Stripe and cluster size

scottscott Medina, Ohio Icrontian
edited October 2003 in Hardware
I did a wipe and reformat this weekend and changed my stripe size to 16K it seemed it would be a major pain to change cluster size on the OS partition so I left it at the default 4kb. I formated the other two partitions at a cluster size of 8 and 16. I then ran atto and sandra on all three partitions a couple of times. Atto did not show any appreciable difference. But Sandra gave much better results to the 16/16 setup.
Question....Can I have two partitions configured one way and the OS partition configured another ? Or will this cause problems.
As it stands now
Partition C 4/16
D 16/16
E 16/16

Intel onboard Raid 0
2x wd 120's
OS xp pro sp1

Scott
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Comments

  • primesuspectprimesuspect Beepin n' Boopin Detroit, MI Icrontian
    edited October 2003
    That is not a problem. Each partition can have whatever stripe/cluster size you want.
  • TexTex Dallas/Ft. Worth
    edited October 2003
    And actually you can easily change the cluster size even with data on it with PM8 now.

    Tex
  • Mt_GoatMt_Goat Head Cheezy Knob Pflugerville (north of Austin) Icrontian
    edited October 2003
    There are many things that affect performance, including size of a partition, how far in on the disc it is, what percentage is freespace and in the case of ATTO what else is going on at the very instant. For ATTO I always run it at least 5 times and average the scores to determine how a particular partition or drive is performing. Sandra is less affected by environmental variables but is still not a defacto test. One thing to make certain of with any storage system test is fully defrag what you are testing first. Even if it is an empty drive and you have run several tests on that partition the test itself will leave behind little bits and pieces that can change your scores.


    You can easily redo your C drive if you have Ghost and a spare drive by Ghosting to the other drive, change your boot order in the bios to boot from the other drive and change the stripe and cluster then Ghost back to C again. It will never know the difference except by running better. :)
  • scottscott Medina, Ohio Icrontian
    edited October 2003
    Here are some atto's of C & D

    Would you change the the cluster size on C ?

    Scott
  • scottscott Medina, Ohio Icrontian
    edited October 2003
    Here are the Sandra results
    The first line is Drive E
    The second is D
    The third is C

    This is a SATA 150 raid 0 setup so I used the sandra referance for such. Both the ATTO's and the sandra results were done after a fresh defrag with nothing running except the normal XP services.
    Is it worth messing with or should I just leave it. The OS is on C and everything else is on the partitions.

    Scott
  • Mt_GoatMt_Goat Head Cheezy Knob Pflugerville (north of Austin) Icrontian
    edited October 2003
    That looks pretty good so far. :thumbup

    If you change C to 16/16 it will reduce the CPU overhead since it won't need to switch from one drive to the other as often. Then your C score will be better than your D score due to being closer to the rim of the disc. You will thus see an improvement in your RAID-0 scores/performance and CPU utilization. Have you messed with the PCI latency yet with something like "Powerestrip"? If you are not familiar with it then check it out here.

    step2.jpg
  • scottscott Medina, Ohio Icrontian
    edited October 2003
    I do not have a ghost program. But I do have PM7 but have never used it. Tex do you know if I can change cluster size with data on the partition with PM7?

    Mt I can not change latency with powerstrip. We discussed this in another thread. HERE ( Intel has locked it out ) I do have the ability to change latency in Bios. I had it at 192 and bumped it up to 224 It seemed to help on C but not on D or E
    So How about PM7?
  • scottscott Medina, Ohio Icrontian
    edited October 2003
    We'll I loaded PM 7 and apperently the resize cluster option is only available for FAT file systems. I guess I will look into a drive image tool. Any thoughts on a good one ?
  • Mt_GoatMt_Goat Head Cheezy Knob Pflugerville (north of Austin) Icrontian
    edited October 2003
    Sorry about that Scott as I just lost track. It looks like you made real good progress since out last encounter! :)

    PM8 allows it but I never tried it with data on a disc.
  • SpinnerSpinner Birmingham, UK
    edited October 2003
    Paragon Disk Manager, and Partition Magic 8 can resize the cluster size (NTFS), and I've used both applications many times with data and OS on the partitions in question, with no trouble what so ever.
  • PreacherPreacher Potomac, MD Icrontian
    edited October 2003
    Spinner had this to say
    Paragon Disk Manager, and Partition Magic 8 can resize the cluster size (NTFS), and I've used both applications many times with data and OS on the partitions in question, with no trouble what so ever.

    I second Spinner's comment. I've used both and have had great success every time.
  • SimGuySimGuy Ottawa, Canada
    edited October 2003
    I'm a complete n00b when it comes to cluster sizes on RAID arrays. Calling all RAID guru's!

    What is the most "optimal" setting for cluster sizes when it comes to a RAID-0 array that you want the best read/write performance out of?

    As well, what is each of the X/X cluster size mean? For example, with a size of 4/16, what does the "4" represent and what does the "16" represent?

    I'm trying to get the best performance out of a RAID-0 array of dual 36.7 GB WD Raptors. First cluster size I used was the default "64" on a Promise SATA controller. ATTO's were pretty abysmal. Writes hit 95 Mb/sec and reads were 66 Mb/sec.

    Switched to Intel ICH5R RAID-0 with a cluster size of "128" and got ATTO write scores through the roof, but the reads only increased ever so slightly.
  • MediaManMediaMan Powered by loose parts.
    edited October 2003
    wheeee!

    Course those scores suck for my setup. 4 x scsi raid 0. Couldn't decide whether to go 16k or 128k. So I played safe in the middle as the AMI Elite 1600 apparently is optimized for 64k stripes.
  • Mt_GoatMt_Goat Head Cheezy Knob Pflugerville (north of Austin) Icrontian
    edited October 2003
    SimGuy,

    First you need to change the "Total Length" setting in ATTO to 32mb and re-test before going any farther. I have doctored your attachment and circled what you need to change before running a test. You will need to do this all the time so that it runs correctly.
  • scottscott Medina, Ohio Icrontian
    edited October 2003
    I downloaded paragon 5.5 Trial version
    You guessed it ....The resize feature is "Not available " in the trial download. The program is a bit pricey for a one time deal. I really do not know how often I would use it. I do not think I can justify buying it.
    Like I said 'oh well ' :banghead:

    Scott

    Could I rent it from somebody?
  • MediaManMediaMan Powered by loose parts.
    edited October 2003
    Odd how your graph is somewhat opposite mine. Wonder why? And how you go those nice scores. I loaded powerstrip but all it would detect was the video card and not the 64bit AMI Elite 1600.
  • Mt_GoatMt_Goat Head Cheezy Knob Pflugerville (north of Austin) Icrontian
    edited October 2003
    MediaMan had this to say
    Odd how your graph is somewhat opposite mine. Wonder why? And how you go those nice scores. I loaded powerstrip but all it would detect was the video card and not the 64bit AMI Elite 1600.
    Sometimes a device in Powerstrip is listed by it's internal hardware rather than by what we know it as so what I do is go to: msinfo32.exe to find the device and look to see what IRQ it is on and see if it has a name extension. Then I go back to Powerstrip and find the IRQ (next to latency setting) and find a device with the same IRQ (works better if a controller is the only thing on an IRQ) and use that device.

    That was SimGuy's graph that I doctored to show him where to adjust "Total Length" prior to running the test.

    Here is one of mine, 2 WD1000JB's on my HPT 1520:
  • SimGuySimGuy Ottawa, Canada
    edited October 2003
    mtgoat had this to say
    SimGuy,

    First you need to change the "Total Length" setting in ATTO to 32mb and re-test before going any farther. I have doctored your attachment and circled what you need to change before running a test. You will need to do this all the time so that it runs correctly.

    Done! :)

    Is this considered good disk performance? I'm pretty new to RAID and I have no idea what to expect. All I want is the best read & write performance available on 2 SATA-150 10K RPM drives in RAID-0.
  • Mt_GoatMt_Goat Head Cheezy Knob Pflugerville (north of Austin) Icrontian
    edited October 2003
    Looks like an improvement to me. :thumbsup:

    Couple of things.
    * Since I see it is on the Intel controller I do beleive you are in the same boat as Scott and will not be able to adjust your latency to fine tune it.

    * What do you plan on using the array for? System, edit video or something else?

    * Generally 16 or 32 for a stripe size with 16 cluster size is optimal for most use while 128 stripe/ 32 cluster or 128/ 64 is better for video editing or other uses where you deal with nothing but very large files on the drive. The later is also not as efficient on drive space if used for anything but very large files and transfers.
  • MediaManMediaMan Powered by loose parts.
    edited October 2003
    arrrrrgh.

    Just...o so close...swing and a miss.
  • ShortyShorty Manchester, UK Icrontian
    edited October 2003
    Now that is more the kind of performance I would have expected :eek:

    Yowsahs :bawling: so sweet!
  • SimGuySimGuy Ottawa, Canada
    edited October 2003
    Just out of curiosity, what is your SCSI setup MM?
  • SimGuySimGuy Ottawa, Canada
    edited October 2003
    mtgoat had this to say
    Looks like an improvement to me. :thumbsup:

    Couple of things.
    * Since I see it is on the Intel controller I do beleive you are in the same boat as Scott and will not be able to adjust your latency to fine tune it.

    * What do you plan on using the array for? System, edit video or something else?

    * Generally 16 or 32 for a stripe size with 16 cluster size is optimal for most use while 128 stripe/ 32 cluster or 128/ 64 is better for video editing or other uses where you deal with nothing but very large files on the drive. The later is also not as efficient on drive space if used for anything but very large files and transfers.

    Yep, it's on the ICH5R I/O Controller Hub of the i875 chipset, so you can't adjust the latency timings.

    The array is my System drive, storing a dual-boot between Windows XP and Windows LongHorn 4051, along with storing all my documents. Applications are stored on another 250 GB RAID-0 array. It won't be used for the storage of massive media files for editing.

    Forgive my n00bness, but what is stripe size? I know cluster size, but what exactly is stripe size?
  • ShortyShorty Manchester, UK Icrontian
    edited October 2003
    SimGuy had this to say
    Forgive my n00bness, but what is stripe size? I know cluster size, but what exactly is stripe size?

    :eek::eek::eek: The mighty SimGuy is really a n00b :eek::eek::eek::D

    Ok.. stripe size is the bit size set in the controllers BIOS. It determines the size of the chunks of data that it's striping. That's why cluster size generally should match :)

    Eg.. a 128kb file is written to 2 drives (in a 2 drive RAID-0) with a 64kb stripe...

    Drive 1 - 64kb
    Drive 2 - 64kb

    If the file was written with 32kb stripe.. the controller would do this..

    Drive 1 - 32kb
    Drive 2 - 32kb
    Drive 1 - 32kb
    Drive 2 - 32kb

    That's why when deciding the use for your array, you analyse what size files you are going to put on there. If you had lots of tiny files, a small stripe size works well. Big ass encoding would hammer a small stripe size, so in that instance a big stripe size like 64kb or 128kb would be more efficent :)
  • SimGuySimGuy Ottawa, Canada
    edited October 2003
    LOL, Yes I'm a complete RAID-n00b. I was happy with U/100 IDE drives until I noticed that RAID increases performance substantially. :D

    So with my 128 KB size (I think it's stripe size) on both Raptor drive, each HDD is getting 64 KB's written to it each and every pass with a 128 KB file?

    So, if the majority of my files are driver files and application files which are less than... lets say 64-256 KB a piece, what's the best way to tune the RAID array's Stripe Size for optimal read/write performance. AFAIK, Cluster Size = 4 KB for NTFS on these drives, but I could be wrong :D

    //Edit: Yep, it's 4 KB. :D
  • TexTex Dallas/Ft. Worth
    edited October 2003
    I see MediaDude got my scsi raid tweaking tips and has been playing. Way to go ace!

    Glad you are really liking the drives and controller ! They are sweet.

    I am scarfing for more drives big time as we speak. I feel almost naked with so few drives myself.

    I hit 300,000 with mine when I had the damn write cache on the drives disabled in the firmware still. Pain in the butt enableing them in the scsi mode pages one at a time and saving it off but worth it. Good grief.

    I need to take a break today and take another shot now that they all seem to be running right for once and see how much the write scores pick up. 3 of the u320 drives I have now hit 65,000 on atto and the other 5 hit over 72,000 a piece so I am hoping for some better scores.

    Tex
  • Mt_GoatMt_Goat Head Cheezy Knob Pflugerville (north of Austin) Icrontian
    edited October 2003
    SimGuy,

    Yes, you pretty well got the idea. I would set it at 16/16 then you will have the best all around performance for your intended useage. Also, If you put the apps on the raided drive they will load much faster. Then put all your mass storage and back-up (got to have back-up w/ RAID-0) on the large disc. An Idea of how I like to do it.

    Raid drives
    partition 1 = 8-10GB, Windows and all associated
    partition 2 = 5- 8GB, temp, temp internet, my documents,etc
    partition 3 = All non Windows apps

    Large Drive
    partition 1 = ???, Back-up files
    partition 2 = ???, Storage

    If you need 2 partitions on the raided drive for other things you could put the temp, temp internet, my documents,etc in a folder on the apps partition. By putting the temp, temp internet, my documents,etc off your OS partition it will not become fragmented as fast. For RAID-0 to work well it needs to be as unfragmented as possible. Using this system I almost never need to defrag my OS partition as it never goes to less than 98% unfragmented. Some people like to make their partitions just barely large enough to hold the OS but I like to make it bigger so that there is room for those things that just end up going there to have room along with leaving room to defrag. I also know that drives work best when less than full. For this reason I have filled partitions to various %'s of capacity and found that 75% used is the limit for efficiency with 66% being much better.
  • MediaManMediaMan Powered by loose parts.
    edited October 2003
    SimGuy had this to say
    Just out of curiosity, what is your SCSI setup MM?

    AMI 1600 Elite controller with 128 MB ram.
    4 x 18GB Atlas 10k III drives RAID 0 64kb Stripe. Drives are striped Drive 0 channel 1, Drive 0 Channel 2, Drive 1 Channel 1, Drive 1 Channel 2. (Stripe is across the channels not down)

    All partitions are 64kb clusters but I could only get C drive to 32kb even with PM8. My C drive is only 5 GB partition and a 7 or 8 GB partition would probably have allowed 64kb clusters but I didn't want a C drive with a lot of wasted space.

    On Channel 2 drive 3 sits a 9 GB SCSI drive that has the page file and temporary system files. I would have gone RAID 0 as I have another 9gb drive but....didn't have the extra power adapter for that drive.

    SCSI controller is set to DIRECT I/0 Write thru.

    Everything was set up via the CTL-M route with the AMI setup utility. CTL-H would be used for recovery.

    All drives, controllers and tweaking guidance are courtesy of my good friend TEX who turned me over to the SCSI side. I could not have done it without him.

    :)


    I could probably get to 240,000 or 260,000 but that would involve another day or two of tweaking and I've got to get busy on other things. Getting to that level would be a matter of just pegging the scores but the desktop feel wouldn't be that much different. Right now...nice and smooth.

    Bought a DVD recorder yesterday and that is so sweet for backing up my ghosted partitions. REALLY saves my bacon in the future for putting things back the way they were if ever a crash should happen.
  • TexTex Dallas/Ft. Worth
    edited October 2003
    MediaMan had this to say
    SimGuy had this to say
    Just out of curiosity, what is your SCSI setup MM?
    All partitions are 64kb clusters but I could only get C drive to 32kb even with PM8. My C drive is only 5 GB partition and a 7 or 8 GB partition would probably have allowed 64kb clusters but I didn't want a C drive with a lot of wasted space.

    That would only happen if you were using that yucky old fat32 and not ntfs as it has no such limitations. (grin)

    I make 1gb partitons and can format them with 64k with ntfs.

    Cheers

    tex
  • SimGuySimGuy Ottawa, Canada
    edited October 2003
    Okay... so after reading this thread, it looks like it is possible to change the NTFS cluster size of disks with PM8 without having to re-format them (which is a bonus).

    However, can you change your RAID stripe size without destroying the array? If so, how exactly would I do that?
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