Re: Fix checkpoint skip logic on idle systems by tracking LSN progress

On 11/10/16 10:28 AM, Stephen Frost wrote:

>> diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
> [...]
>> +			if (log_checkpoints)
>> +				ereport(LOG, (errmsg("checkpoint skipped")));
> 
> Do we really need to log that we're skipping a checkpoint..?  As the
> point of this is to avoid write activity on a system which is idle, it
> doesn't make sense to me to add a new cause for writes to happen when
> we're idle.

log_checkpoints is not enabled by default, though, so if the user does
enable it don't you think they would want to know when checkpoints
*don't* happen?

Or are you thinking the main use of this logging is to determine when
checkpoints are too close together and so skipped checkpoints aren't
very important?

Thanks,
-- 
-David
david@pgmasters.net