Re: pgbench -i spends all its time doing CHECKPOINT

Tatsuo Ishii wrote:
> > Could we remove lines 552-560 of pgbench.c? The behavior that guarded
> > against is long gone, and forcing a checkpoint every few thousand tuples
> > seems to be putting a huge crimp in the speed of pgbench -i ...
>
> Yup. Maybe we could ifdef'ed out until we implement true UNDO...

I think we should just remove it. The idea that we are going to do UNDO
which allows unlimited log file growth for long transactions seems like
a loser to me.

Actually, that brings up a question I had. In 7.1.0, we didn't recycle
WAL segements that were used by open transactions during CHECKPOINT,
while in 7.1.3 and later, we do recycle them after CHECKPOINT. My
question is if we do a big transaction that needs 10 log segments, do we
force an early CHECKPOINT to clear out the WAL segments or do we just
wait for the proper interval?

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