From: Eran Rom <eranr@il.ibm.com>
To: kvm@vger.kernel.org
Subject: Re: guest gettimeofday behavior
Date: Tue, 7 Jul 2009 09:58:46 +0000 (UTC) [thread overview]
Message-ID: <loom.20090707T081402-628@post.gmane.org> (raw)
In-Reply-To: loom.20090706T081604-11@post.gmane.org
Eran Rom <eranr <at> il.ibm.com> writes:
>
> Eran Rom <eranr <at> il.ibm.com> writes:
>
> Still getting a misbehaving clock:
> guest uses kvmclock with kernel 2.6.27
> host kernel is 2.6.27 with kvm-qemu-87 & kvm-kmod-87
>
> getting:
> ...
> now = 2128043797
> now = 2138048010
> now = 18446744071562636328
>
Below is the exact code used.
Also, I use a script in the host to run this code in a loop for 5 minutes, each
time in a newly launched guest. This happens on average once every 10 executions.
Thanks very much,
Eran
#include <sys/time.h>
#include <time.h>
int main(int argc, char **argv)
{
int seconds;
unsigned long long now, goal;
struct timeval time1, time2;
if (argc != 2)
return;
seconds = atoi(argv[1]);
gettimeofday(&time1, NULL);
now = ((time1.tv_sec) * 1000000) + time1.tv_usec;
goal = now + (seconds * 1000000);
while (now < goal) {
sleep(10);
gettimeofday(&time2, NULL);
now = (time2.tv_sec * 1000000) + time2.tv_usec;
}
}
next prev parent reply other threads:[~2009-07-07 9:58 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-06-25 13:25 guest gettimeofday behavior Eran Rom
2009-06-28 8:58 ` Dor Laor
2009-06-29 19:11 ` Eran Rom
2009-06-30 6:54 ` Avi Kivity
2009-06-30 7:48 ` Eran Rom
2009-07-06 8:24 ` Eran Rom
2009-07-07 9:58 ` Eran Rom [this message]
2009-07-07 20:12 ` Marcelo Tosatti
2009-07-08 11:51 ` Glauber Costa
2009-07-08 14:07 ` Eran Rom
2009-07-13 7:55 ` Eran Rom
2009-07-16 6:24 ` Eran Rom
2009-06-28 10:45 ` Avi Kivity
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