On Wed, 2004-11-17 at 21:28 +0100, Arjan van de Ven wrote:
another interesting test might be the following:
disable readahead (both services), store the attached file as /tmp/files
and put the following near the top of /etc/rc.sysinit:
/usr/sbin/readahead `/bin/cat /tmp/files`
I had to move it a bit further down so it gets picked up by top (which
in turn requires /proc):
--- /etc/rc.sysinit.orig
+++ /etc/rc.sysinit
@@ -26,8 +26,13 @@
mount -n -t proc /proc /proc
[ -d /proc/bus/usb ] && mount -n -t usbfs /proc/bus/usb /proc/bus/usb
mount -n -t sysfs /sys /sys >/dev/null 2>&1
+# Log top output for boot analysis
+/usr/local/sbin/bootop start
+
+/usr/sbin/readahead `/bin/cat /tmp/files`
+
. /etc/init.d/functions
# Check SELinux status
selinuxfs=`awk '/ selinuxfs / { print $2 }' /proc/mounts`
The result:
http://www.klika.si/ziga/bootchart/bootchart-diskless.png
There's a 20 MB load of files in your readahead list and they are being
read for 15 seconds. I guess a 26.60 MB/sec 'hdparm -t' suggests room
for improvement? Note that this is on a 4200 RPM drive.
--
Ziga