On 12/8/2011 11:50 PM, Dallin Jones wrote: > I am having a horrible time getting my servers to actually perform at > the marketing that 3ware says I should be getting. I have used dd to > copy from /dev/zero to and image file and I am only getting around > 40-50 megs/sec. I figure that I should be getting better than that, > but I'm not quite sure if my bench mark is even the right thing. > > Currently things aren't too bad, but I am trying to setup glusterfs in > a replicated/distributed setup (10 w/3 drives each). Unfortunately > when I run dd against my gluster volume, I only get 3MBs. This is > crazy slow to the point of completely unusable. I know the gluster > team recommend using GB Ethernet, but I figure that I should at least > be able to max out my current 100 Mb network pretty fast. I'm not even > coming close though. > > So the question: I remember so coworkers previously say there were > issues with 3ware raid cards, but that he was able to fix the problem. > I wonder if I am hitting the same bug, or I'd maybe it is something > else. > > I have turned on the write cache as well as blockdev --setra 16384, > but it doesn't appear to help much. I did however try to enable the > write cache and got a little speed increase, but nothing like I > expected. > > Any thoughts on better ways to benchmark this, and also thoughts on > tuning my 3ware controller? I am using a 32 but version of Linux, > Hopefully that is enough info to point me in the right direction. > > > --Dallin Jones > > /* > PLUG: http://plug.org, #utah on irc.freenode.net > Unsubscribe: http://plug.org/mailman/options/plug > Don't fear the penguin. > */ > > > ----- > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2012.0.1873 / Virus Database: 2101/4668 - Release Date: 12/08/11 > > Some things you might want to look at is full duplex vs half duplex connections and are these direct links vs routed links? Also make sure your cables proximity to electromagnetic sources such as power boxes and cables is limited. Even with fully shielded cables there is still some signal bleed that can get in the way with large cable clusters too but that should be nearly negligible in this case.
Jason /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
