Date: Thu, 30 Oct 2008 14:05:57 +0000 (UTC) From: Ivan Voras <ivoras@FreeBSD.org> To: cvs-src-old@freebsd.org Subject: cvs commit: src/bin/cat cat.c src/bin/cp utils.c Message-ID: <200810301406.m9UE61VQ043604@repoman.freebsd.org>
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ivoras 2008-10-30 14:05:57 UTC
FreeBSD src repository
Modified files:
bin/cat cat.c
bin/cp utils.c
Log:
SVN rev 184471 on 2008-10-30 14:05:57Z by ivoras
Teach cat(1) and cp(1) to use a larger buffer if enough memory is present
in the system. A simple heuristics is used to detect what is "enough"
memory: if number of physmem pages is greater than 32k (equalling 128 MB
on machines with 4 kB pages).
Typical immediate result of these changes is reduction in context switches
and the goal is to increase efficiency by using large buffers:
before: /usr/bin/time -hlp cat file1 > file2
...
163 voluntary context switches
11194 involuntary context switches
after: /usr/bin/time -hlp ./cat file1 > file2
...
417 voluntary context switches
272 involuntary context switches
Reviewed by: hackers@ (no objections to earlier version of cat patch)
Approved by: gnn (mentor)
MFC after: 4 months
Revision Changes Path
1.33 +21 -2 src/bin/cat/cat.c
1.57 +29 -2 src/bin/cp/utils.c
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