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
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