Hi, On Fri, Oct 26, 2007 at 05:53:33AM -0700, Jason Fesler wrote: > I wonder if it is the defaults for readahead. "man blockdev" and search > for readahead. You might read what your defaults were on the old kernel; > and temporarilly apply them to your drives under the new kernel, and see > what happens with 1.2.10.
yeah I was planning on doing that, however now my production system is up and running again so... ;) Here are the values before (RRDs on sda): # /sbin/blockdev --getra /dev/sda 120 and after (RRDs on md10 raid1+0): # /sbin/blockdev --getra /dev/sd[b-e] /dev/md[01] /dev/md10 256 256 256 256 256 256 512 (siectorsiwe is 512 in both cases) So I went from 120 to 512. Does that mean 4.266 times more data was being read off the drive? This doesn't account for the difference though, as I went from average read of 730KB/s to 36.2MB/s (sorry my previous values were wrong I mistook Avg for Max), which is a factor of more than 50(!). So unless the response is non-linear, I guess I have to look elsewhere... I still suspect a 64bit issue, what do you think? Now that I use rrdtool 1.2.99999[...] the read value dropped even further: 84KB/s, which is consistent with the announcement by the author (10x more updates per second). _______________________________________________ rrd-users mailing list [email protected] https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users
