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From: Eric Wong <normalperson@yhbt.net>
Newsgroups: gmane.comp.lang.ruby.kgio.general
Subject: Re: [PATCH 3/3] add `#kgio_writev` and `#kgio_trywritev`
Date: Thu, 31 May 2012 14:56:02 -0700
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Eric Wong <normalperson@yhbt.net> wrote:
> True about kgio for mainly for sockets, but 1M might be too small for
> long fat networks (high latency, high bandwidth).
> 
> /proc/sys/net/ipv4/tcp_wmem on my stock Linux 3.4 system says the
> write buffer can grow up to 4M.

I've checked some setups I use (75-120ms over 1 gigabit) and those have
the max tcp_wmem set to 16M(!).  I've also known (and pity) folks that
have to deal with ~500ms latency on their LFNs.