netdev - Re: Big performance loss from 3.4.63 to 3.10.13 when routing ipv4

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 for Android: free password hash cracker in your pocket

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

Message-ID: <1382529601.7572.2.camel@edumazet-glaptop.roam.corp.google.com>
Date:	Wed, 23 Oct 2013 05:00:01 -0700
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Wolfgang Walter <linux@...m.de>
Cc:	Steffen Klassert <steffen.klassert@...unet.com>,
	David Miller <davem@...emloft.net>, hannes@...essinduktion.org,
	netdev@...r.kernel.org, klassert@...hematik.tu-chemnitz.de
Subject: Re: Big performance loss from 3.4.63 to 3.10.13 when routing ipv4

On Wed, 2013-10-23 at 13:33 +0200, Wolfgang Walter wrote:

> I don't know what this value actually means. But on 3.4.x it is much higher. 
> On a machine with 512MB ram it is 32768, on a machine with 1GB ram it is 
> 262144 and with 16GB ram it is 4194304.
> 

Such huge values should not be needed. We should have at most one dst
per packet in flight.

On a loaded router, a NIC not using BQL could queue around 16,000
packets.

Of course, Qdisc layers could also store a lot of packets, but using the
default pfifo_fast is only adding 1000 packets per interface.

I guess using 65536 as the default value should be safe and reasonable

Have you tried using 32768 or 65536 ?



--
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