ONTAP Discussions

NDMP and TSM to backup N6040

PASCAL_PETIT
2,741 Views

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

3 REPLIES 3

PASCAL_PETIT
2,741 Views

No ideas?

radek_kubka
2,741 Views

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

PASCAL_PETIT
2,741 Views

Hello radek,

Find hereunder some screeshots from TPC, there was no other disk activities except TSM backup with NDMP.

There is no sequential IO during backup (backend is 6 SATA disk ranks on DS8700).

Some ideas?

,

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