MySQL Packet Too Large

[Allen, Benjamin S.]

When the MySQL server's max_allowed_packet setting is set to the max value, 1073741824, DBD::mysql's connection to the database will fail when uploading a VNFS, when the size of the VNFS reaches near 1GB, with "MySQL Packet Too Large". I suspect we should probably set some much smaller ceiling value in chunk_size() in common/lib/Warewulf/DataStore/SQL/MySQL.pm to avoid this problem, as well as avoid large 1GB chunks in the database. The latter I suspect causes some pretty out of control use of caching in the database if configured for a lot of cache (i.e. large innodb_buffer_pool_size).

In my testing hardcoding chunk_size() to return 16MB doesn't change performance from current.

Thoughts on this?

Ben