Re: Cpu usage 100% on slave. s_lock problem.

On 2013-08-27 09:57:38 -0500, Merlin Moncure wrote:
> + bool
> + RecoveryMightBeInProgress(void)
> + {
> + /*
> + * We check shared state each time only until we leave recovery mode. We
> + * can't re-enter recovery, so there's no need to keep checking after the
> + * shared variable has once been seen false.
> + */
> + if (!LocalRecoveryInProgress)
> + return false;
> + else
> + {
> + /* use volatile pointer to prevent code rearrangement */
> + volatile XLogCtlData *xlogctl = XLogCtl;
> +
> + /* Intentionally query xlogctl without spinlocking! */
> + LocalRecoveryInProgress = xlogctl->SharedRecoveryInProgress;
> +
> + return LocalRecoveryInProgress;
> + }
> + }

I don't think it's acceptable to *set* LocalRecoveryInProgress
here. That should only be done in the normal routine.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services