raid3 is slow

[Ivan Voras]

Dag-Erling Smørgrav wrote:

> You don't seem to understand what the load averages mean.  They are
> the average number of runnable threads in the scheduler queue over the
> last one, five and fifteen seconds.  Certain workloads will drive up
> the load averages without consuming all available CPU time.  This is
> particularly the case for workloads where small chunks of data (e.g.
> RAID3 stripes) are passed around between multiple threads.

But, in his case the threads DO seem to consume much more CPU time than 
they should - especially the g_down thread. In this case, load avg ( as 
an approximation of real system load) is useful, and he's not concerned 
without cause.


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