hi, all: When I was testing glusterfs performance by iozone with only ONE machine, I got the following chart: https://dl.dropbox.com/u/33453649/perf_htm_m19da4047.jpg Y axis represent disk throughput in kb/s. X axis represent test cases. It is obvious that R+W case has the worst read performance, R+W means you turn on both Read-ahead xlator and Write-behind xlator. Unfortunately, that`s the default configuration of glusterfs. Though I run glusterfs only on one machine, I think this result explains something. Maybe you have more insight on it. More info: ------------------------- cmdline: ./iozone -a -n 16g -g 16g -i 0 -i 1 -i 2 -i 3 -f /mnt/iozone -Rb no-rh.xls -y 4096k CPU: intel i3-2120 X 4 RAM: 8G Glusterfs Version: 3.3 Volume info: Volume Name: abc Type: Distribute Volume ID: 6e0104f1-d32a-4ed4-b011-d29ccf27abe1 Status: Started Number of Bricks: 1 Transport-type: tcp Bricks: Brick1: 10.1.82.224:/abc Options Reconfigured: performance.io-cache: off performance.quick-read: off performance.read-ahead: on performance.write-behind: on -------------------------------------------- Best Regards. Jules Wang. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://supercolony.gluster.org/pipermail/gluster-users/attachments/20121214/be35b3d6/attachment.html>
John Mark Walker
2012-Dec-17 15:18 UTC
[Gluster-users] probable cause of read performance issue
Thanks for sending to the list. I'm not sure what the solution is, since most people need R+W. For 3.4, there are some features around the use case of WORM (write once, read many) which might improve performance for the use case you're testing. Could you perform the same test with the qa5 release from last week? -JM ----- Original Message -----> hi, all: > When I was testing glusterfs performance by iozone with only ONE > machine, I got the following chart:> https://dl.dropbox.com/u/33453649/perf_htm_m19da4047.jpg> Y axis represent disk throughput in kb/s. X axis represent test > cases.> It is obvious that R+W case has the worst read performance, R+W means > you turn on both Read-ahead xlator and Write-behind xlator. > Unfortunately, that`s the default configuration of glusterfs.> Though I run glusterfs only on one machine, I think this result > explains something. Maybe you have more insight on it.> More info: > ------------------------- > cmdline: ./iozone -a -n 16g -g 16g -i 0 -i 1 -i 2 -i 3 -f /mnt/iozone > -Rb no-rh.xls -y 4096k > CPU: intel i3-2120 X 4 > RAM: 8G > Glusterfs Version: 3.3 > Volume info: > Volume Name: abc > Type: Distribute > Volume ID: 6e0104f1-d32a-4ed4-b011-d29ccf27abe1 > Status: Started > Number of Bricks: 1 > Transport-type: tcp > Bricks: > Brick1: 10.1.82.224:/abc > Options Reconfigured: > performance.io-cache: off > performance.quick-read: off > performance.read-ahead: on > performance.write-behind: on > --------------------------------------------> Best Regards. > Jules Wang.> _______________________________________________ > Gluster-users mailing list > Gluster-users at gluster.org > http://supercolony.gluster.org/mailman/listinfo/gluster-users-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://supercolony.gluster.org/pipermail/gluster-users/attachments/20121217/7f3ef22b/attachment.html>