On Friday, July 06, 2012 01:38:56 PM Daniel Farina wrote: > ll, I don't know a > mechanism besides slow file system truncation time that would explain > why DELETE would be significantly faster. There is no filesystem truncation happening. The heap and the indexes get mapped into a new file. Otherwise rollback would be pretty hard to implement.
I guess the biggest cost in a bigger cluster is the dropping the buffers that were formerly mapped to that relation (DropRelFileNodeBuffers). Andres -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
