Subject: Re: DEV_B_SIZE
To: Steve Byan <firstname.lastname@example.org>
From: None <email@example.com>
Date: 01/31/2003 20:23:52
In message <1010FEB6-354F-11D7-B26B-00306548867E@maxtor.com>, Steve Byan writes
>> Not broken any worse than because of write-caching.
>Agreed, but IDEMA is proposing to do this to SCSI drives, too.
We've seen broken caching on SCSI as well, but not recently I think :-)
>But if someone were to plug a new 4K-block disk into a system compiled
>to use 512 byte block disks, and the SCSI interface were faked to make
>it appear that the disk could read and write 512-byte blocks, then what
>happens? IDEMA's notion is that faking 512-byte logical size is good
>enough to get new disks to work in systems running legacy code. My fear
>is that it is not so simple.
If plug a 4k sector disk into a system which doesn't know how to find
out that the drive really is 4k sectors, then you will increase the
window for lossage.
>> The thing we really need is working tagged-queing...
>Since I believe tagged-queuing works in SCSI, I assume you are asking
>for it in ATA? Or is there some feature missing from SCSI
>tagged-queuing that you'd like to see?
Yes, I was talking ATA there.
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