Re: Checkpointer on hot standby runs without looking checkpoint_segments

On 8 June 2012 14:47, Robert Haas <robertmhaas@gmail.com> wrote:

>> ISTM that we should avoid triggering a checkpoint on the master if
>> checkpoint_segments is less than wal_keep_segments. Such checkpoints
>> serve no purpose because we don't actually limit and recycle the WAL
>> files and all it does is slow people down.
>
> On the other hand, I emphatically disagree with this, for the same
> reasons as on the other thread.  Getting data down to disk provides a
> greater measure of safety than having it in memory.  Making
> checkpoint_segments not force a checkpoint is no better than making
> checkpoint_timeout not force a checkpoint.

Not sure which bit you are disagreeing with. I have no suggested
change to checkpoint_timeout.

What I'm saying is that forcing a checkpoint to save space, when we
aren't going to save space, makes no sense.

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