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Date: Wed, 09 Oct 2013 20:09:00 +0200
From: Hans de Goede <hdegoede@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] main-loop: Don't lock starve io-threads
 when main_loop_tlg has pending events
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-devel@nongnu.org, Alex Bligh <alex@alex.org.uk>

Hi,

On 10/09/2013 04:37 PM, Paolo Bonzini wrote:
> Il 09/10/2013 14:58, Hans de Goede ha scritto:
>>
>>
>> I still think we should add my patch in some form, since the lock
>> starvation
>> caused by timers set to expire in the past could still happen in other
>> cases,
>> esp for timer users who take a time stamp once and then add incremental
>> values to trigger the next run, these can get behind quite a bit if there
>> are latency spikes, and we don't wont to run without ever releasing the
>> lock while these are catching up.
>
> I agree.  Do you also agree that the equivalent workaround, before
> Alex's patch, was MIN_REARM_TIMER_NS (and thus 250 microseconds)?

I think I agree :)

Regards,

Hans