From mboxrd@z Thu Jan  1 00:00:00 1970
MIME-Version: 1.0
Date: Fri,  3 Sep 2010 22:14:35 -0700
Message-ID: <AANLkTikCR73ntargNqsF9eMXOLXN5+vLS-rG=Qq0+bx4@mail.gmail.com>
From: ron minnich <rminnich@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
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Subject: [9fans] too many system calls.
Topicbox-Message-UUID: 4ef901fa-ead6-11e9-9d60-3106f5b1d025

Glibc /bin/date on Linux runs around 140 system calls. A quick pass
with ratrace shows that plan 9 /bin/date has 10.

The conclusion is clear: plan 9 date has way too much overhead. It's
1/14 the number of system calls of Glibc; why's it so big?

A quick pass on getpid() fixes the problem:

#include	<u.h>
#include	<libc.h>
#include	<tos.h>

int
getpid(void)
{
	return _tos->pid;
}

Now we're down to seven system calls. 1/20 of glibc. Much better! :-)

ron