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Where are the High-Capacity SCSI Drives?

Posted by Cliff on from the has-ATA-surpassed-SCSI dept.

An anonymous reader asks: "Storage technology has really exploded in recent years, giving us ATA drives up to and exceeding 200-250 GB per drive. Why is it that SCSI drive technology has remained stagnant? I can't find a SCSI drive exceeding about a 146 GB capacity. Instead, businesses (and some individuals) wanting greater storage capacities are required to buy more drives which takes up more space, generates more heat, provides more points of failure, uses more electricity, etc. Why is this so?"

2 of 138 comments (clear)

  1. THE ANSWER by icandodat · · Score: 5, Informative

    This info is from an IBM Magnetic Storage Engineer. The reason is that the IDE market is a retail home market and very competitive. He said "If an IDE manufacturer can save 5 cents on a component he'll buy the cheaper one". The time from R and D to store shelf is less than a year. For SCSI drives on the other hand are primarily for servers and they have expensive components and are tested for a long time before they reach the market. The time from R and D to store shelf is about three years for SCSI. what was the bigest drive you could buy three years ago (ide)? Thats right about the same size as the biggest SCSI drive today. So ... what does this mean? IDE drives suck, they are cheap they are the zip lock bag of the storage industry. If you are going to grandmas with your data thats ok but if its going to the moon... buy tupperware, (SCSI).

  2. Too slow to be useful? by TheLink · · Score: 5, Informative

    Drive speeds haven't really gone up tremendously. Still too slow.

    Imagine you have a 1TB drive, but were stuck at a 100MB/sec max seq transfer rate. It takes you 2.7 hours to read/write the entire drive. And that's for _sequential_ access. Gets ugly for random seek.

    A similar speed 10TB drive will take you more than a day (27+ hours) to read sequentially.

    Before the point where it takes too long to read an entire single drive you might as well start using multiple drives to add capacity rather than having bigger drives.

    Taking too long is subjective, but I'd say this: how long can you make your boss/customer wait whilst you are restoring an entire disk image from backup? 27 hours or 2.7 hours? or 25 minutes?

    So 70GB would be about the limit if you have impatient users and bosses.

    Larger capacities are OK if they are to hold data that aren't important enough to be backed up, and don't require masses of data to be available quickly. Or you are doing mirroring and read speeds are important but write speeds aren't as important (but remember that restoring from backup = writing ;) ).

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