netdev - Re: small RPS cache for fragments?

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:	Tue, 17 May 2011 16:47:32 -0400 (EDT)
From:	David Miller <davem@...emloft.net>
To:	eric.dumazet@...il.com
Cc:	netdev@...r.kernel.org
Subject: Re: small RPS cache for fragments?

From: Eric Dumazet <eric.dumazet@...il.com>
Date: Tue, 17 May 2011 22:14:48 +0200

> OK but do we have workloads actually needing this optimization at all ?

Yes, I've seen performance graphs where RPS/RFS falls off the cliff
when datagram sizes go from 1024 to 2048 bytes.

Wrt. defrag queue overhead, it still is minor compared to the cost of
processing 1/2 of all packets on one cpu on a 24 core system.

BTW, if we can steer reliably, we could make per-cpu defrag queue if
you worry about it so much :-)
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html