expand_number() for fetch'es -B and -S switches

Dag-Erling Smørgrav des at des.no
Thu Sep 2 12:55:21 UTC 2010


Alexander Best <arundel at 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
-- 
Dag-Erling Smørgrav - des at des.no


More information about the freebsd-hackers mailing list