Re: BUG #3674: Unnecessary checkpoints by WAL Writer

"ITAGAKI Takahiro" <itagaki.takahiro@gmail.com> writes:
> WAL Writer requests unnecessary checkpoints with CHECKPOINT_CAUSE_XLOG.
> RedoRecPtr, declared in xlog.c, is initialized at StartupXLOG() but never
> updated in WAL Writer because it never calls XLogInsert(). It judges excess
> of segments wrongly.

Good catch.  I think the best fix for this is to make XLogWrite call
GetRedoRecPtr and recheck the condition before actually sending a
signal.

            regards, tom lane