Date: Sat, 11 Dec 2010 22:33:33 +0000 (UTC) From: Colin Percival <cperciva@FreeBSD.org> To: cvs-src-old@freebsd.org Subject: cvs commit: src/sys/i386/xen clock.c Message-ID: <201012112233.oBBMXtkj060417@repoman.freebsd.org>
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cperciva 2010-12-11 22:33:33 UTC
FreeBSD src repository
Modified files:
sys/i386/xen clock.c
Log:
SVN rev 216385 on 2010-12-11 22:33:33Z by cperciva
Reduce the Xen timecounter from 1GHz to 2^-9 GHz, thereby increasing the
timecounter period from 2^32 ns (~4.3s) to 2^41 ns (~36m39s). Some time
sharing systems can skip clock interrupts for a few seconds when under
load (e.g., if we've recently used more than our fair share of CPU and
someone else wants a burst of CPU) and we were losing time in quanta of
2^32 ns due to timecounter wrapping.
Increasing the timecounter period up to 2^41 ns is definitely overkill,
but we still have microsecond timecounter precision, and anyone using
paravirtualized hardware when they need submicrosecond timing is crazy.
Revision Changes Path
1.15 +3 -2 src/sys/i386/xen/clock.c
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