XtraBackup data.qp increase in size


We have a Percona 5.5 instance which is being backed up by XtraBackup. We are running an archiving operation on this database, so the ibdata1 table space never grows, although new data is being stored into it. We archive / prune quicker then we store new data.

However the compressed backup result still increases in size. I’m trying to understand how this is possible, since the tablespace is not increasing.


Any feedback on the matter ?

If you have innodb_file_per_table enabled, the size of ibdata1 may not be increasing, but the size of the individual table data files (i.e. mytable.ibd) are likely increasing in size.

Hi Scott,

Thanks for your comment, however we are not using innodb_file_per table enabled… Also i can confirm that the entire size of the data directory has not increased in months, however the end result backup has increased consistently each day

Interesting. Only other thing I can think of is perhaps your system is getting busier, so the transaction log that is recorded during the backup (for preparing it later) may be growing larger?

One way to check would be to simply pull an older backup and compare it to the new backup with a quick visual inspection of the folder contents. If the size difference is large enough, you may be able to spot it that way.