For cron job RelStorage backups (databse not including blobs backed-up seperately, using a PostgreSQL 9.0.x backend), I use both zodbconvert to save FileStorage copies of my database, and pgdump for low-level binary dumps (pg_restore custom format, preserving postgres OIDs). bzip2-compressed, the pgdump backups are always ~2.5 times the size versus the compressed FileStorage -- this puzzles me.
I'm using something in my bash backup script that looks like: $PGDUMP -Fc -o -h $SOCKET_HOST -p $SOCKET_PORT $dbname | bzip2 -c - > $DESTDIR/pgdump-$dbname-$DATESTAMP.bz2 One database that backs up to 45MB bz2-compressed FileStorage file equates to a 123MB bz2-compressed pgdump custom-format file. I would expect such a ratio in running size, but not in compressed backups of similar data. Generally, I'm wondering, for the same data, what it is that makes my high-level FileStorage dump so much smaller in comparison to the lower-level pgdump alternative? Anyone with hunches or PostgreSQL kung-fu to add insight? Side-note: the zodbconvert script seems a perfectly viable mechanism for ZODB backup (regardless of whether one uses a RelStorage backend), but I am not sure if anyone else does this. Sean _______________________________________________ For more information about ZODB, see http://zodb.org/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
