ExtremeRAID with NV cache) and "dumb" (3ware 6410) ld providers.
Instead, use the default buffer queue policy.
With the 3ware adapter, using the read priority strategy instead of FCFS,
for three extractions of pkgsrc, took 329 seconds instead of 331 -- but
with a dramatic improvement in perceived system response (latency for
I/O outside the main stream).
With the Mylex adapter, the improvement was dramatic: using read priority
instead of FCFS yielded an improvement from 381 seconds to 135 seconds!
There was a less-noticeable improvement in perceived latency as well.
The other disk drivers currently hard-wired to FCFS or another policy
should probably be changed as well.
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