--use-memory= - No backup speed increase?

[pamamolf]

Hi

I was try to run a backup of my database only using:

innobackupex --no-timestamp --databases="databasename" /backup/mysql

and if i am not wrong that uses the default ram 100mb value and it takes to finish the backup 18 minutes.

Then i run it using:

innobackupex --no-timestamp --use-memory=8G --databases="databasename" backup/mysql

and it takes exactly the same time 18 minutes.

Why i don’t get any speed increase of backup?

Thanks

[scott.nemes]

Hi pamamolf;

The --use-memory option is only valid during the apply-log step, so that will not help speed up the backup itself

If you have InnoDB file per table enabled, look at the --parallel option which may help speed up the backup. Note if you are not using file per table that option will not help since all of your table data will be in the one ibdata1 file.

The limiting factor for backup speed tends to be your disk speed. So the best way to speed up your backup is to have it write to a separate disk or physical partition so that the backup is not competing with your database (and other processes) for drive access.

http://www.percona.com/doc/percona-xtrabackup/2.2/innobackupex/innobackupex_option_reference.html#cmdoption-innobackupex–parallel

-Scott

[pamamolf]

Thanks scott.nemes