On Tue, November 15, 2011 17:05, Anatoly wrote: > Good day, > > The speed of send/recv is around 30-60 MBytes/s for initial send and > 17-25 MBytes/s for incremental. I have seen lots of setups with 1 disk > to 100+ disks in pool. But the speed doesn't vary in any degree. As I > understand 'zfs send' is a limiting factor. I did tests by sending to > /dev/null. It worked out too slow and absolutely not scalable. > None of cpu/memory/disk activity were in peak load, so there is of room > for improvement.
What you're probably seeing with incremental sends is that the disks being read are hitting their IOPS limits. Zfs send does random reads all over the place -- every block that's changed since the last incremental send is read, in TXG order. So that's essentially random reads all of the disk. -- David Dyer-Bennet, d...@dd-b.net; http://dd-b.net/ Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/ Photos: http://dd-b.net/photography/gallery/ Dragaera: http://dragaera.info _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
