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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Alexander Best <arundel@freebsd.org>
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Date: Thu, 02 Sep 2010 14:55:20 +0200
In-Reply-To: <20100902122348.GA38047@freebsd.org> (Alexander Best's message of
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Cc: freebsd-hackers@freebsd.org
Subject: Re: expand_number() for fetch'es -B and -S switches
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Alexander Best <arundel@freebsd.org> writes:
> the current maximum buffer limit of fetch(1) actually is around 1G. i
> think 1M is not enough, because if people are pulling data over fast
> lines they'll have almost constant disk writes. how about 100M then?
> ;)

Large buffer sizes are *not* better, since fetch(1) will alternate
between filling the buffer and writing it to disk.  The buffer should
not be too small, but it should not be too large either; the sweet spot
is somewhere around 128 kB.

> on the other hand why have a maximum limit? if people want to have a
> buffer of 100 gigabyte why shouldn't they? it's their decision
> actually.

Good point...  although if they set it too high, either malloc(3) will
fail - if they're lucky - or fetch(1) will crash when the system runs
out of physical RAM and swap, and they'll have to start over.

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no