Re: CHECKPOINT_WARNING GUC variable addition

Neil Conway wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > The following patch adds a GUC variable CHECKPOINT_WARNING which
> > generates a server log message if the checkpoint caused by WAL file
> > filling happens more frequently than (default) 30 seconds.
>
> +    Checkpoints are fairly expensive because they force all dirty kernel
> +    buffers to disk using the operating system <literal>sync()</> call.
> +    Busy servers may fill checkpoint segment files too quickly,
> +    causing excessive checkpointing. If such forced checkpoints happen
> +    more than <varname>CHECKPOINT_WARNING</varname> seconds
>
> That should be: "happen more [frequently] than ..."

Great.  New text:

+    Checkpoints are fairly expensive because they force all dirty kernel
+    buffers to disk using the operating system <literal>sync()</> call.
+    Busy servers may fill checkpoint segment files too quickly,
+    causing excessive checkpointing. If such forced checkpoints happen
+    more frequently than <varname>CHECKPOINT_WARNING</varname> seconds,
+    a message, will be output to the server logs recommending increasing
+    <varname>CHECKPOINT_SEGMENTS</varname>.

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