On 06/04/2010 06:15 PM, Bob Friesenhahn wrote: > On Fri, 4 Jun 2010, Sandon Van Ness wrote: >> >> Interesting enough when I went to copy the data back I got even worse >> download speeds than I did write speeds! It looks like i need some sort >> of read-ahead as unlike the writes it doesn't appear to be CPU bound as >> using mbuffer/tar gives me full gigabit speeds. You can see in my graph >> here: >> >> http://uverse.houkouonchi.jp/stats/netusage/1.1.1.3_2.html > > I am still not sure what you are doing, however, it should not > surprise that gigabit ethernet is limited to one gigabit of traffic > (1000 Mb/s) in either direction. Theoretically you should be able to > get a gigabit of traffic in both directions at once, but this depends > on the quality of your ethernet switch, ethernet adaptor card, device > driver, and capabilities of where the data is read and written to. > > Bob
The problem is that just using rsync I am not getting gigabit. For me gigabit maxes out at around 930-940 megabits. When I use rsync alone I only was getting around 720 megabits incomming. This is only when its reading from the block device. When reading from the memory (IE: cat a few big files on the server to have them cached) it gets ~935 megabits. The machine is easily able to sustain that read speed (and write) but the problem is getting it to actually do it. The only way I was able to get full gig (935 megabits) was using tar and mbuffer due to it acting as a read-ahead buffer. is there anyway to turn the prefetch up as there really is no reason I should only be getting 720 megabits when copying files off with rsync (or NFS) like I am seeing. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
