>  Quantum is the only manufacturer to offer true zero latency reads (they did
>  their cache right).

>I always thought that disk drive based caches were counter-productive if
>you're running an os with its own disk cache, as NetBSD has.  Is that wrong?
>Has anyone ever measured the effect of a drive based cache on BSD
>performance?

There was a very detailed paper written on this a few years back.
Sorry, I don't remember where I found it.  It was tested on HP
workstations.  I don't remember if they used HP/UX or some other Unix
(like 4.3 or 4.4BSD).

They concluded that drive-based caches were a significant help.

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  Michael L. VanLoon                                 michaelv@HeadCandy.com
        --<  Free your mind and your machine -- NetBSD free un*x  >--
    NetBSD working ports: 386+PC, Mac 68k, Amiga, Atari 68k, HP300, Sun3,
        Sun4/4c/4m, DEC MIPS, DEC Alpha, PC532, VAX, MVME68k, arm32...
    NetBSD ports in progress: PICA, others...

   Roll your own Internet access -- Seattle People's Internet cooperative.
                  If you're in the Seattle area, ask me how.
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