> I want my VMs to run fast - so is it deduplication that really slows > things down? > > Are you saying raidz2 would overwhelm current I/O controllers to where > I could not saturate 1 GB network link? > > Is the CPU I am looking at not capable of doing dedup and compression? > Or are no CPUs capable of doing that currently? If I only enable it > for the backup filesystem will all my filesystems suffer performance > wise? > > Where are the bottlenecks in a raidz2 system that I will only access > over a single gigabit link? Are the insurmountable?
I'm not sure if anybody can answer your questions. I will suggest you just try things out, and see for yourself. Everybody would have different techniques to tweak performance... If you want to use fast compression and dedup, lots of cpu and ram. (You said 4G, but I don't think that's a lot. I never buy a laptop with less than 4G nowadays. I think a lot of ram is 16G and higher.) As for raidz2, and Ethernet ... I don't know. If you've got 5 disks in a raidz2 configuration ... Assuming each disk can sustain 500Mbits, then theoretically these disks might be able to achieve 1.5Gbit or 2.5Gbit with perfect efficiency ... So maybe they can max out your Ethernet. I don't know. But I do know, if you had a stripe of 3 mirrors, they would have absolutely no trouble maxing out the Ethernet. Even a single mirror could just barely do that. For 2 or more mirrors, it's cake. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
