netdev - Re: [PATCH net-next] net_sched: sfq: extend limits

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] [day] [month] [year] [list]

Message-Id: <20120105.140843.1291740601133961995.davem@davemloft.net>
Date:	Thu, 05 Jan 2012 14:08:43 -0500 (EST)
From:	David Miller <davem@...emloft.net>
To:	eric.dumazet@...il.com
Cc:	netdev@...r.kernel.org, dave.taht@...il.com
Subject: Re: [PATCH net-next] net_sched: sfq: extend limits

From: Eric Dumazet <eric.dumazet@...il.com>
Date: Thu, 05 Jan 2012 01:18:38 +0100

> SFQ as implemented in Linux is very limited, with at most 127 flows
> and limit of 127 packets. [ So if 127 flows are active, we have one
> packet per flow ]
> 
> This patch brings to SFQ following features to cope with modern needs.
> 
> - Ability to specify a smaller per flow limit of inflight packets.
>     (default value being at 127 packets)
> 
> - Ability to have up to 65408 active flows (instead of 127)
> 
> - Ability to have head drops instead of tail drops
>   (to drop old packets from a flow)
> 
> Example of use : No more than 20 packets per flow, max 8000 flows, max
> 20000 packets in SFQ qdisc, hash table of 65536 slots.
> 
> tc qdisc add ... sfq \
>         flows 8000 \
>         depth 20 \
>         headdrop \
>         limit 20000 \
> 	divisor 65536
> 
> Ram usage : 
> 
> 2 bytes per hash table entry (instead of previous 1 byte/entry)
> 32 bytes per flow on 64bit arches, instead of 384 for QFQ, so much
> better cache hit ratio.
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@...il.com>

Applied.
--
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