From: Clifford Heath <cjh_nospam@...>
Date: 2002-06-21T10:48:39+09:00
Subject: Re: Why is I/O slow?

Yukihiro Matsumoto wrote:
> It's due to stdio buffering.

But our tests on Linux with fread and glibc indicate that there is no
extra buffering happening. stdio is *capable* of buffering, but in this
case it isn't *actually* buffering (it's not possible to move A->B->C
as fast as A->C, from my argument about bandwidth). stdio libraries that
still do double copies must surely be rare now...?

>  In the future version, Ruby will do its
> own IO buffering without using stdio, so that it can tweak IO buffer
> freely without portability problem.

With respect, this doesn't sound like a smart idea. The glibc folk have
spent vast effort making it fly, and you want to bypass it?

Anyhow, thanks to Radek for the advice, I've got 1.6.7 and the performance
of sysread seems comparable to read now.

--
Clifford Heath