queue depth

[Carlos Carvalho]

Xia Hao (axis at prodigychina.com) wrote on 5 August 1998 12:43:
 >  i'm using Linux 2.0.35, no scsi patch yet.  i have one Seagate 32550W
 >2.1G HD and 4 Seagate 32171W all connected to a AHA2940UW adapter.  I'm
 >just wondering what the individual queue depths should be for each of
 >these disks to achieve maximum random access performance while ensuring
 >system stablity.  Any clues?

I'd suggest something like 24. You have however many disks on a single
controller... You can also try 32. Leonard Zubkoff says more than this
is counter-productive.

There's however a problem with queueing in certain circumstances. I
have 3 Cheetah's in two controllers, plus some other disks, and two of
the Cheetah don't get any queue depth :-(

Carlos

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