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From: Anthony Liguori <aliguori@us.ibm.com>
To: Avi Kivity <avi@redhat.com>
Cc: kvm@vger.kernel.org
Subject: Re: [PATCH 18/21] Remove host_alarm_timer hacks.
Date: Thu, 30 Apr 2009 08:37:01 -0500	[thread overview]
Message-ID: <49F9A97D.7050004@us.ibm.com> (raw)
In-Reply-To: <49F9A6BA.5040702@redhat.com>

Avi Kivity wrote:
> Anthony Liguori wrote:
>> In modern KVM, the IO thread is capable of interrupting the CPU 
>> whenever it needs to process IO.  Therefore this "problem" no longer 
>> exists.
>>
>
> It would still be good to verify that the problem no longer exists.  
> This is not a cosmetic change; some testing is needed to verify it 
> doesn't introduce new latencies.
>

N.B. dynticks is the preferred timer in QEMU on Linux.  To even hit this 
code path, you'd have to use an explicit -clock hpet or -clock rtc.  I 
don't have an hpet on my laptop and -clock rtc boots just as fast as it 
did before.

Do we really care about optimizing latency with -clock rtc though?

-- 
Regards,

Anthony Liguori


  reply	other threads:[~2009-04-30 13:37 UTC|newest]

Thread overview: 53+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-04-29 21:20 [PATCH 0/21] Remove merge artifacts from qemu-kvm Anthony Liguori
2009-04-29 21:20 ` [PATCH 01/21] Remove memalign call for guess_disk_lchs Anthony Liguori
2009-04-29 21:20 ` [PATCH 02/21] Remove devfn from BlockDriverState Anthony Liguori
2009-04-29 21:20 ` [PATCH 03/21] Remove use of signalfd in block-raw-posix.c Anthony Liguori
2009-04-30  9:28   ` Avi Kivity
2009-04-30 12:54     ` Anthony Liguori
2009-04-30 13:05       ` Avi Kivity
2009-04-30 13:28         ` Anthony Liguori
2009-04-30 13:36           ` Avi Kivity
2009-05-03 16:48             ` Avi Kivity
2009-04-29 21:20 ` [PATCH 04/21] Remove stray whitespace Anthony Liguori
2009-04-29 21:20 ` [PATCH 05/21] Remove extra call to kvm_cpu_exec() Anthony Liguori
2009-04-29 21:20 ` [PATCH 06/21] Remove dead functions from cutils Anthony Liguori
2009-04-29 21:20 ` [PATCH 07/21] Remove dead macros likely/unlikely in exec.c Anthony Liguori
2009-04-29 21:20 ` [PATCH 08/21] Remove leftovers in device-hotplug.c Anthony Liguori
2009-04-29 21:20 ` [PATCH 09/21] Remove unnecessary setting of cmos smp_cpu count Anthony Liguori
2009-04-29 21:20 ` [PATCH 10/21] Remove IBM copyright in unmodified file in upstream Anthony Liguori
2009-04-29 21:38   ` Hollis Blanchard
2009-04-29 21:20 ` [PATCH 11/21] Remove unused variables in vga.c Anthony Liguori
2009-04-30  9:33   ` Avi Kivity
2009-04-30 13:09     ` Anthony Liguori
2009-04-29 21:20 ` [PATCH 12/21] Remove odd hack " Anthony Liguori
2009-04-30  9:39   ` Avi Kivity
2009-04-29 21:20 ` [PATCH 13/21] Remove virtio-console PIF change Anthony Liguori
2009-04-30  9:40   ` Avi Kivity
2009-04-29 21:20 ` [PATCH 14/21] Remove -cpu-vendor-string Anthony Liguori
2009-04-30  9:41   ` Avi Kivity
2009-04-30 13:10     ` Anthony Liguori
2009-04-30 13:16       ` Avi Kivity
2009-04-30 13:26         ` Anthony Liguori
2009-04-30 13:33           ` Avi Kivity
2009-04-29 21:20 ` [PATCH 15/21] Remove defined(TARGET_X86_64) Anthony Liguori
2009-04-29 21:20 ` [PATCH 16/21] Remove clean rule change Anthony Liguori
2009-04-30  9:42   ` Avi Kivity
2009-04-30 15:10     ` Hollis Blanchard
2009-04-30 15:13       ` Avi Kivity
2009-04-29 21:20 ` [PATCH 17/21] Remove #define __user in usb-linux.c Anthony Liguori
2009-04-30  9:43   ` Avi Kivity
2009-04-30 13:11     ` Anthony Liguori
2009-04-30 13:17       ` Avi Kivity
2009-04-30 13:20         ` Anthony Liguori
2009-04-29 21:20 ` [PATCH 18/21] Remove host_alarm_timer hacks Anthony Liguori
2009-04-30  9:44   ` Avi Kivity
2009-04-30 13:19     ` Anthony Liguori
2009-04-30 13:25       ` Avi Kivity
2009-04-30 13:37         ` Anthony Liguori [this message]
2009-04-30 15:46           ` Avi Kivity
2009-04-30 15:49             ` Anthony Liguori
2009-04-30 15:53               ` Avi Kivity
2009-04-29 21:20 ` [PATCH 19/21] Use QEMU_PKGVERSION to declare kvm-devel Anthony Liguori
2009-04-29 21:20 ` [PATCH 20/21] Get rid of qemu_get_launch_info() Anthony Liguori
2009-04-29 21:20 ` [PATCH 21/21] Leave upstream QEMU comments intact Anthony Liguori
2009-04-30  9:50 ` [PATCH 0/21] Remove merge artifacts from qemu-kvm Avi Kivity

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