Re: [Tracker] Indexers comparison

[Joe Shaw <joeshaw novell com>]

Hi,

> choosing another scheduling policy (like sched_batch) is a
> bit better, as a sched_batch process will use 0% cpu in presence of
> another process trying to get 100% cpu.

I looked into this today, and this isn't how the SCHED_BATCH policy
works on Linux (at least with 2.6.20).  Indeed doing so would cause an
issue with priority inversion, since a blocked process could hold some
resource while another process spun.

SCHED_BATCH simply drops the sleep interval calculation, which
determines the bonus (between -5 and +5) on top of your nice value, and
automatically gives your process a -5 bonus.

Joe