On Sat, Dec 12, 2009 at 11:39 AM, Brent Jones <br...@servuhome.net> wrote: > On Sat, Dec 12, 2009 at 7:55 AM, Bob Friesenhahn > <bfrie...@simple.dallas.tx.us> wrote: >> On Sat, 12 Dec 2009, Brent Jones wrote: >> >>> I've noticed some extreme performance penalties simply by using snv_128 >> >> Does the 'zpool scrub' rate seem similar to before? Do you notice any read >> performance problems? What happens if you send to /dev/null rather than via >> ssh? >> >> Bob >> -- >> Bob Friesenhahn >> bfrie...@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ >> GraphicsMagick Maintainer, http://www.GraphicsMagick.org/ >> > > Scrubs on both systems seem to take about the same amoutn of time (16 > hours, on a 48TB pool, with about 20TB used) > > I'll test to dev/null tonight > > -- > Brent Jones > br...@servuhome.net >
I tested send performance to /dev/null, and I sent a 500GB filesystem in just a few minutes. The two servers are linked over GigE fiber (between two cities) Iperf output: [ ID] Interval Transfer Bandwidth [ 5] 0.0-60.0 sec 2.06 GBytes 295 Mbits/sec [ ID] Interval Transfer Bandwidth [ 4] 0.0-60.0 sec 2.38 GBytes 341 Mbits/sec Usually a bit faster, but some other stuff goes over that pipe. Though looking at network traffic between these two hosts during the send, I see a lot of network traffic (about 100-150Mbit usually) during the send. So theres traffic, but a 100MB send has taken over 10 minutes and still not complete. But given 100Mbit/sec, it should take about 10 seconds roughly, not 10 minutes. There is a little bit of disk activity, maybe a MB/sec on average, and about 30 iops. So it seems the hosts are exchanging a lot of data about the snapshot, but not actually replicating any data for a very long time. SSH CPU usage is minimal, just a few percent (arcfour, but tried others, no difference) Odd behavior to be sure, and looks very familiar to what snapshot replication did back in build 101, before they made significant speed improvements to snapshot replication. Wonder if this is a major regression, due to changes in newer ZFS versions, maybe to accomodate de-dupe? Sadly, I can't roll back, since I already upgraded my pool, but I may try upgrading to 129, but my IPS doesn't seem to recognize the newer version yet. -- Brent Jones br...@servuhome.net _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
