Re: [PATCH v5 0/2] skb_array: array based FIFO for skbs

From	Jason Wang <jasowang@redhat.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v5 0/2] skb_array: array based FIFO for skbs
Date	2016-05-31 04:30 +0200
Message-ID	<rEHBn-4Ct-11@gated-at.bofh.it> (permalink)
References	<rBVAR-4HP-9@gated-at.bofh.it> <rEs9j-2s5-11@gated-at.bofh.it> <rExsm-63s-19@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On 2016年05月30日 23:37, Michael S. Tsirkin wrote:
> On Mon, May 30, 2016 at 05:59:33PM +0800, Jason Wang wrote:
>>
>> On 2016年05月23日 18:43, Michael S. Tsirkin wrote:
>>> This is in response to the proposal by Jason to make tun
>>> rx packet queue lockless using a circular buffer.
>>> My testing seems to show that at least for the common usecase
>>> in networking, which isn't lockless, circular buffer
>>> with indices does not perform that well, because
>>> each index access causes a cache line to bounce between
>>> CPUs, and index access causes stalls due to the dependency.
>> I change tun to use skb array, looks like it can give about 5% more faster
>> than skb ring.
> OK and skb ring is 9% faster than the linked list, so together
> this is a 14% speedup?

Right.

>
>> And we usually don't need touch bhs during consume and produce (e.g for the
>> case of tun).
>>
>> Thanks
> Maybe I'll drop it in v6 then ...
> Could you post the full tun patchset please?
>

Since it needs no bh versions of produce/consume, maybe you can post v6 
first, then I can post the tun patches?

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[PATCH v5 0/2] skb_array: array based FIFO for skbs "Michael S. Tsirkin" <mst@redhat.com> - 2016-05-23 12:50 +0200
  Re: [PATCH v5 0/2] skb_array: array based FIFO for skbs Eric Dumazet <eric.dumazet@gmail.com> - 2016-05-23 15:40 +0200
    Re: [PATCH v5 0/2] skb_array: array based FIFO for skbs "Michael S. Tsirkin" <mst@redhat.com> - 2016-05-23 22:40 +0200
  Re: [PATCH v5 0/2] skb_array: array based FIFO for skbs Jason Wang <jasowang@redhat.com> - 2016-05-30 12:00 +0200
    Re: [PATCH v5 0/2] skb_array: array based FIFO for skbs "Michael S. Tsirkin" <mst@redhat.com> - 2016-05-30 17:40 +0200
      Re: [PATCH v5 0/2] skb_array: array based FIFO for skbs Jason Wang <jasowang@redhat.com> - 2016-05-31 04:30 +0200

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