From mboxrd@z Thu Jan  1 00:00:00 1970
From: Markus Oberrauter <oberrauter@funatics.de>
Subject: clock_gettime monotonic & realtime swapped?
Date: Fri, 28 May 2010 17:20:47 +0200
Message-ID: <4BFFDF4F.6020609@funatics.de>
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Hi all,

we are currently having a lot of problems with our virtualized server (=20
time jumps 73 minutes backwards ).
I tried to find out how virtualization affects the clock of the client,=20
so I=C2=B4ve downloaded the current xen source ( xen-4.0.0 ) and searched=
 all=20
files for "clock".

I don=C2=B4t think that this will be the cause of our problems here, but =
I=20
found an interesting switch - case statement in extras \ mini-os \ lib \=20
sys.c.

int clock_gettime(clockid_t clk_id, struct timespec *tp)
{
...
case CLOCK_MONOTONIC:
gettimeofday(&tv, NULL);
break;

case CLOCK_REALTIME:
uint64_t nsec =3D monotonic_clock();
break;
...
}

I had expected that CLOCK_MONOTONIC returns monotonic_clock and=20
CLOCK_REALTIME returns gettimeofday().
I hope this was the right place to post this information.

Greetings,
Markus Oberrauter