cubicweb #2509722 db-dump --portable should allow blocksize configuration [open]

The DatabaseIndependentBackupRestore class hardcodes number of records used by executemany to dump / pickle the records (i.e. 2000 for cw entities). Some records happen to store huge blobs which makes 2000 records too big to fit into memory.

A new command line option could be added to configure blocksize.

done in<not specified>
load left0.500
closed by<not specified>