Date: Mon, 24 Apr 2017 14:08:35 +0200
From: Florian Westphal <fw@strlen.de>
To: Andrey Konovalov <andreyknvl@google.com>
Cc: Florian Westphal <fw@strlen.de>, Eric Dumazet <edumazet@google.com>,
        Cong Wang <xiyou.wangcong@gmail.com>, netdev <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Dmitry Vyukov <dvyukov@google.com>, Kostya Serebryany <kcc@google.com>,
        syzkaller <syzkaller@googlegroups.com>
Subject: Re: net: cleanup_net is slow
Message-ID: <20170424120835.GA20444@breakpoint.cc>
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Andrey Konovalov <andreyknvl@google.com> wrote:
> On Fri, Apr 21, 2017 at 9:45 PM, Florian Westphal <fw@strlen.de> wrote:
> > Florian Westphal <fw@strlen.de> wrote:
> >> Indeed.  Setting net.netfilter.nf_conntrack_default_on=0 cuts time
> >> cleanup time by 2/3 ...
> >>
> >> nf unregister is way too happy to issue synchronize_net(), I'll work on
> >> a fix.
> >
> > I'll test this patch as a start.  Maybe we can also leverage exit_batch
> > more on netfilter side.
> 
> Hi Florian,
> 
> Your patch improves fuzzing speed at least twice, which is a great start!

Great.  I'll try to push the patches i have to nf-next ASAP.