DS wrote:
> Hello,
>
> I need some help to tunning my storage.
...
> TIME 43 sekund
What kernel? when I test on my 2.6.23.9-85.fc8 and 2.6.22.5 boxes, I
see 2 and 7 seconds for rewrite, respectively.
but granted, on ext3 I get 0 seconds for every run.
Also the difference appears to be O_TRUNC (which the perl script does);
if I code it in c:
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
void main(void)
{
int i;
int fd;
char file[4];
for (i = 0; i < 100; i++) {
sprintf(file, "%d.txt", i);
fd = open(file, O_CREAT|O_RDWR|O_TRUNC, 0644);
write(fd, "aaaaaaaaaaaaaaaaaaa\n");
close(fd);
}
}
rewrite is a bit slower w/ O_TRUNC in place, plenty fast w/o it. Not
sure about the xfs/ext3 difference... this is probably a side-effect of
flushes xfs put into place on truncate (IIRC?)
-Eric
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