Re: Cpu usage 100% on slave. s_lock problem. - Mailing list pgsql-performance

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/
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