Adaptec 1542 Kernel tuning with 386/ix

[Russ Poffenberger]

In article <PCG.90Jul5152829 at odin.cs.aber.ac.uk> pcg at cs.aber.ac.uk (Piercarlo Grandi) writes:
>
>In article <1990Jul04.123903.3204 at nstar.uucp> larry at nstar.uucp (Larry
>Snyder) writes:
>
>   behm at zds-ux.UUCP (Brett Behm) writes:
>
>   >I really do not know what to make of these results.
>
>   I don't either.  In all cases the tests were executed on the same
>   location on the disk - with NOTHING else running..
>
>But you don't teel us the crucial details -- did you read from the raw
>device, the block device, or from the filesystem? In the latter two
>cases, how did you defeat the read-aheading. or ensured it was used, and
>in the last ase, did you unmount/remount the filesystem before each read
>to be sure to defeat the caching?
>
>All over I see transfer rates around 300K per second. If they are thru
>the filesystem it is not too bad, but I had expected better from
>AHA1542, HPDD, and FFS. Something more like 5000-600 KB/sec.

I can get 1.3Mbytes / sec from an AHA1542B with a CDC Wren IV running dos. This
is straight disk performance, not cached. Reads and writes are about the same.


Russ Poffenberger               DOMAIN: poffen at sj.ate.slb.com
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