From: Paul Brook <paul@codesourcery.com>
To: qemu-devel@nongnu.org
Cc: Gleb Natapov <gleb@redhat.com>
Subject: Re: [Qemu-devel] [RESEND][PATCH 0/3] Fix guest time drift under heavy load.
Date: Thu, 6 Nov 2008 15:24:42 +0100 [thread overview]
Message-ID: <200811061424.43689.paul@codesourcery.com> (raw)
In-Reply-To: <4912FAE5.9010100@codemonkey.ws>
> You see time drift with 100hz timers in the guest?? That makes very
> little sense as even without hr timers, the host should have no problem
> delivering a 10ms timer.
If your host has HZ=100 and no HR timers than a 10ms interval is fairly
borderline, and it's not that hard to end up missing an interrupt, especially
under heavy load.
If part of qemu gets swapped out then all bets are off, and you can easily
stall for significant fractions of a second. No amount of host high
resolution time support will help you there.
Paul
next prev parent reply other threads:[~2008-11-06 14:24 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-10-29 15:22 [Qemu-devel] [RESEND][PATCH 0/3] Fix guest time drift under heavy load Gleb Natapov
2008-10-29 15:22 ` [Qemu-devel] [PATCH 1/3] Change qemu_set_irq() to return status information Gleb Natapov
2008-10-29 15:22 ` [Qemu-devel] [PATCH 2/3] Fix time drift problem under high load when PIT is in use Gleb Natapov
2008-10-29 15:22 ` [Qemu-devel] [PATCH 3/3] Fix time drift problem under high load when RTC " Gleb Natapov
2008-11-05 12:46 ` Dor Laor
2008-10-31 19:17 ` [Qemu-devel] [RESEND][PATCH 0/3] Fix guest time drift under heavy load Anthony Liguori
2008-11-02 13:04 ` Gleb Natapov
2008-11-05 12:45 ` Dor Laor
2008-11-05 15:48 ` andrzej zaborowski
2008-11-05 16:33 ` Anthony Liguori
2008-11-06 7:16 ` Gleb Natapov
2008-11-06 9:37 ` andrzej zaborowski
2008-11-06 10:08 ` Gleb Natapov
2008-11-06 13:21 ` andrzej zaborowski
2008-11-06 14:18 ` Gleb Natapov
2008-11-06 14:35 ` andrzej zaborowski
2008-11-06 15:04 ` Gleb Natapov
2008-11-06 15:41 ` Anthony Liguori
2008-11-07 23:18 ` andrzej zaborowski
2008-11-08 8:23 ` Gleb Natapov
2008-11-06 13:44 ` Paul Brook
2008-11-05 17:43 ` Gleb Natapov
2008-11-06 17:28 ` David S. Ahern
2008-11-05 16:43 ` Anthony Liguori
2008-11-06 3:55 ` Jamie Lokier
2008-11-06 8:12 ` Gleb Natapov
2008-11-06 14:10 ` Anthony Liguori
2008-11-06 14:24 ` Paul Brook [this message]
2008-11-06 14:40 ` Anthony Liguori
2008-11-06 14:51 ` Gleb Natapov
2008-11-06 15:37 ` Anthony Liguori
2008-11-08 8:36 ` Gleb Natapov
2008-11-08 22:14 ` Dor Laor
2008-11-09 7:40 ` Gleb Natapov
2008-11-09 16:38 ` Anthony Liguori
2008-11-09 21:00 ` Avi Kivity
2008-11-09 16:36 ` Anthony Liguori
2008-11-10 14:37 ` Gleb Natapov
2008-11-10 15:24 ` Anthony Liguori
2008-11-10 15:29 ` Gleb Natapov
2008-11-10 15:46 ` Anthony Liguori
2008-11-10 15:51 ` Gleb Natapov
2008-11-11 14:43 ` Gleb Natapov
2008-11-11 17:26 ` Anthony Liguori
2008-11-11 20:17 ` Anthony Liguori
2008-11-12 11:42 ` Gleb Natapov
2008-11-12 11:54 ` Glauber Costa
2008-11-12 12:38 ` Dor Laor
2008-11-06 3:41 ` Jamie Lokier
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