From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jamal Hadi Salim <jhs@mojatatu.com>
Subject: Re: [PATCH net-next 6/6] net_sched: act: remove spinlock in fast
 path
Date: Fri, 03 Jul 2015 07:25:43 -0400
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Cc: Eric Dumazet <edumazet@google.com>,
	"David S. Miller" <davem@davemloft.net>,
	netdev <netdev@vger.kernel.org>,
	Alexei Starovoitov <ast@plumgrid.com>,
	Eric Dumazet <edumazet@gmail.com>
To: Eric Dumazet <eric.dumazet@gmail.com>,
	John Fastabend <john.fastabend@gmail.com>
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On 07/02/15 16:59, Eric Dumazet wrote:
> On Thu, 2015-07-02 at 09:35 -0700, John Fastabend wrote:

>
> Point is to not dirty cache line for every packet ?
>
> Doing the test means we attempt dirtying only ~HZ times per second,
> which really matters to handle millions of packets per second.
>
> My tests show a good enough performance, not sure we want a percpu thing
> for this lastuse field.
>

Does it harm to always set gact->tcf_tm.lastuse ?

cheers,
jamal