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Date: Sun, 2 Jan 2011 11:20:11 GMT
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To: freebsd-xen@FreeBSD.org
From: Colin Percival <cperciva@freebsd.org>
Cc: 
Subject: Re: kern/153620: Xen guest system clock drifts in AWS EC2 (FreeBSD
 9.0-CURRENT i386 T1-micro)
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The following reply was made to PR kern/153620; it has been noted by GNATS.

From: Colin Percival <cperciva@freebsd.org>
To: bug-followup@FreeBSD.org, fbsd-9.0-aws-ec2-1293964000@holmberg.to
Cc:  
Subject: Re: kern/153620: Xen guest system clock drifts in AWS EC2 (FreeBSD
 9.0-CURRENT i386 T1-micro)
Date: Sun, 02 Jan 2011 03:16:52 -0800

 This is interesting -- I thought I had squashed all the clock drift bugs.
 
 Can you tell me:
 1. Did the clock run ahead, or behind?
 2. Can you reproduce this?
 3. Did the clock _drift_, or _jump_?
 
 The 2200 seconds mentioned is almost exactly the 2^41 ns period of the Xen
 timecounter, so if the clock jumped it's probably safe to guess that it's
 involved somehow...
 
 -- 
 Colin Percival
 Security Officer, FreeBSD | freebsd.org | The power to serve
 Founder / author, Tarsnap | tarsnap.com | Online backups for the truly paranoid