From: Zhang Haoyu <ahzhanghaoyu@gmail.com>
To: Wanpeng Li <kernellwp@gmail.com>, kvm <kvm@vger.kernel.org>,
"qemu-devel@nongnu.org Developers" <qemu-devel@nongnu.org>
Subject: Re: [question] Is there a plan to introduce a unified co-scheduling mechanism to CFS ?
Date: Fri, 10 Oct 2014 20:00:46 +0800 [thread overview]
Message-ID: <5437CA6E.2000802@gmail.com> (raw)
In-Reply-To: <5437C6A2.3020908@gmail.com>
>> Hi,
>>
>> Is it worthy to introduce a unified co-scheduling mechanism to CFS ?
>> Because multiple cooperating threads or tasks frequently synchronize
with each other,
>> not executing them concurrently would only increase the latency of
synchronization.
>> For example, a thread blocking in spinlock to waiting for another
thread to release the same spinlock
>> might reduce its waiting time by being executed concurrently with
the thread which hold the same spinlock.
>> In virtualization scenario, multiple vcpus (which belong to the same
vm) co-scheduling is more desired
>> when several cooperating threads/task is running in guest.
>>
>> Is there a plane for this work?
>
> Please refer to gang scheduler.
>
Is there a mechanism to dynamically detect which vcpus belong to the
same gang?
Maybe a cooperative degree can be used to decide the threshold of which
vcpus belong to the same gang, just a wild thought.
> Regards,
> Wanpeng Li
>>
>> Thanks,
>> Zhang Haoyu
WARNING: multiple messages have this Message-ID (diff)
From: Zhang Haoyu <ahzhanghaoyu@gmail.com>
To: Wanpeng Li <kernellwp@gmail.com>, kvm <kvm@vger.kernel.org>,
"qemu-devel@nongnu.org Developers" <qemu-devel@nongnu.org>
Subject: Re: [Qemu-devel] [question] Is there a plan to introduce a unified co-scheduling mechanism to CFS ?
Date: Fri, 10 Oct 2014 20:00:46 +0800 [thread overview]
Message-ID: <5437CA6E.2000802@gmail.com> (raw)
In-Reply-To: <5437C6A2.3020908@gmail.com>
>> Hi,
>>
>> Is it worthy to introduce a unified co-scheduling mechanism to CFS ?
>> Because multiple cooperating threads or tasks frequently synchronize
with each other,
>> not executing them concurrently would only increase the latency of
synchronization.
>> For example, a thread blocking in spinlock to waiting for another
thread to release the same spinlock
>> might reduce its waiting time by being executed concurrently with
the thread which hold the same spinlock.
>> In virtualization scenario, multiple vcpus (which belong to the same
vm) co-scheduling is more desired
>> when several cooperating threads/task is running in guest.
>>
>> Is there a plane for this work?
>
> Please refer to gang scheduler.
>
Is there a mechanism to dynamically detect which vcpus belong to the
same gang?
Maybe a cooperative degree can be used to decide the threshold of which
vcpus belong to the same gang, just a wild thought.
> Regards,
> Wanpeng Li
>>
>> Thanks,
>> Zhang Haoyu
next prev parent reply other threads:[~2014-10-10 12:01 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-10 11:37 [question] Is there a plan to introduce a unified co-scheduling mechanism to CFS ? Zhang Haoyu
2014-10-10 11:37 ` [Qemu-devel] " Zhang Haoyu
2014-10-10 11:44 ` Wanpeng Li
2014-10-10 11:44 ` [Qemu-devel] " Wanpeng Li
2014-10-10 12:00 ` Zhang Haoyu [this message]
2014-10-10 12:00 ` Zhang Haoyu
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