netdev - Re: [PATCH RFC 0/7] add socket to netdev page frag recycling support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 18 Aug 2021 16:05:52 -0600
From:   David Ahern <dsahern@...il.com>
To:     Yunsheng Lin <linyunsheng@...wei.com>, davem@...emloft.net,
        kuba@...nel.org
Cc:     alexander.duyck@...il.com, linux@...linux.org.uk, mw@...ihalf.com,
        linuxarm@...neuler.org, yisen.zhuang@...wei.com,
        salil.mehta@...wei.com, thomas.petazzoni@...tlin.com,
        hawk@...nel.org, ilias.apalodimas@...aro.org, ast@...nel.org,
        daniel@...earbox.net, john.fastabend@...il.com,
        akpm@...ux-foundation.org, peterz@...radead.org, will@...nel.org,
        willy@...radead.org, vbabka@...e.cz, fenghua.yu@...el.com,
        guro@...com, peterx@...hat.com, feng.tang@...el.com, jgg@...pe.ca,
        mcroce@...rosoft.com, hughd@...gle.com, jonathan.lemon@...il.com,
        alobakin@...me, willemb@...gle.com, wenxu@...oud.cn,
        cong.wang@...edance.com, haokexin@...il.com, nogikh@...gle.com,
        elver@...gle.com, yhs@...com, kpsingh@...nel.org,
        andrii@...nel.org, kafai@...com, songliubraving@...com,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        bpf@...r.kernel.org, chenhao288@...ilicon.com, edumazet@...gle.com,
        yoshfuji@...ux-ipv6.org, dsahern@...nel.org, memxor@...il.com,
        linux@...pel-privat.de, atenart@...nel.org, weiwan@...gle.com,
        ap420073@...il.com, arnd@...db.de,
        mathew.j.martineau@...ux.intel.com, aahringo@...hat.com,
        ceggers@...i.de, yangbo.lu@....com, fw@...len.de,
        xiangxia.m.yue@...il.com, linmiaohe@...wei.com
Subject: Re: [PATCH RFC 0/7] add socket to netdev page frag recycling support

On 8/17/21 9:32 PM, Yunsheng Lin wrote:
> This patchset adds the socket to netdev page frag recycling
> support based on the busy polling and page pool infrastructure.
> 
> The profermance improve from 30Gbit to 41Gbit for one thread iperf
> tcp flow, and the CPU usages decreases about 20% for four threads
> iperf flow with 100Gb line speed in IOMMU strict mode.
> 
> The profermance improve about 2.5% for one thread iperf tcp flow
> in IOMMU passthrough mode.
> 

Details about the test setup? cpu model, mtu, any other relevant changes
/ settings.

How does that performance improvement compare with using the Tx ZC API?
At 1500 MTU I see a CPU drop on the Tx side from 80% to 20% with the ZC
API and ~10% increase in throughput. Bumping the MTU to 3300 and
performance with the ZC API is 2x the current model with 1/2 the cpu.

Epyc 7502, ConnectX-6, IOMMU off.

In short, it seems like improving the Tx ZC API is the better path
forward than per-socket page pools.