NDMP and TSM to backup N6040

PASCAL_PETIT · ‎2012-01-06

Hi falks,

Best wishes for 2012

Does someone know what type of IO is generated (normal or sequential) during backup node type=backupimage (TSM command)?

I checked with TPC and see only normal read IO during backup (I expected sequential IO), so when we performed a full backup we have bad performance due to disk (SATA) and only read cache hit ratio to 40%.

Read cache hit ratio is checked on backend (DS8700), do you know a tool to check on N6040?

Do you know a way to improve backup performance?

FYI we have same performance pb with some big volumes (10T) or little volumes (300G)

Thank you for your help

PASCAL_PETIT · ‎2012-01-09

No ideas?

radek_kubka · ‎2012-01-09

Hi,

I think with full backup there is not many ways to improve the performance, as you are doing a lot of sequential reads, which ONTAP doesn't like too much (I have no idea why TPC is reporting there is no sequential IO - this is wrong in my opinion)

If we are talking about incremental backups, then TSM 6.1 or later is definitely better than earlier versions performance-wise:

“NetApp Snapshot Difference API enables TSM to reduce the time required for progressive incremental file backups by eliminating client filesystem scans.”

http://www.enterprisestrategygroup.com/2009/04/esg-lab-validation-report-ibm-tsm-6-1-unified-data-protection-and-recovery-management/

Regards,

Radek