the codebase I might be able to fix all the bugs in an hour, but I’d rather be using them as an aim while I’m learning the codebase. If I was a maintainer of a codebase, what should I do to make it as easy as possible for you to understand? Keep distinct concepts in different places. And name your stuff so that it’s obvious which concepts live there. You shouldn’t have some variable that gets set miles up the top of somewhere, and then is read miles down to choose some later behaviour. I’m talking from a very much SmartAssembly point of view because the old SmartAssembly codebase had tons and tons of these things, where it would read some property of the code and then deal with it later. Just thousands of variables in scope. Loads of things to think about. If you can keep concepts separate, then it aids me in my process of fixing bugs one at a time, because each bug is going to more or less be understandable in the one place where it is. And what about tests? Do you think they help at all? I’ve never had the opportunity to learn a codebase which has had tests, I don’t know what it’s like! What about when you’re actually developing? How useful do you find tests in finding bugs or regressions? Finding regressions, absolutely. Running bits of code that would be quite hard to run otherwise, definitely. It doesn’t happen very often that a test finds a bug in the first place. I don’t really buy nebulous promises like tests being a good way to think about the spec of the code. My thinking goes something like “This code works at the moment, great, ship it! Ah, there’s a way that this code doesn’t work. Okay, write a test, demonstrate that it doesn’t work, fix it, use the test to demonstrate that it’s now fixed, and keep the test for future regressions.” The most valuable tests are for bugs that have actually happened at some point, because bugs that have actually happened at some point, despite the fact that you think you’ve fixed them, are way more likely to appear again than new bugs are. Does that mean that when you write your code the first time, there are no tests? Often. The chance of there being a bug in a new feature is relatively unaffected by whether I’ve written a test for that new feature because I’m not good enough at writing tests to think of bugs that I would have written into the code. So not writing regression tests for all of your code hasn’t affected you too badly? There are different kinds of features. Some of them just always work, and are just not flaky, they just continue working whatever you throw at them. Maybe because the type-checker is particularly effective around them. Writing tests for those features which just tend to always work is a waste of time. And because it’s a waste of time I’ll tend to wait until a feature has demonstrated its flakiness by having bugs in it before I start trying to test it. You can get a feel for whether it’s going to be flaky code as you’re writing it. I try to write it to make it not flaky, but there are some things that are just inherently flaky. And very occasionally, I’ll think “this is going to be flaky” as I’m writing, and then maybe do a test, but not most of the time. How do you think your programming style has changed over time? I’ve got clearer about what the right way of doing things is. I used to flip-flop a lot between different ideas. Five years ago I came up with some really good ideas and some really terrible ideas. All of them seemed great when I thought of them, but they were quite diverse ideas, whereas now I have a smaller set of reliable ideas that are actually good for structuring code. So my code is probably more similar to itself than it used to be back in the day, when I was trying stuff out. I’ve got more disciplined about encapsulation, I think. There are operational things like I use actors more now than I used to, and that forces me to use immutability more than I used to. The first code that I wrote in Red Gate was the memory profiler UI, and that was an actor, I just didn’t know the name of it at the time. I don’t really use object-orientation. By object-orientation, I mean having n objects of the same type which are mutable. I want a constant number of objects that are mutable, and they should be different types. I stick stuff in dictionaries and then have one thing that owns the dictionary and puts stuff in and out of it. That’s definitely a pattern that I’ve seen recently. I think maybe I’m doing functional programming. Possibly. It’s plausible. If you had to summarise the essence of programming in a pithy sentence, how would you do it? Programming is the form of art that, without losing any of the beauty of architecture or fine art, allows you to produce things that people love and you make money from. So you think it’s an art rather than a science? It’s a little bit of engineering, a smidgeon of maths, but it’s not science. Like architecture, programming is on that boundary between art and engineering. If you want to do it really nicely, it’s mostly art. You can get away with doing architecture and programming entirely by having a good engineering mind, but you’re not going to produce anything nice. You’re not going to have joy doing it if you’re an engineering mind. Architects who are just engineering minds are not going to enjoy their job. I suppose engineering is the foundation on which you build the art. Exactly. How do you think programming is going to change over the next ten years? There will be an unfortunate shift towards dynamically-typed languages, because of JavaScript. JavaScript has an unfair advantage. JavaScript’s unfair advantage will cause more people to be exposed to dynamically-typed languages, which means other dynamically-typed languages crop up and the best features go into dynamically-typed languages. Then people conflate the good features with the fact that it’s dynamically-typed, and more investment goes into dynamically-typed languages. They end up better, so people use them. What about the idea of compiling other languages, possibly statically-typed, to JavaScript? It’s a reasonable idea. I would like to do it, but I don’t think enough people in the world are going to do it to make it pick up. The hordes of beginners are the lifeblood of a language community. They are what makes there be good tools and what makes there be vibrant community websites. And any particular thing which is the same as JavaScript only with extra stuff added to it, although it might be technically great, is not going to have the hordes of beginners. JavaScript is always to be quickest and easiest way for a beginner to start programming in the browser. And dynamically-typed languages are great for beginners. Compilers are pretty scary and beginners don’t write big code. And having your errors come up in the same place, whether they’re statically checkable errors or not, is quite nice for a beginner. If someone asked me to teach them some programming, I’d teach them JavaScript. If dynamically-typed languages are great for beginners, when do you think the benefits of static typing start to kick in? The value of having a statically typed program is in the tools that rely on the static types to produce a smooth IDE experience rather than actually telling me my compile errors. And only once you’re experienced enough a programmer that having a really smooth IDE experience makes a blind bit of difference, does static typing make a blind bit of difference. So it’s not really about size of codebase. If I go and write up a tiny program, I’m still going to get value out of writing it in C# using ReSharper because I’m experienced with C# and ReSharper enough to be able to write code five times faster if I have that help. Any other visions of the future? Nobody’s going to use actors. Because everyone’s going to be running on single-core VMs connected over network-ready protocols like JSON over HTTP. So, parallelism within one operating system is going to die. But until then, you should use actors. More Red Gater Coder interviews

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• SQLAuthority News – Speaking Sessions at TechEd India – 3 Sessions – 1 Panel Discussion

  - by pinaldave

  Microsoft Tech-Ed India 2010 is considered as the major Technology event of the year for various IT professionals and developers. This event will feature a comprehensive forum in order   to learn, connect, explore, and evolve the current technologies we have today. I would recommend this event to you since here you will learn about today’s cutting-edge trends, thereby enhancing your work profile and getting ahead of the rest. But, the most important benefit of all might be the networking opportunity that that you can attain by attending the forum. You can build personal connections with various Microsoft experts and peers that will last even far beyond this event! It also feels good to let you know that I will be speaking at this year’s event! So, here are the sessions that await you in this mega-forum. Session 1: True Lies of SQL Server – SQL Myth Buster Date: April 12, 2010  Time: 11:15pm – 11:45pm In this 30-minute demo session, I am going to briefly demonstrate few SQL Server Myth and their resolution backing up with some demo. This demo session is a must-attend for all developers and administrators who would come to the event. This is going to be a very quick yet  fun session. Session 2: Master Data Services in Microsoft SQL Server 2008 R2 Date: April 12, 2010  Time: 2:30pm-3:30pm SQL Server Master Data Services will ship with SQL Server 2008 R2 and will improve Microsoft’s platform appeal. This session provides an in depth demonstration of MDS features and highlights important usage scenarios. Master Data Services enables consistent decision making by allowing you to create, manage and propagate changes from single master view of your business entities. Also with MDS – Master Data-hub which is the vital component helps ensure reporting consistency across systems and deliver faster more accurate results across the enterprise. We will talk about establishing the basis for a centralized approach to defining, deploying, and managing master data in the enterprise. Session 3: Developing with SQL Server Spatial and Deep Dive into Spatial Indexing Date: April 14, 2010 Time: 5:00pm-6:00pm Microsoft SQL Server 2008 delivers new spatial data types that enable you to consume, use, and extend location-based data through spatial-enabled applications. Attend this session to learn how to use spatial functionality in next version of SQL Server to build and optimize spatial queries. This session outlines the new geography data type to store geodetic spatial data and perform operations on it, use the new geometry data type to store planar spatial data and perform operations on it, take advantage of new spatial indexes for high performance queries, use the new spatial results tab to quickly and easily view spatial query results directly from within Management Studio, extend spatial data capabilities by building or integrating location-enabled applications through support for spatial standards and specifications and much more. Panel Discussion: Harness the power of Web – SEO and Technical Blogging Date: April 12, 2010 Time: 5:00pm-6:00pm Here you will learn lots of tricks and tips about SEO and Technical Blogging from various Industry Technical Blogging Experts. This event will surely be one of the most important Tech conventions of 2010. TechEd is going to be a very busy time for Tech developers and enthusiasts, since every evening there will be a fun session to attend. If you are interested in any of the above topics for every session, I suggest that you visit each of them as you will learn so many things about the topic to be discussed. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: MVP, Pinal Dave, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Author Visit, SQLAuthority News, T SQL, Technology Tagged: TechEd, TechEdIn

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• Welcome 2011

  - by WeigeltRo

  Things that happened in 2010 MIX10 was absolutely fantastic. Read my report of MIX10 to see why.   The dotnet Cologne 2010, the community conference organized by the .NET user group Köln and my own group Bonn-to-Code.Net became an even bigger success than I dared to dream of.   There was a huge discrepancy between the efforts by Microsoft to support .NET user groups to organize public live streaming events of the PDC keynote (the dotnet Cologne team joined forces with netug  Niederrhein to organize the PDCologne) and the actual content of the keynote. The reaction of the audience at our event was “meh” and even worse I seriously doubt we’ll ever get that number of people to such an event (which on top of that suffered from technical difficulties beyond our control).   What definitely would have deserved the public live streaming event treatment was the Silverlight Firestarter (aka “Silverlight Damage Control”) event. And maybe we would have thought about organizing something if it weren’t for the “burned earth” left by the PDC keynote. Anyway, the stuff shown at the firestarter keynote was the topic of conversations among colleagues days later (“did you see that? oh yeah, that was seriously cool”). Things that I have learned/observed/noticed in 2010 In the long run, there’s a huge difference between “It works pretty well” and “it just works and I never have to think about it”. I had to get rid of my USB graphics adapter powering the third monitor (read about it in this blog post). Various small issues (desktop icons sometimes moving their positions after a reboot for no apparent reasons, at least one game I couldn’t get run at all, all three monitors sometimes simply refusing to wake up after standby) finally made me buy a PCIe 1x graphics adapter. If you’re interested: The combination of a NVIDIA GTX 460 and a GT 220 is running in “don’t make me think” mode for a couple of months now.   PowerPoint 2010 is a seriously cool piece of software. Not only the new hardware-accelerated effects, but also features like built-in background removal and picture processing (which in many cases are simply “good enough” and save a lot of time) or the smart guides.   Outlook 2010 crashes on me a lot. I haven’t been successful in reproducing these crashes, they just happen when every couple of days on different occasions (only thing in common: I clicked something in the main window – yeah, very helpful observation)   Visual Studio 2010 reminds me of Visual Studio 2005 before SP1, which is actually not a good thing to say about a piece of software. I think it’s telling that Microsoft’s message regarding the beta of SP1 has been different from earlier service pack betas (promising an upgrade path for a beta to the RTM sounds to me like “please, please use it NOW!”).   I have a love/hate relationship with ReSharper. I don’t want to develop without it, but at the same time I can’t fail to notice that ReSharper is taking a heavy toll in terms of performance and sometimes stability. Things I’m looking forward to in 2011 Obviously, the dotnet Cologne 2011. We already have been able to score some big name sponsors (Microsoft, Intel), but we’re still looking for more sponsors. And be assured that we’ll make sure that our partners get the most out of their contribution, regardless of how big or small.   MIX11, period.    Silverlight 5 is going to be great. The only thing I’m a bit nervous about is that I still haven’t read anything official on whether C# next version’s async/await will be in it. Leaving that out would be really stupid considering the end-of-2011 release of SL5 (moving the next release way into the future).

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• Spotlight on an office - Denmark

  - by jessica.ebbelaar(at)oracle.com

  Hi, my name is Michael. I work as an Intern at the Danish office in Ballerup. My job is a part-time position beside my bachelor study in International Business at Copenhagen Business School. I joined Oracle end of February last year, and what a thrilling ride it has been! Last year, when I was offered the position, there was no doubt that I wanted to go for it. Back then, I only had little idea about Oracle as a company and what kind of exciting assignments lay ahead of me. My main role is internal communications, i.e. editor of a monthly employee’s news letter; Newszone. It is an interesting task, since it requires that I am updated on the different activities that take place within the Oracle Denmark office. I try to bring interesting articles, which are relevant and interesting news to my colleagues and it allows me to interact with many different persons at the office and to learn from their experience, which give me great inspiration and ideas for the magazine. Besides being the editor of Newszone, I also make sure that other communication flow freely at the Oracle Denmark office. I do this through our LCD screen channels. I update the internal channel with the latest information and important messages for employees, and on the external channel I circulate marketing videos featuring Oracle products and customer reference stories. In addition to this, I have the responsibility acting as a content manager of the Local Communication Denmark site on MyOracle (UCM). These are more or less my usual work assignments. On top of these I take care of various ad hoc assignments such as updating the GCM database, renew newspaper subscriptions etc. The Oracle Denmark office Being part of the local employees club I also assist with arranging social events outside working hours – e.g. evenings at the theater or cinema or by attending many of the sportsactivities;such as our running club, cycling club, food club and book club. These activities have indeed helped me grow my personal network within Oracle.  The office is packed with engaging, high-paced and motivated people who manage to take time off to spend a day attending Corporate Social Responsibility initiatives, one of them being GVD (Global Volunteer Day) with approximately 40 employees attending. This proofs some of the social responsible aspects of Oracle. I was positively surprised on how the office (named O-Zone) is designed. The office is designed into three distinct zones, namely Call zone, Project and Dialogue zone and Quiet zone, having different working environments for different job roles. The other thing which I like is that you do not have your own desk, which means you get to sit next to different people every day, getting new ideas and inspiration as well as getting to know more people in the organization you work in. To sum up: If you are considering pursuing an intern or a career after graduation in Oracle, do it! You will not regret it. It has given me many relevant practical experiences beside my study, and I am sure many great experiences will await you too.   Want to know more about the current vacancies in Denmark? Check http://campus.oracle.com for all of our vacancies.

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• iPhone SQLite Password Field Encryption

  - by Louis Russell

  Good Afternoon Guys and Girls, Hopefully this will be a quick and easy question. I am building an App that requires the user to input their login details for an online service that it links to. Multiple login details can be added and saved as the user may have several accounts that they would like to switch between. These details will be stored in an SQLite database and will contain their passwords. Now the questions are: 1: Should these passwords be encrypted in the database? My instinct would say yes but then I do not know how secure the device and system is and if this is necessary. 2: If they should be encrypted what should I use? I think encrypting the whole database file sounds a bit over-kill so should I just encrypt the password before saving it to the database? If this is case what could I use to achieve this? I have found reference to a "crypt(3)" but am having trouble finding much about it or how to implement it. I eagerly await your replies!

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• Weblogic 10.3.0 : Loosing a stateless session bean in the bean pool

  - by KlasE

  Hi, We have a strange situation where we loose a Stateless SessionBean in a Bean Pool in Weblogic 10.3.0 Since we only have one bean in the pool, this effectively hangs all incoming calls. We do not want more than one instance in the pool because of application restrictions. In the Weblogic admin console, we can see that there are 1 instance in the bean pool, 0 beans in use and 1 waiting incoming request. The question is, what can have caused the system to not send the request to the one obviously free bean instance? This happens after several hours and over 100000 incoming requests, and the same scenario worked fine in the old weblogic 8 environment. We get the following stacktrace: "[ACTIVE] ExecuteThread: '5' for queue: 'weblogic.kernel.Default (self-tuning)'" waiting for lock java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject@b0d484 TIMED_WAITING sun.misc.Unsafe.park(Native Method) java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:198) java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2054) weblogic.ejb.container.pool.StatelessSessionPool.waitForBean(StatelessSessionPool.java:269) weblogic.ejb.container.pool.StatelessSessionPool.getBean(StatelessSessionPool.java:111) weblogic.ejb.container.manager.StatelessManager.preInvoke(StatelessManager.java:148) weblogic.ejb.container.internal.BaseRemoteObject.preInvoke(BaseRemoteObject.java:227) weblogic.ejb.container.internal.StatelessRemoteObject.preInvoke(StatelessRemoteObject.java:52) com.mycompany.beans.MessageLogFacace_n73y0z_EOImpl.isMyStuffValid(MessageLogFacace_n73y0z_EOImpl.java:261) com.mycompany.beans.MessageLogFacace_n73y0z_EOImpl_WLSkel.invoke(Unknown Source) weblogic.rmi.internal.BasicServerRef.invoke(BasicServerRef.java:589) weblogic.rmi.cluster.ClusterableServerRef.invoke(ClusterableServerRef.java:230) weblogic.rmi.internal.BasicServerRef$1.run(BasicServerRef.java:477) weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:363) weblogic.security.service.SecurityManager.runAs(Unknown Source) weblogic.rmi.internal.BasicServerRef.handleRequest(BasicServerRef.java:473) weblogic.rmi.internal.wls.WLSExecuteRequest.run(WLSExecuteRequest.java:118) weblogic.work.ExecuteThread.execute(ExecuteThread.java:201) weblogic.work.ExecuteThread.run(ExecuteThread.java:173) Any help would be very welcome. Regards Klas

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• So can unique_ptr be used safely in stl collections?

  - by DanDan

  I am confused with unique_ptr and rvalue move philosophy. Let's say we have two collections: std::vector<std::auto_ptr<int>> autoCollection; std::vector<std::unique_ptr<int>> uniqueCollection; Now I would expect the following to fail, as there is no telling what the algorithm is doing internally and maybe making internal pivot copies and the like, thus ripping away ownership from the auto_ptr: std::sort(autoCollection.begin(), autoCollection.end()); I get this. And the compiler rightly disallows this happening. But then I do this: std::sort(uniqueCollection.begin(), uniqueCollection.end()); And this compiles. And I do not understand why. I did not think unique_ptrs could be copied. Does this mean a pivot value cannot be taken, so the sort is less efficient? Or is this pivot actually a move, which in fact is as dangerous as the collection of auto_ptrs, and should be disallowed by the compiler? I think I am missing some crucial piece of information, so I eagerly await someone to supply me with the aha! moment.

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