No, I haven't isolated the cause to only be uptime related. In my original email I mentioned that "as suggested by someone in the thread, it's probably not directly related to system uptime, but instead related to usage - the more usage, the worse the performance."
I've been starting my system with different combinations of applications running to see what access patterns cause the most slowdown. So far, I don't have enough data to give anything concrete. This weekend I'll try some tests such as the one you describe, and see what happens. I have a strong suspicion that rTorrent is to blame, since I haven't seen major slowdowns in the last few days with rTorrent not running. rTorrent preallocates the space needed for the file download (and I'm downloading large 4GB+ files using it), and then writes to them in an unpredictable pattern, so maybe ZFS doesn't like being touched this way? On Wed, Jan 6, 2010 at 2:21 PM, Ivan Voras <ivo...@freebsd.org> wrote: > On 3.1.2010 17:42, Garrett Moore wrote: > > > I'm having problems with ZFS performance. When my system comes up, > > read/write speeds are excellent (testing with dd if=/dev/zero > > of=/tank/bigfile and dd if=/tank/bigfile of=/dev/null); I get at least > > 100MB/s on both reads and writes, and I'm happy with that. > > > > The longer the system is up, the worse my performance gets. Currently my > > system has been up for 4 days, and read/write performance is down to > about > > 10MB/s at best. > > Are you sure you have isolated the cause to be only the uptime of the > machine? Is there no other change between the runs? E.g. did you stop > all other services and applications on the machine before doing the test > for the second time? Can you create a big file (2x memory size) when the > machine boots, measure the time to read it, then read it again after a > few days when you notice performance problems? > > > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org" > _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
