But each dd will only see the bandwidth from a single server. So 6 dd's run simultaneously will in aggregate see more than 20MB/s - but no single one will James Burnash, Unix Engineering -----Original Message----- From: Mohit Anchlia [mailto:mohitanchlia at gmail.com] Sent: Wednesday, April 20, 2011 3:05 PM To: Burnash, James; landman at scalableinformatics.com Cc: gluster-users at gluster.org Subject: Re: Performance Like I mentioned several times my tests are running concurrent threads and doing concurrent writes. So overall throughput per sec should be atleast 20 X 3 = 60 MB/s. On Wed, Apr 20, 2011 at 12:01 PM, Burnash, James <jburnash at knight.com> wrote: > Gluster doesn't "spread the load across 6 servers", because the file is only being retrieved from one server (as Joe has stated). So you are limited to the throughput of that server. Even with the files replicated, only one copy is ever read at a time from a single client. > > Hopefully that makes it clearer. > > Nice work Joe - very helpful to the rest of us, I think. > > James Burnash, Unix Engineering > > -----Original Message----- > From: gluster-users-bounces at gluster.org [mailto:gluster-users-bounces at gluster.org] On Behalf Of Mohit Anchlia > Sent: Wednesday, April 20, 2011 2:59 PM > To: landman at scalableinformatics.com; gluster-users at gluster.org > Subject: Re: Performance > > Correct. I was referring to gluster performance test that I am running > using gluster client that spreads the load accross all the servers. > From that test I get only 20MB/s not 60MB/s. > > Also, at this point what would be your recommendation? > > On Wed, Apr 20, 2011 at 11:56 AM, Joe Landman > <landman at scalableinformatics.com> wrote: >> On 04/20/2011 02:54 PM, Mohit Anchlia wrote: >>> >>> Thanks again! But what I don't understand is that I have 3 X 2 servers >>> so I would expect 20 X 3 = 60 MBPS total atleast. My load is getting >>> spread accross 3 X 2 servers in distributed replica. If I was using >>> just one gluster server I would understand but with 6 it makes no >>> sense.. >> >> The dd is going to only one server, unless you are doing 6 simultaneous >> dd-s. >> >> >> -- >> Joseph Landman, Ph.D >> Founder and CEO >> Scalable Informatics Inc. >> email: landman at scalableinformatics.com >> web ?: http://scalableinformatics.com >> ? ? ? http://scalableinformatics.com/sicluster >> phone: +1 734 786 8423 x121 >> fax ?: +1 866 888 3112 >> cell : +1 734 612 4615 >> > _______________________________________________ > Gluster-users mailing list > Gluster-users at gluster.org > http://gluster.org/cgi-bin/mailman/listinfo/gluster-users > > > DISCLAIMER: > This e-mail, and any attachments thereto, is intended only for use by the addressee(s) named herein and may contain legally privileged and/or confidential information. If you are not the intended recipient of this e-mail, you are hereby notified that any dissemination, distribution or copying of this e-mail, and any attachments thereto, is strictly prohibited. If you have received this in error, please immediately notify me and permanently delete the original and any copy of any e-mail and any printout thereof. E-mail transmission cannot be guaranteed to be secure or error-free. The sender therefore does not accept liability for any errors or omissions in the contents of this message which arise as a result of e-mail transmission. > NOTICE REGARDING PRIVACY AND CONFIDENTIALITY Knight Capital Group may, at its discretion, monitor and review the content of all e-mail communications. http://www.knight.com >
