archive_blob varies from 5 to 300MB



I’ve got constantly problems with the size of the piwik database. It got better with the automated purge of archived logs but I’m worried about the table sof the archivde data, too.

If I look at the database usage I can see that the size of the monthly size of the archive_blob tables vary from 5.1Mb to 297.3 Mb. That very much, espacially considering that the number of visitors is relatively constant.

Archiving is triggered by the browser and seems to work without (visible) errors. Nevertheless I guess sometimes the process dies leaving unprocessed data in the table.

Is there something I can check for errors or process the data afterwards for old archive_blob tables?
If this is considered normal behaviour is there data I can purge to safe table space without losing the historical data? I’m only interested in general data comparison, I don’t need to be able to reproduce every single visit or hit which happend months ago.