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From: Gerd Hoffmann <kraxel@redhat.com>
To: Avi Kivity <avi@redhat.com>
Cc: seabios@seabios.org, kvm@vger.kernel.org
Subject: Re: [PATCH] tsc: use kvmclock for calibration
Date: Thu, 09 Aug 2012 16:18:32 +0200	[thread overview]
Message-ID: <5023C6B8.4090805@redhat.com> (raw)
In-Reply-To: <5023C2BE.5070702@redhat.com>

  Hi,

>> So what do you suggest?  The options I see are:
>>
>>   (1) Use this patch (with alignment issue fixed of course).
>>   (2) Do a full kvmclock implementation.  Feels a bit like overkill.
>>   (3) SeaBIOS can fallback to the PIT for timing on machines which
>>       have no TSC.  We could do that too in case we detect kvm ...
> 
> What sort of timeouts are these?  If seconds, maybe the rtc would be best.

All sorts of timeouts, from a few miliseconds to seconds.

The problematic ones are the longer timeouts, which wait for I/O stuff
like disk reads complete.  The stuff with smaller timeouts (like waiting
for AHCI link become ready) tend to finish instantly in kvm.

cheers,
  Gerd

  parent reply	other threads:[~2012-08-09 14:18 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-08-09 11:57 [PATCH] tsc: use kvmclock for calibration Gerd Hoffmann
2012-08-09 12:53 ` Avi Kivity
2012-08-09 13:25   ` [SeaBIOS] " Fred .
2012-08-09 13:57   ` Gerd Hoffmann
2012-08-09 14:01     ` Avi Kivity
2012-08-09 14:05       ` Avi Kivity
2012-08-09 14:12         ` Gerd Hoffmann
2012-08-09 14:17           ` Avi Kivity
2012-08-09 14:18       ` Gerd Hoffmann [this message]
2012-08-09 14:20         ` Avi Kivity
2012-08-09 19:02           ` Marcelo Tosatti
2012-08-12 10:56             ` Avi Kivity
2012-08-09 19:09       ` Marcelo Tosatti
2012-08-10  7:18         ` Gleb Natapov
2012-08-10  7:30           ` Gleb Natapov
2012-08-10  8:10         ` Gerd Hoffmann
2012-08-10 21:26           ` Marcelo Tosatti
2012-08-13 10:37             ` Gerd Hoffmann
2012-08-13 10:46               ` Gleb Natapov
2012-08-13 12:55                 ` [SeaBIOS] " Fred .
2012-08-12  9:00           ` Avi Kivity
2012-08-09 18:59   ` Marcelo Tosatti
2012-08-12  9:01     ` Avi Kivity

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