Results 1 to 16 of 16
  1. #1

    How much difference between SCSI and SATA ?

    Dear friends:

    can you tell me how much difference between SCSI and SATA ?
    thx

  2. #2
    Difference in what?

    Speed, quality, performance, price, etc?
    SuperWebHost.com, a Digitally Justified Company
    Celebrating our 9th year in Business

    Proudly Hosting with CANADIAN bandwidth
    Managed Hosting, Multi-Domain Hosting, Colocation, Merchant Accounts

  3. #3
    Join Date
    May 2003
    Posts
    1,664
    Lot of difference in price and disk space. Speed wise the SCSI will be a little faster. The quality of the drives will be quite similar these days also.

  4. #4
    Originally posted by VanHost
    Difference in what?

    Speed, quality, performance, price, etc?
    thx for your response
    i want to konw the difference of Speed, quality, performance

    thx

  5. #5
    Join Date
    Jul 2004
    Location
    Reporting Live from Marrz
    Posts
    254
    Originally posted by kris1351
    Lot of difference in price and disk space. Speed wise the SCSI will be a little faster. The quality of the drives will be quite similar these days also.
    I wouldn't agree. SCSI drives even SCSI-160 ones are much faster than SATA drives, and SCSI-320... not even to mention.

  6. #6
    Speed and quality is a noticiable difference. Depending on what it is you are using the drives for, my recommendation could be for either.
    SuperWebHost.com, a Digitally Justified Company
    Celebrating our 9th year in Business

    Proudly Hosting with CANADIAN bandwidth
    Managed Hosting, Multi-Domain Hosting, Colocation, Merchant Accounts

  7. #7
    Join Date
    Jun 2003
    Location
    Myrtle Beach, SC
    Posts
    75

    HD Performance Summary

    There are a few Tiers of features to look for in disk drives -- and I'll outline them here:

    Rotation Speed (RPM)

    Common Rotational Speeds:
    5400RPM - desktop
    7200RPM - high performance IDE, standard SATA
    10,000RPM - high performance SATA, SCSI
    15,000RPM - High performance SCSI

    SCSI takes the cake here -- offering the highest possible speeds at 15,000RPM -- however the WD Rapter SATA Drives also offer 10,000RPM rotational speeds, which is what you'll find for most SCSI drives.

    Rotation speed comes in involving how fast it can transfer data off the drive -- along with seek times (how fast it can get to and retrieve a specific piece of data)

    Typically the RPM speed is in no way restrained by the interface, (see Other Considerations below) -- so the faster your RPM, the faster your drive performance.


    TCQ - Tagged Command Queuing

    This is a little talked about feature, which has been with SCSI for years, giving it the advantage over other drives.

    Essentially, as drive commands queue up in the drive cache, the on-drive controller reorders the operations to access them most efficiently, so as the drive head moves across the platter it doesn't waste time re-seeking to a new location if the next operation was 'on the way' -- it'll perform them with minimal seek.

    Although this was predominately a SCSI feature -- it can now be found on the WD Raptor 73GB Model, and some high end 7200RPM IDE Seagate (or was it IBM) models --


    Interface

    Speed: SCSI currently leads the pact in regards to Interface speed with 320Mb/sec SCSI 3
    However, this is a moot point if you're limited by a slow drive, or you only have one drive. Interfaces in general matter when dealing with multiple drives on an interface -- for example having multiple drives connected to the same SCSI Channel could really max out that 320MB/sec --
    however SATA uses single-channel 150MB/sec Interfaces, which is more than sufficient for a single drive --

    IDE Now has ATA-100 or ATA133 (Maxtor)
    Which as far as an interface is concerned is more than efficient for a SINGLE drive connected to the channel (see Other Considerations below)

    Size

    - Drive size could both hurt or help you -- The thing to keep in mind is the number of platters the drive has, and how many heads it has -- This could affect seek times.

    Other Considerations

    Chaining IDE Drives:
    The IDE Interface is designed to perform ONE operation per cycle on a Channel. This means if you have TWO drives on the same IDE Channel it will only be able to read/write to one of them at a time.

    This is a HUGE performance consideration when you take into account copying between drives, or trying to read/write across two drives that are configured to the same Channel.

    Ask your host to put the drives on their own IDE Channels if Possible, and your performance will be greatly increased.


    Summary

    If your host isn't going to tell you specifically which model of IDE/SATA drive you're going to get -- then don't expect much -- you WON'T receive the much more expensive WD Rapter, OR the IDE Drives with TCQ -- in this case, go for SCSI to get those speed advantages.

    If you're building your own server -- then you can likely get close to SCSI speed, at less cost by going with WD Raptor 73GB Drives.

    If you're stuck with IDE -- at least make sure you're getting 7200RPM Drives, and demand they each be put on their own IDE Channel.
    Last edited by LogicX; 04-19-2005 at 02:19 PM.
    ---
    May this post be indexed by spiders, and archived for all to see as my internet epitaph.
    MikeSchroll.com

  8. #8
    Very nice post LogicX.....explains it quite well (and I even learned something there )
    SuperWebHost.com, a Digitally Justified Company
    Celebrating our 9th year in Business

    Proudly Hosting with CANADIAN bandwidth
    Managed Hosting, Multi-Domain Hosting, Colocation, Merchant Accounts

  9. #9
    very good


    thx very much

  10. #10
    Join Date
    Jan 2005
    Location
    San Francisco/Hot Springs
    Posts
    988

    Re: How much difference between SCSI and SATA ?

    Originally posted by yesgo
    can you tell me how much difference between SCSI and SATA ?
    There's quite a bit of difference, but both are quite handy.
    SATA is a lot better than IDE IMHO, but SCSI/FCAL are always what I'll use on a serious high end server.
    AppliedOperations - Premium Service
    Bandwidth | Colocation | Hosting | Managed Services | Consulting
    www.appliedops.net

  11. #11
    Night and day!

    SATA has it's place, it's in the desktop. We run SCSI drives in all our equipment, even our desktops!

    The problem with SATA isn't so much the drives, per se, it's more of a controller issue. Most of these no-name server manufacturers that end up in the 79/month plans use Highpoint, Via, Sis, Sunix, etc branded controllers, usually integrated onto the motherboard. This is really what kills SATA.

    I personally have a storage server with a 3ware card, with 4 of the new IBM/Hitach 7K250's, and it is quite fast. Then again, this is true hardware RAID, and as such it uses virtually no CPU.

    I had seen a great writeup on another forum, I'm thinking it was webservertalk, maybe I'm wrong. It was a very detailed back and forth between engineers that actually develop / design drives. Each drive has it's weak points, I wouldn't touch an IBM Ultrastar from the '2003 generation with a 10' pole, it really depends. You need to do the appropriate research before purchasing anything.

    SATA may suit your needs. For some people, paying 175/piece for a 36.7GB drive doesn't make sense; those are the people that will give up some performance to get the 400GB a SATA unit will offer.

    At any rate, to each his own. I personally can't stand using a SATA drive in my desktop, but when I've got 300GB+ of stuff, I'm not going to spend 1,000 to store it. I'll just run down to the local store and buy a couple (or just 1 nowadays) SATA drive(s).
    EuroVPS VPS Hosting - Virtual Private Servers | Web Hosting | Dedicated Servers
    Providing Reliable Plesk and cPanel Servers since 2004, now offering low priced Xen & VMware VPS in Amsterdam
    UK +44.203.355.6681 / Amsterdam +31.208.202.120

  12. #12
    You know, now that we're talking about this, does anyone have any experience with the Seagate 7200.7 drives?

    I just bought 1 x 200GB SATA as it was on sale, cheap, and haven't even opened the package yet. I don't even know what I'm going to do with it, I can't decide what it's purpose will be.. I guess that will depend much on the performance numbers it cranks out.

    I'm thinking of building a gaming box, I might use it for that.. Is this a good drive?
    EuroVPS VPS Hosting - Virtual Private Servers | Web Hosting | Dedicated Servers
    Providing Reliable Plesk and cPanel Servers since 2004, now offering low priced Xen & VMware VPS in Amsterdam
    UK +44.203.355.6681 / Amsterdam +31.208.202.120

  13. #13
    Join Date
    Sep 2003
    Posts
    1,915
    Take it back and go with a WD Raptor. Today I pulled a new Seagate 7200.7 out of my server and replaced it with a WD Raptor and the difference was unbelievable. Loaded FreeBSD in less then 5 minutes.

  14. #14
    Join Date
    Aug 2004
    Posts
    371

    Re: HD Performance Summary

    There is not a big difference between SCSI and SATA to justify the price difference, if you run database benchmarks, the difference is tiny, if you run HD transfer tests, the difference is not huge either. 10K RPM or 7200RPM, they are both slow.
    Seagate SATA drives can do NCQ. You pay $300 for a 300GB SATA, and pay $850 for a 300GB SCSI, that is $550 difference, and you can use that money to buy 2GB of ram. So if I want to choose between 8 300GB SCSI for $7200 or 8 300GB SATA for $2400 plus 16GB of ram, I will opt for the second solution.

    As for bandwith, SCSI drives share a bus, so bandwidth is limited by bus speed. In the case of SATA, each drive has a independent data path, so the combined bandwidth can be even larger than SCSI when multiple drives are used.

  15. #15
    Join Date
    Aug 2004
    Posts
    371
    See this page on comparing SCSI and SATA
    http://www.tweakers.net/reviews/557/29

    "The morale of the above story should be clear: no straight answer can be given to the question which interface performs the best in server applications. SATA configurations perform admirably well in file server and streaming media scenarios, while SCSI configurations (dependent on the specific type of adapter and harddisks) are king of the hill in database applications. "

  16. #16
    Join Date
    Aug 2004
    Posts
    371
    And this investigation shows that SATA faster in some cases

    http://www.pugetsystems.com/articles.php?id=19

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •