Monitoring log segment usage

[Former Member]

We are trying to monitor our redo log usage rate. Using the m_log_segments_reset we can see what the currently used segment is but since the segment_id is static and the log segments cycles by default we cannot tell how many logs have been used for a period of time.

In Oracle you can query v$log and the sequence# increments each time a log starts to be used. Is there an equivalent in Hana?

[lbreddemann · Accepted solution]

Hi Jason,

why don't you just check for how many log backups have been written?

You get one backup for each "finished" log segment, so for your requirement that should work just fine.

- Lars

[Former Member · Accepted solution]

Thank you for the response Lars. Are the log backups tracked in a Hana system table? Most of our operations monitoring is done by separate monitoring servers so I was hoping that there was an easy way to get this information by running a query rather than needing access to the backup log directory or running a script on the database.

[lbreddemann · Accepted solution]

Hi Jason,

you could use the information from m_backup_catalog (SAP HANA Reference: M_BACKUP_CATALOG). Just filter for the backup type and you have your "log creation rate" ;-).

- Lars

[Former Member · Accepted solution]

Thanks again Lars! I did not think to look at m_backup_catalog and m_backup_catalog_files. I thought these were only tracking data backups.