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• Defragging Host OS of VMWare

  - by JackLocke

  Hi All, I want to ask something that has been puzzling me from last few days. I will try to explain my problem as clear as I can ... I have VMWare Workstation installed in my machine. And I use one separate 100Gb drive which stores all of my virtual machines, nothing else. Now, last week I was playing with a De-fragmentation tool called "Smart Defrag" which showed me in its analysis report that my drive where I am currently storing all of my Virtual Machines has more than 80% of fragmentation !!! Now my question is ... What will be the effect on my Guest / VM machine performance if I defrag my Host machine ... I mean this Host machine is essentially storing those virtual machines, but still dont have any direct access to what ever is stored in those machines ... so defraging the host should not cause any problem. But before proceeding, I want to hear from other people who may have met same problem. I will really appreciate any help ... BTW, I am using Windows 7 as Host and the guest machines I am using are Windows 2008 & 2003 & Ubuntu 10.04 THanks, Jack

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• External Storage for 2TB of backups and 4TB of data RAID level? HW vs Software?

  - by Jerry Mayers

  I have a Mac Mini set up as a media center/file server. Currently I just have a hodgepodge mess of external drives for storage. I'm maxed out, and I have some new laptops on the way with much larger drives and I need to work out a good storage solution for backing them up, as well as storing media on the server. I need around 2 TB of storage for the time machine backups from my various systems and around 2 TB more for media. I would like to build this to handle around 6 TB total so I have some growing room. Since I'm using a Mac Mini as the server I need to use external enclosure(s) that support USB 2 or Firewire 800 (preferred) or gigabit Ethernet. Performance of the system isn't a huge concern since the majority of the access from other computers is done over 802.11N. I plan on using 2TB drives, for the final version, but initially I'll try and use my existing 2 (1TB) drives + some new 2TB drives, and swap the 1TB ones out as I fill up. As to the actual questions: Should I use hardware RAID in some enclosure? Because if the enclosure dies I have to find an identical one to get to my data right? Wouldn't a software RAID be better as I can use any method of connecting the drives to the system? Remember OS X server is my OS. What if I had to reinstall OS X, can I restore the software RAID easily? What RAID version should I use? For the 2TB used for the time machine disk I don't see why I need RAID here, just a single 2TB drive since its already the backup, but for the remaining 4TB it would be the only copy of the data so I should build some redundancy. I had a RAID 5 setup using a cheep RAID PCI card years ago running RAID 5 in a 2 TB array and when a drive died it wanted 48 hours to rebuild. Is this crazy slow for a setup of this size or is this to be expected? Any suggestions as to drive enclosures?

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• RAID 10 or RAID 5 for multiple VMs - what is the best choice?

  - by Lars Fastrup

  I have just ordered a new rig for my business. We do a lot of software development for Microsoft SharePoint and need the rig to run several virtual machines for development and test purposes. We will be using the free VMware ESXi for virtualization. For a start, we plan to build and start the following VMs - all with Windows Server 2008 R2 x64: Active Directory server MS SQL Server 2008 R2 Automated Build Server SharePoint 2010 Server for hosting our public Web site and our internal Intranet for a few people. The load on this server is going to be quite insignificant. 2xSharePoint 2007 development server 2xSharePoint 2010 development server Beyond that we will need to build several SharePoint farms for testing purposes. These VMs will only be started when needed. The specs of the new rig is: Dell R610 rack server 2xIntel XEON E5620 48GB RAM 6x146GB SAS drives Dell H700 RAID controller We believe the new server is going to make our VMs perform a lot better than our existing setup (2xIntel XEON, 16GB RAM, 2x500 GB SATA in RAID 1). But we are not sure about the RAID level for the new rig. Should we go for having the the 6x146GB SAS drives in a RAID 10 configuration or a RAID 5 configuration? RAID 10 seems to offer better write performance and lower risk of a RAID failure. But it comes at a cost of less drive space. Do we need RAID 10 or would RAID 5 also be a good choice for us?

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• Move EFI System Partition to another drive

  - by Pincopallino

  I had a Windows 8 installation on an HDD, using UEFI as boot. The HDD has the following GPT table: DISKPART> list partition Partizione ### Tipo Dim. Offset --------------- ---------------- ------- ------- Partizione 1 Ripristino 300 Mb 1024 Kb Partizione 2 Sistema 100 Mb 301 Mb Partizione 3 Riservato 128 Mb 401 Mb Partizione 4 Primario 390 Gb 529 Mb Partizione 5 Primario 540 Gb 390 Gb (I apologize it's in Italian, but the translation is quite straightforward). I recently bought an SSD drive, connected it and installed a fresh Windows 8. Now I have a working dual boot, but the UEFI partition is on the HDD instead of the SSD. Here's the SDD partition list: Partizione ### Tipo Dim. Offset --------------- ---------------- ------- ------- Partizione 1 Riservato 128 Mb 1024 Kb Partizione 2 Primario 221 Gb 129 Mb I think that the best solution would be to have it on the SSD for two reasons: the first is performance (I guess it would be a little be faster on the SSD due to the spin up time for an HDD, but I may be wrong about that) second reason is consistency. As I plan to use only the Windows 8 installation that is located on the SSD and I'm probably going to erase the system partition on the HDD to use it as a data storage device, I think that the boot partition should be on the same drive as the OS. So the question is how do I move the EFI System Partition to the SSD?

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• What can I do to determine the root cause of a Windows server hanging/freezing?

  - by Aaronaught

  We set up a new server here a few weeks ago that I am informally responsible for managing. Almost everything works perfectly except for one thing: Every so often it hangs without warning. To clarify: When I say hangs, I mean completely. None of the services respond and I'm unable to even get onto a local console - the display acts as though there's no VGA signal. One time, the server actually responded to pings, another time I got the "destination host unreachable" response, but most of the time the pings just time out, as one would expect for a hung server. Event logs don't show anything after a reboot. I don't mean that they don't show anything interesting, I mean that they don't show anything at all from before the failure occurs to after the reboot. And there are never any performance problems, strange errors, or other obvious signs of impending doom before it happens. I don't expect any easy answers here. What I'd like to know his I can methodically determine the root cause of this problem, be it a misbehaving service, defective hardware, or something else. Is there any kind of logging I can set up that will help me get to the bottom of this? Any hardware diagnostics or remote monitoring? Anything else I can do to help me discover what's actually happening, or at least be able to eliminate what isn't wrong? Just to reiterate, I really don't want to start speculating about possible causes and take a trial-and-error approach, because it's going to be at least several days at a time before I would have conclusive results. I'm looking for solutions to reliably trace the problem to its source.

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• Windows 7 Paging file apparently not being used

  - by Daniel F.

  I'm running Windows 7 Home Premium 32bit on a mobo with 24GB RAM. Of those 24GB, 20GB are assigned as a RAMDISK via ASRock XFastRAM. This RAMDISK has the drive letter X assigned to it. On X:\ I'm storing the temporary files folder, as well as pagefile.sys. Pagefile.sys has 6GB of size. The X:\ has usually around 14GB free space, so the temporary files are negligible, it's mostly the browsers which are storing their caches on there. Now my issue is that Firefox is crashing a lot on me, no error message pops up, but I know that this is because it's out of memory. I could kind of live with that, but now that I switched from using Eclipse to Android Studio, I know that I'm in trouble, because Java isn't capable of allocating, and Android Studio, together with the Java instances it launches, is quite a memory hog. So I tried to figure out what's wrong, and apparently Windows isn't swapping out memory onto the paging file. While my applications are crashing (firefox) / not starting (java vm's), the paging file is only using constantly around 15% of its size (checked with the performance monitor). 15% equals to 1GB aprox. I know that the correct solution would be to switch to 64 bit Windows, but I had to use the 32 bit version because of driver issues which I had about two years ago, and I guess that I'll have them again if I reformat and install the 64 bit version. Also, the machine is running quite stable, the only issue is the memory, so I'd like to use it as it is (as the apps are installed and configured) Is there a way to make Windows use the paging file more efficiently? None of my processes require more than 1GB, I'd just like it to swap out some seldomly used stuff, like GoogleCrashHandler.exe and stuff like that in order to have "more physical memory avaliable". Is that possible?

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• Flash Backed Write Cache (FBWC) without capacitor pack

  - by Martyn

  I brought a HP Smart Array P410 controller and it is installed and working fine in a HP Prolient Microserver with 4 drives in two RAID 1 arrays. I didn’t realise however that it came without any cache so would only work by directly writing straight to the disk, and the performance was horrible. So I then brought the 512MB Flash Backed Write Cache (FBWC) memory module as I was under the impression that with FBWC I would not need a battery. I got this idea from a forum post. "What do you guys think of the choice between 'BBWC' (battery backed write cache) and 'FBWC' (flash backed write cache)? The flashed based ones use non-volitile memory so need no battery." After installing the cache module however the server pretty much won’t boot. The P410 has a flashing amber light on it, and from the manual that doesn’t sound good. I’ve managed to get to the on board BIOS once and even managed to get to boot to the HP Array Configuration Utility (ACU) CD once, but every other time the Server continuingly reboots once it get to the POST screen and reads ARRAY INITILIZING %%%. The one time I reached the ACU, it reported a problem with the Cache Module. To me, it seems like the cache module is faulty, however the supplier tells me “Do you have an FBWC battery pack, p/n 587324-001, because that is required for the cache to work. If you have it, please complete an RMA form and we'll send a replacement / credit.” Does this sound right to you? I’ve been ordering the parts from the US and I don’t want to spend $77 + $40 p&p on a battery, wait a week for the shipping to find the card is faulty, and I don’t want to send back a working card?

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• Which CPU for XEN - LAMP testbed - Budget

  - by deploymonkey

  Dear serverfault knowledgeables, im in a decision dilemma right now, which I can't resolve due to lack of hands on experience. I need to build a testbed for basically virtualizing a LAMP application (os'ses not yet decided) including server side calculations. I'll opt for XEN since it seems better supported by cloud hosters at the moment. The hardware is for a proof of concept for a startup doing saas and might be used for closed live alpha/beta later on. After testing, the testbed might be a) deployed as a colocated white box server b) used as workstation Single socket is enough. We want to have ECC memory for reliability, this excludes most of the consumer line at intel. If intel CPU, then threaded cpu (HT) is preferred have at least 16 gig ram If justified by price and reliability is not too bad, a high quality desktop MB instead of a server MB would be worth a try It came down to the opteron 6128 vs. the xeon 5620 for me after a lot of research, but I don't necessarily have to be right. Which CPU is preferrable, concerning TCO (MB price, power requirements 24/7...) , Opteron 6128 or Xeon 5620? Which one offers better performance in real world applications? (Do You have any other suggestions I probably overlooked?) Thank You for Your consideration

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• Use external display from boot on Samsung laptop

  - by OhMrBigshot

  I have a Samsung RV511 laptop, and recently my screen broke. I connected an external screen and it works fine, but only after Windows starts. I want to be able to use the external screen right from boot, in order to set the BIOS to boot from DVD, and to then install a different OS and also format the hard drive. Right now I can only use the screen when Windows loads. What I've tried: I've tried opening up the laptop and disconnecting the display to make it only find the external and use the VGA as default -- didn't work. I've tried using the Fn+key combo in BIOS to connect external display - nothing I've been looking around for ways to change boot sequence without entering BIOS, but it doesn't look like it's possible. Possible solutions? A way to change boot sequence without entering BIOS? Someone with the same brand/similar model to help me blindly keystroke the correct arrows/F5/F6 buttons while in BIOS mode to change boot sequence? A way to force the external display to work from boot, through modifying the internal connections (I have no problem taking the laptop apart if needed, please no soldering though), through BIOS or program? Also, if I change boot sequence without accessing external screen, would the Ubuntu 12.1 installation sequence attempt to use the external screen or would I only be able to use it after Linux is installed and running? I'd really appreciate help, I can't afford to fix the screen for a few months from now, and I'd really like to make my computer come back to decent performance! Thanks in advance!

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• Wireless keeps shutting off in Windows 7

  - by Nathan Adams

  I have Windows 7 Ultimate 32bit installed on a Dell Latitude XT Tablet and for the life of me I can't figure out this really weird problem. The symptom is that the Wireless will disconnect from the AP and if I tell it to scan again, it says there are no APs in the area. I do have another wireless card in the laptop and if I disable the first one and enable the second, I am able to get onto the wireless however if I want to use the first card again I have to restart. I tried enabling/disabling the device, nothing will kick start the wireless again in the first card without a restart. I even tried different drivers. So, it seems it is random but it does occur more often when there is increased network activity (ie downloading a large file). The laptop doesn't seem to be overheating. I have tried the following: Under "Change Advanced Power Settings" for the current power profile, I set the "Wireless Adapter settings" to "Maximum Performance". Under device manger, I went to the card in question, and went to the advanced tab and set the "Power Saving mode" to "MAX_PSP" Both cards I have seem to exhibit the behavior after awhile. Both models of those cards are: Dell Wireless 1505 Draft 802.11n WLAN Mini-Card Gigabyte GN-WS30N 802.11n mini WLAN Card Has anyone have any ideas or ran into this before?

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• i7 Windows 7 laptop or Macbook Pro 15" (For making 3D model and Animation)

  - by sppdhs

  Hi everyone, I'm thinking of buying a new laptop as my current one will be 5 years old next year and it currently gives me a blue screen everytime I run a heavy software to make 3D models and animation. Question is: Should I buy Macbook Pro or a Windows 7 laptop? I tried to research and some say that Windows would be better, especially because you can buy a very high spec laptop with cheaper price. While some other say Macbook Pro is the better choice as it can run bootcamp with windows 7 100% performance on every software even though it's a mac. Is this true? Which one is actually better? Btw, the software that I usually use is 3Ds Max, Maya, and ZBrush. To note as well, I have never used a Mac before. I've checked around some stores and budget wise, I'll need around AU$3000+ to buy a Macbook pro, and AU$2000+ to buy a windows laptop. Quite a big difference in price range. Thanks in advance for your help.

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• MongoDB on 128mb 32-bit VPS (plus Tornado and Redis)

  - by apito

  i am curious about how mongodb will perform in a limited vps. specifically, i'll deploy this configuration on 32-bit ubuntu 9.04 server with 128Mb memory (UPDATE: now i'm considering 360mb too). nginx and redis three instances of tornado apps (one is for mobile site; limited app, not my primary audience); has around 8 Collections. social webapp for my community. mongodb all beside mongodb seems to have small footprint. memory-mapping-wise, i dont know how mongodb will behave. i know it's a little bit a stretch to use this kind of config on a tiny vps, but that's what i can afford for now. i expect to have.. hmm.. maybe ~50 15rps. i did my homework doing a lot of frontend optimizations and yslow says grade A 91 (ruleset V2) :-) anyone willing to share experiences? eg. how big the data set size when mongo hit the ceiling, performance when mongo do a lot of disk IO, etc. thanks. UPDATE: this is my pet project. i'll get back to you when i have next spare time to do same httperf in a vbox with exact spec. suggestion how to do stress testing welcomed. i'm new to this kind of stuff.

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• Windows/IIS Hosting :: How much is too much?

  - by bsisupport

  I have 4 Windows 2003 servers running IIS 6. These servers host a bunch of unique web sites (in that they are all different in build/architecture/etc). The code behind these sites range from straight HTML, classic ASP, and 1.1/2.0/3.x flavors of .NET. Some (most) of the sites use a SQL backend, which is hosted on one or two different servers – not the IIS servers themselves. No virtualization on these servers and no load balancing for these particular sites. The problem I’m running into is coming up with some baseline metrics to determine, or basically come up with a “baseline score” to know when a web server has reached its hosting limit. Today, some basic information about each server is used: how much bandwidth does the server pump out, hard drive space availability, and basic (very basic) RAM & CPU utilization (what it looks like at peak traffic times.) I would be grateful if those of you that are 1000x smarter than I am could indulge me with your methods of managing IIS environments. Whether performance monitoring specifics, “score” determination as I’m trying to determine, or the obvious combination of both. Thanks in advance.

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• Upgrading memory in a laptop

  - by ulidtko

  I'm a bit confused about all the memory types and various bus frequencies of modern consumer PCs. Requesting expert help on the subject. So far I'm confident that: I have an Asus X51L laptop with an unknown set of configuration options. The CPU in there supports PAE, so I still have a chance to extend the memory beyond 3GiB; and the upper limit of the system is 8GiB. (?) The laptop has two SODIMM slots, one of which is occupied by a 2GiB bank, and the other one is empty. dmidecode and lshw tools consistently state 533 Mhz frequency of the bank. The last one confuses me the most. I failed to find out characteristics of the northbridge in this laptop, and still can't figure out what DDR2 to seek for. Is it DDR2-1066? Or, rather, PC2-8500/PC2-8600? Wouldn't a DDR2-800 bank harm the system's performance? Which kind of modules should I look up in stores? Update: I have bought a 2 GiB DDR2-800 SODIMM, and it seams that the system can't handle 4 GiB of memory. When installed by itself in either slot, both new and old bank (which btw happens to be marked GDDR2-677) work just perfectly; i.e. any configuration resulting in 2 GiB works. When both banks are installed though (totalling in 4 GiB), the memcheck86 tool produces horrible artifacts and crashes, and system reboots; an Ubuntu system can be started and even logged into a Unity session, but the system reboots too in this case from even a minor RAM load. So it's pretty obvious to me now that this laptop doesn't support 4 GiB of RAM or more.

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• How to speed up request/response to django using apache or another solution?

  - by jbcurtin

  Hey all, I'm mainly a developer, but every now and again I jump into the sys-admin position. For the most part I've gotten away with deploying php and python apps using apache. I write today because I'm starting to research faster alternatives to apache, yet still have some of the core features I require like put and delete methods and the ability to connect to a socket via apache. ( This I have not tried, but might be a nice whistle if I ever employ comet on my apps. ) As you've probably guessed, I use javascript exclusively for all my websites utilizing deep linking for SEO support. The main areas that I'm looking to increase performance is the connection between the django apps and the web server to the client response. Every day I work my best to keep the smallest memory foot print as possible, however I am getting to the end of my rope when it comes to working with apache. In general, keep in mind that I'm just starting this research so I'm looking more for material to read then solutions at this moment. My main questions: Am I missing something about apache that makes it faster then everything else? What would be a good server environment to deploy just static files one? What are some of the leading open-source and paid alternatives?

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• Looking for some IIS redirect help/ideas

  - by CoreyT

  Right now we have a site with a LOT of static asp pages such as, www.site.com/123.asp. This is due to how our current site's CMS builds it's pages by default. I don't have an exact count but we have roughly 6000 asp files in the site right now. We are in the middle of a redesign and restructuring of the site, and are looking to migrate to SEO friendly URLs. The problem we're having right now is what do we do to redirect the old pages to the new friendly URLs? I know how to do redirects that is not the issue here. The problems I am coming up with right now are listed below. 1 - Is there a limit to the number of redirects in IIS? 2 - Would having even a few thousand redirects affect IIS performance? 3 - My understanding is that we would not be passing along page rank to the new URLs, is that true? (not a major question I can ask on more SEO forums if nobody here is sure) 4 - Would using something like the IIS URL Rewrite 2 module for IIS 7 help us out? Or would I still need to define several thousand unique redirects in it? Our server right now is running Server 2003, however in the redesign I would be open to migrating to Server 2008 R2 if there is a good case for it (i.e. the URL Rewrite module). Thanks for any guidance or help. I have been looking for a good way to do this for a while now and keep coming up with things that sound problematic and bad (such as having 6000 redirects).

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• Is 2 GB of RAM better than 2.5 GB?

  - by pibboater

  My laptop has two slots for RAM, and currently has two 512 MB chips, for 1 GB. Windows XP is running terribly slow on it, so I want to upgrade the RAM. I could buy two 1 GB chips to replace both of the current 512 MB chips, to give me 2 GB of RAM. Or, the price is the same to buy one 2 GB chip, to replace just one of the 512 MB chips, and give me 2.5 GB total. The RAM it takes is PC2-4200 533MHz DDR2. What do you think would be better: buying two 1 GB chips so it can take advantage of dual-channel operation, or buying one 2 GB chip to end up with more total RAM but not dual-channel operation? Like I said, price is the same, so performance is the only consideration. I'm not doing anything especially intensive like video or photo editing -- just having multiple Office programs open, playing music, browsers, etc., but currently even opening the first application takes forever. If it matters, the laptop is a Toshiba Qosmio G25-AV513 running Windows XP Media Center SP3. Thanks! Kevin

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• using i7 "gamer" cpu in a HPC cluster

  - by user1219721

  I'm running WRF weather model. That's a ram intensive, highly parallel application. I need to build a HPC cluster for that. I use 10GB infiniband interconnect. WRF doesn't depends of core count, but on memory bandwidth. That's why a core i7 3820 or 3930K performs better than high-grade xeons E5-2600 or E7 Seems like universities uses xeon E5-2670 for WRF. It costs about $1500. Spec2006 fp_rates WRF bench shows $580 i7 3930K performs the same with 1600MHz RAM. What's interesting is that i7 can handle up to 2400MHz ram, doing a great performance increase for WRF. Then it really outperforms the xeon. Power comsumption is a bit higher, but still less than 20€ a year. Even including additional part I'll need (PSU, infiniband, case), the i7 way is still 700 €/cpu cheaper than Xeon. So, is it ok to use "gamer" hardware in a HPC cluster ? or should I do it pro with xeon ? (This is not a critical application. I can handle downtime. I think I don't need ECC?)

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• How do I repartition an SDHC card in Windows?

  - by Peter Mortensen

  How do I repartition an SDHC card (4 GB or more)? Do I need third-part tools or Linux (a live CD solution would be OK)? In Windows' Disk Management the option Delete Partition is dimmed out: I can reformat the card as FAT32, copy files to and from the card and even change the file system to NTFS using the command line command CONVERT, but not repartition it. The article How to Partition an SD Card in Windows XP talks about using "a Windows enabler program" which sound rather dubious to me. I have tried to change from “Optimize for quick removal” to “Optimize for performance”. The option to format as NTFS appeared, but the Delete Partition option is still dimmed out. Platform: Windows XP 64-bit SD card reader: USB 2.0 device, LogiLink® CR0005C Cardreader 3,5' USB 2.0 intern 54-in-1 mit USB Front Kingston 16 GB SDHC card, speed class 4. (It could be formatted as FAT32 and successfully used in a 4 GB ReadyBoost setup (Windows 7).) I have also tried on different versions of Windows and with different cards with the same result: Kingston 4 GB SDHC card, speed class 4 (the one shown in the screenshot) Transcend 2 GB (not marked as SDHC, but SD) Windows 7 32-bit (albeit with a somewhat an older card reader) and Windows XP 32-bit on an EliteBook 8730w

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• SSD as primary or secondary drive on a small Linux server?

  - by Alex Martelli

  I'm pensioning off my 10-years-old home server and replacing it with an Ubuntu 10.04 box. The two storage devices are a Western Digital Caviar Green 2.0TB HD and an Intel X25-M 34nm Gen 2 80GB SATA II 2.5inch SSD (the box has 8GB RAM and an i5 750, if it matters). I don't care much about boot times (since I don't plan to reboot all that often;-); the main frequent, performance-demanding task will be (re)building large open source C or C++ software packages from sources (as an open source contributor, I do that often). So, I thought I'd keep the SSD as the secondary drive and the HD as the primary one, using the SSD mostly for the files that can otherwise demand a lot of seeking (esp. in a parallel make). However, the friendly vendor (perhaps more experienced in Windows systems than in Linux ones) thinks the "normal" way to configure the machine would be with the SSD as the primary drive. I'm pretty rusty on configuring and tuning systems, so, I thought I'd better double check on SuperUser... thanks in advance for advice about this choice!

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• Setting up a global MySQL Cluster in the cloud

  - by GregB

  I'm giving the question an overhaul to more specifically identify where I need help. I use two tools to manage a bunch of cloud server: Puppet and Rundeck. Both of these can be configured to use a mysql backend. I'd like to setup an instance of each application in both the U.S., and the U.K., treating the U.K. servers as hot stand-bys in case of failure in the U.S. I want to use a MySql cluster so that the data is automatically replicated from the U.S. to the U.K. Because these are hot standbys, high performance is not a goal. Redundancy and data integrity are most important. My question revolves around the setup of the mysql cluster. I want to run three servers, each one running a data node, a sql node, and a management node. Is this a valid configuration for mysql server? If so, could someone point me in the right direction for creating such a setup? I've downloaded the offical tarball, and the official debian, and the documentation for them contradicts many of the online tutorials. I'm installing on Ubuntu 10.04.

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• one 16K random read I/O issues 2 scsi I/O (16K and 4K) requests in linux

  - by hiroyuki

  I noticed weird issue when benchmarking random read I/O for files in linux (2.6.18). The Benchmarking program is my own program and it simply keeps reading 16KB of a file from a random offset. I traced I/O behavior at system call level and scsi level by systemtap and I noticed that one 16KB sysread issues 2 scsi I/Os as following. SYSPREAD random(8472) 3, 0x16fc5200, 16384, 128137183232 SCSI random(8472) 0 1 0 0 start-sector: 226321183 size: 4096 bufflen 4096 FROM_DEVICE 1354354008068009 SCSI random(8472) 0 1 0 0 start-sector: 226323431 size: 16384 bufflen 16384 FROM_DEVICE 1354354008075927 SYSPREAD random(8472) 3, 0x16fc5200, 16384, 21807710208 SCSI random(8472) 0 1 0 0 start-sector: 1889888935 size: 4096 bufflen 4096 FROM_DEVICE 1354354008085128 SCSI random(8472) 0 1 0 0 start-sector: 1889891823 size: 16384 bufflen 16384 FROM_DEVICE 1354354008097161 SYSPREAD random(8472) 3, 0x16fc5200, 16384, 139365318656 SCSI random(8472) 0 1 0 0 start-sector: 254092663 size: 4096 bufflen 4096 FROM_DEVICE 1354354008100633 SCSI random(8472) 0 1 0 0 start-sector: 254094879 size: 16384 bufflen 16384 FROM_DEVICE 1354354008111723 SYSPREAD random(8472) 3, 0x16fc5200, 16384, 60304424960 SCSI random(8472) 0 1 0 0 start-sector: 58119807 size: 4096 bufflen 4096 FROM_DEVICE 1354354008120469 SCSI random(8472) 0 1 0 0 start-sector: 58125415 size: 16384 bufflen 16384 FROM_DEVICE 1354354008126343 As shown above, one 16KB pread issues 2 scsi I/Os. (I traced scsi io dispatching with probe scsi.iodispatching. Please ignore values except for start-sector and size.) One scsi I/O is 16KB I/O as requested from the application and it's OK. The thing is the other 4KB I/O which I don't know why linux issues that I/O. of course, I/O performance is degraded by the weired 4KB I/O and I am having trouble. I also use fio (famous I/O benchmark tool) and noticed the same issue, so it's not from the application. Does anybody know what is going on ? Any comments or advices are appreciated. Thanks

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• Disk Activity Alert Windows SBS 2003 on Dell PowerEdge 830 with Raid

  - by Ron Whites

  Background: I have a Dell PowerEdge 830 Server running Windows SB Server 2003. It has 4gbs of RAM and a ATA CERC SATA 6CH controller with 3 160gb drives in a Raid 5 configuration. The Problem I am seeing Admin ---"Disk Activity Alert on Server" emails These often occur when disk backups, de-frag or high disk usage is going on. Generally the server isn't over stressed. The Disk Alert emails say in part ... The following disk has low idle time, which may cause slow response time when reading or writing files to the disk. Disk: 0 C: F: D: Review the Disk Transfers/sec and % Idle Time counters for the PhysicalDisk performance object. If the Disk Transfers/sec counter is consistently below 150 while the % Idle Time counter remains very low (close to 0), there may be a problem with the disk driver or hardware. The Questions I have: With what utility can I review the Disk Transfers/sec and Idle Time? It appears there is no utility for that on the server! I think I may need to download a very large (two DVD) Dell "OpenManage" utility to be able to monitor the raid system and see what is a problem is that true?

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• Master File Table Corrupt, any way to save data?

  - by domen

  hi. I've used search, but none of the results match my problem so I didn't have to ask separate question. I've Installed Windows 7 RTM recently and since then partitions located on one of my HDDs have gone "crazy". They used to "freeze" and didn't open in explorer for some time (minute or two, usually), sometimes all partitions of the drive wouldn't show until reboot and finally, one of those partitions started showing "disk structure is corrupted and unreadable" warning, it appeared in Disk Management window as RAW and chkdsk showed "mft corrupt". There were no important data on the partition and I didn't have enough time to analyze the problem at the moment, so I just reformatted it and ran antivirus scan on system. After that problem settled for some time, but yesterday the problematic HDD vanished again from the system. After reboot chkdsk identified mft of four partitions corrupt and now they are all in same conditions as the above mentioned one. But the difference is that the files stored in them are extremely important. and just for info: I upgraded from Win7 build 7077, but had some performance issues, so I reformatted system drive and installed fresh Win7 RTM on it. I've downloaded TestDisk and it shows all the partitions marked as NTFS (not RAW) and my knowledge of the program wasn't sufficient to obtain any other info from it :-) and the images that could help describe the problem (sorry, I'm not allowed to post images and more than one hyperlink): http:// img22.imageshack.us/img22/5909/chkdskz.jpg http:// img198.imageshack.us/img198/5576/computeray.jpg I'm interested, is there a way to let me restore the MFT or just access files so I can backup them before reformatting the drive. Thanks for your time. :) P.S. my reformatted drive is showing no problems, could there be a problem with windows 7 itself? I googled, but with no results.

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• Server 2003 and SSL Certificates

  - by Keith Stokes

  I have a Windows 2000 domain with dozens of Windows 2000 servers and a few 2003 servers. Each server runs a custom app talking to a 3rd party utilizing self-signed certificates. To help troubleshooting we've created a custom test app. The 2000 servers are able to talk within seconds. The 2003 servers take anywhere from 10-30 seconds using a domain account and much less, usually under 5 seconds using a local account. The only exception to the local account performance is a new account, which is slow initially then faster. If you leave the test app open and reconnect repeatedly it talks in seconds. If you leave it open for sometime between 1 and 2 hours, it reverts back to the previous 10 seconds, so obviously something is caching. Installing the destination certificates in the local 2003 server store makes no difference. I've installed the certificates in AD and that apparently makes domain accounts work in 9-12 seconds, vs 30 seconds that was regular before. Manually clearing the certificate store on the 2003 server makes no difference. I'm at a loss as to where the certs might be cached and if I'm using some sort of domain certificate store that's hiding from me.

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