November 6, 2011


Figure 1: This shows preliminary results from testing from Sunday Nov 6. The summary is that simultaneous iperf is good from all hosts (9.9+ Gbps) . Reading from disk and writing memory is reasonable with performance of 7.5 -8.5 Gbit/s, but I think could do with some improvement. Disk to disk performance is only 5.0 Gbps and not really adequate for the test. We are using 2000 atlas files of around 500MB on each node for the transfers. We had better performance with 10G files written with 'dd'. Graph pulled from cacti for the Brocade.

Now attempting to improve disk performance be removing LVM and and changing the Raid controller to write through. Also note that scdemo00 and scdemo01 had their raid stripe set at 64 kb.

 Delete a logical drive
 [root@scdemo00 ~]# /opt/MegaRAID/MegaCli/MegaCli64 -CfgLdDel -L1 -a0
 Get the enclosure device ID:
 [root@scdemo00 ~]# /opt/MegaRAID/MegaCli/MegaCli64 -EncInfo -aALL
 Create a logical drive 
 [root@scdemo00 ~]# /opt/MegaRAID/MegaCli/MegaCli64  -CfgLdAdd -r0 [32:2,32:3,32:4,32:5,32:6] WT ADRA Direct -strpsz1024 -a0

Dramatic improvement with these new disk settings, but still using large files.

-- IanGable - 2011-11-06

  • cacti_notes_2011-011-06.png:
Edit | Attach | Watch | Print version | History: r14 | r4 < r3 < r2 < r1 | Backlinks | Raw View | More topic actions...
Topic revision: r2 - 2011-11-07 - igable
  • Edit
  • Attach
This site is powered by the TWiki collaboration platform Powered by PerlCopyright © 2008-2020 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding TWiki? Send feedback