Linux restore optimization

[sherrma]

I recently did some test on Suse (SLES11) linux restore and am very disapointed with the performance result.
I use Lanfree for backup/restore to Jaguar E08 on JD cartridge and Hitachi Protection Platform (HPP) VTL with very good backup performance for the backup of a 103GB file containing dense data:

Network data transfer rate (KB/s) Aggregate data transfer rate (KB/s)
VTL 373'672 321'136
E08(JD) 340'761 327'553
E08 is affected negatively by the mount time during the short 5 minute run of course

But during restore still using lanfree I cannot see better than
Network data transfer rate (KB/s) Aggregate data transfer rate (KB/s)
VTL 108'148 79'049
E08(JD) 173056 89'910

I've tried to modify cache tunning on Linux, txnbytelimit from standard to 10GB, commethod from tcpip to sharedmem but to no end.
Also tried to move to different disk type to a higher end storage type with no result.

have anyone worked on linux restore perfromance for big file and can provide clue on what kind of fine tunning can be done to not see 70% drop in restroe performance.

My AIx machine always loss about 10 to 20% perf during restore even without fine tunning so very surprise by those result.

 

[marclant]

Did your restore go through LanFree? You should be able to tell by the stats:

Total number of bytes transferred:         8.49 GB
LanFree data bytes:                        5.23 MB

Other than that, sounds you were looking at the right tuning options:
http://www-01.ibm.com/support/knowledgecenter/SSGSG7_7.1.0/com.ibm.itsm.perf.doc/c_perf_lanfree.html

 

[sherrma]

Yes Lanfree was working perfectly in there :
Total number of objects restored: 1
Total number of objects failed: 0
Total number of bytes transferred: 103.29 GB
LanFree data bytes: 103.28 GB
Data transfer time: 1,073.76 sec
Network data transfer rate: 100,873.47 KB/sec
Aggregate data transfer rate: 77,795.00 KB/sec
Elapsed processing time: 00:23:13
I think it has something to do with ^Linux parameter but can't find anything in tunning guide or Linux itself.

 

[hogmaster]

Start by verifying how fast you can create a large files on the linux system
use mkfile to create a large (empty file) and use dd to write data to the file.
this test will show if you have a problem with allocation space (mkfile) or writing the data (dd)
The performance depends on your filesystem and your disksystem. But check the filsystem before you look at the disk system.