On Fri, Jun 01, 2012 at 01:50:55PM -0500, Michael Cronenworth wrote:
Not a single person who has claimed a performance or semantic win for
this /tmp move has replied when asked for proof.
$ time dd if=/dev/zero of=/tmp/file bs=1M count=10240
10240+0 records in
10240+0 records out
10737418240 bytes (11 GB) copied, 4.95536 s, 2.2 GB/s
dd if=/dev/zero of=/tmp/file bs=1M count=10240 0.00s user 3.44s system 69% cpu 4.956 total
No visual shanges in system behavior.
How much memory do you have to be able to write 11GB to /tmp ???
$ time dd if=/dev/zero of=/var/tmp/file bs=1M count=10240
10240+0 records in
10240+0 records out
10737418240 bytes (11 GB) copied, 59.2188 s, 181 MB/s
dd if=/dev/zero of=/var/tmp/file bs=1M count=10240 0.00s user 54.26s system 91% cpu 59.239 total
SSD disk. System becomes unresponsive for a couple of tens of seconds.
$ time dd if=/dev/zero of=$HOME/file bs=1M count=10240
10240+0 records in
10240+0 records out
10737418240 bytes (11 GB) copied, 75.1548 s, 143 MB/s
dd if=/dev/zero of=$HOME/file bs=1M count=10240 0.01s user 71.30s system 94% cpu 1:15.16 total
SATA disk. System becomes less responsive for a couple of seconds.
Does that counts as a proof? ext4 on /var and /home.