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Serial SCSI Standard Coming Soon

Posted by michael on from the scuzzy-wuzzy dept.

rchatterjee writes "SCSI is very close to joining ATA in leaving a parallel interface design behind in favor of serial one. Serial attached SCSI, as the standard will be known, is expected to be ratified sometime in the second quarter of this year according to this article at Computerworld. Hard drive manufacturers Seagate and Maxtor have already said that they will have drives conforming to the new standard shipping by the end of the year. The new standard will shatter the current SCSI throughput limit of 320 megabit/sec with a starting maximum throughput of 3 gigabit/sec. But before this thread turns into a SCSI fanboy vs. ATA fanboy flame war this other article states that Serial Attached SCSI will be compatible with SATA drives so you can have the best of both worlds."

4 of 328 comments (clear)

  1. Ok, So I've noticed a couple of corrections. by taliver · · Score: 5, Insightful

    If the article meant to say 3GBytes, then how in the world will the PCI *at 64bits and 133MHz, it's 1 GB/sec transfer) bus keep up? Or even RAMBUS memory, which, here says it has a bandwidth of 4.2GB/sec. (So, kinda means you couldn't have more than one SCSI system at a time and get full bandwidth from both.) Now, if you may have to have memory banks for each SCSI component... ick.

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  2. good performance.. but at what price? by thadeusPawlickiROX · · Score: 5, Insightful

    Sure, this definately looks like it could be a great setup: fast, and compatable on multiple systems. But how much will this technology cost? Standard, run of the mill IDE hard drives are about a dollar per Gig. Regular SCSI is a few times higher, especially as drives grow in size. This will be a great advantage if the price range is in the middle of the range, but I doubt that. Now, this won't matter to those with plenty of money to burn on their servers, but would that added price be worth the new types of hard drives? I still don't even see a huge advantage to going Serial ATA right now, so this seemingly good idea could just be another good idea that won't pan out for most users.

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    1. Re:good performance.. but at what price? by Magus311X · · Score: 4, Insightful

      Not just fast, but reliable.

      Not to say that ATA disks aren't reliable, but the components that are used in ATA disks are typically those that were outside the absurdly strict tolerances that are required for "enterprise-class" drives.

      And yes, when it comes to speed, SCSI tends to rule the roost. Not only because you can throw 320MB/s down each individual channel, but you can toss enough devices on that channel to keep that overall speed sustained over longer periods of time.

      Drives have very high burst speeds, but have it do lots of random data access constantly and watch speeds plummet. That's why a 10-disk striped array (with another 10-disks to mirror if you require redundancy, likely on another channel) tends to kick considerable ass. Because even if you're only sustaining say... 10MB/sec per disk, it's now 100MB/sec over the channel.

      ATA storage is definitely cheap. If all that is required is just LOTS of storage, and performance and reliability isn't really critical, ATA is a pretty good choice. Of course then you could use robotic tape libraries as well.

      SCSI also really ruled the server rooms because those expensive servers and storage systems simply didn't have ATA support. Period.

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  3. Re:Mbit != MByte by Cramer · · Score: 4, Insightful

    That doesn't matter. Almost everything else in the post is in error. SCSI already has a serial interface standard (and has for a very long time.) -- ever heard of Fibre Channel or Firewire? SATA and SSCSI compatiblity? F***ing duh! What do you think ATAPI is? The SCSI command protocol moving in packets across an IDE physical interface.

    I don't know what stupid scheme they are trying to create here -- interface-wise. SATA is a point-to-point configuration. SCSI has always been a bus configuration. If they go the p-t-p route, then it depends on the controller to be able to support the device on the other end -- SCSI crossing the pyhical interface or IDE/ATA/ATAPI crossing it. (Think parallel port ethernet dongle.) I'll have a hard time accepting p-t-p SCSI.

    If they want to make SCSI more attractive, they should stop significantly over charging for the technology. They can bulk test "desktop" SCSI drives just as cheaply as IDE drives. They all use the same servo assemblies -- and in some cases, the same basic interface logic (obviously with different microcode.)