From: David Wuertele <dave-gnus@bfnet.com>
To: linux-kernel@vger.kernel.org
Subject: Do I need kswapd if I don't have swap?
Date: Sat, 22 Nov 2003 17:35:57 -0800 [thread overview]
Message-ID: <m3d6bj3lz6.fsf@bfnet.com> (raw)
Using 2.4.18 on my 32MB RAM embedded MIPS system, malloc() goes
bye-bye:
/* Malloc as much as possible, then return */
#include <stdio.h>
#define UNIT 1024 /* one kilobyte */
int main ()
{
unsigned int j, totalmalloc=0, totalwrote=0, totalread=0;
while (1) {
unsigned char *buf = (unsigned char *) malloc (UNIT);
if (!buf) return 0;
totalmalloc += UNIT; fprintf (stderr, "%u ", totalmalloc);
for (j=0; j<UNIT; j++) buf[j] = j % 256;
totalwrote += UNIT; fprintf (stderr, "%u ", totalwrote);
for (j=0; j<UNIT; j++) if (buf[j] != (j % 256)) return -1;
totalread += UNIT; fprintf (stderr, "%u\n", totalread);
}
}
I expected this program to malloc most of my embedded MIPS's 32MB of
system RAM, then eventually return with a -1 or a -2. Unfortunately,
it hangs having finally printed:
M26916864
W26916864
R26916864
The malloc call isn't even returning. What could explain that?
I don't have swap space configured, and I notice several kernel
threads that I figure might be assuming I have swap. For example:
3 root S [ksoftirqd_CPU0]
4 root S [kswapd]
5 root S [bdflush]
6 root S [kupdated]
7 root S [mtdblockd]
Do I need any of these if I don't have swap? Are there any special
kernel configs I should be doing if I don't have swap?
Thanks,
Dave
next reply other threads:[~2003-11-23 1:40 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-11-23 1:35 David Wuertele [this message]
2003-11-23 2:10 ` Do I need kswapd if I don't have swap? Måns Rullgård
2003-11-23 3:22 ` Valdis.Kletnieks
[not found] <URy0.Sx.3@gated-at.bofh.it>
2003-11-24 7:37 ` Ihar 'Philips' Filipau
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