Re: Why is my DSL for friggin' slow on Linux 9.1?

From: Arthur Hagen (art_at_broomstick.com)
Date: 02/28/05 

Date: Mon, 28 Feb 2005 09:35:50 -0500

mjt <mjtobler@removethis_mail.ru> wrote:
>
> here's my tweaks, which gives good performance...
>
> echo 8388608 > /proc/sys/net/core/rmem_max
> echo 8388608 > /proc/sys/net/core/wmem_max
> echo 131072 > /proc/sys/net/core/rmem_default
> echo 131072 > /proc/sys/net/core/wmem_default
> echo "4096 87380 8388608" > /proc/sys/net/ipv4/tcp_rmem
> echo "4096 65536 8388608" > /proc/sys/net/ipv4/tcp_wmem
> echo "8388608 8388608 8388608" > /proc/sys/net/ipv4/tcp_mem
> echo 2500 > /proc/sys/net/core/netdev_max_backlog
>
> echo 0 > /proc/sys/net/ipv4/tcp_ecn
> echo 0 > /proc/sys/net/ipv4/ip_no_pmtu_disc
> echo 1 > /proc/sys/net/ipv4/tcp_sack
> echo 1 > /proc/sys/net/ipv4/tcp_window_scaling
> echo 1 > /proc/sys/net/ipv4/tcp_timestamps
> echo 128 > /proc/sys/net/ipv4/ip_default_ttl

First of all, why do you specify "tweaks" that are default? That's a waste
(and shows a lack of understanding, much like adding umpteen parameters to
CFLAGS, even though most of them are already implied).

As for the specific tweaks above, some of them will reduce throughput and/or
increase memory use, and I strongly suggest that no-one adds any of the
above to their system without first understanding *exactly* what the tweak
does; knowing *why* it would make sense to do so on their system, compared
to the default values. 

-- 
*Art

Relevant Pages