Re: Additional LWLOCK_STATS statistics - Mailing list pgsql-hackers

From Andres Freund
Subject Re: Additional LWLOCK_STATS statistics
Date
Msg-id 20150916162627.GF2086@alap3.anarazel.de
Whole thread Raw
In response to Re: Additional LWLOCK_STATS statistics  (Jesper Pedersen <jesper.pedersen@redhat.com>)
Responses Re: Additional LWLOCK_STATS statistics  (Jesper Pedersen <jesper.pedersen@redhat.com>)
List pgsql-hackers
Hi,

On 2015-09-16 10:37:43 -0400, Jesper Pedersen wrote:
>   #ifdef LWLOCK_STATS
>       lwstats->spin_delay_count += SpinLockAcquire(&lock->mutex);
> + 
> +     /*
> +      * We scan the list of waiters from the back in order to find
> +      * out how many of the same lock type are waiting for a lock.
> +      * Similar types have the potential to be groupped together.
> +      *

Except for LW_WAIT_UNTIL_FREE there shouldn't be much in terms of
grouping? Can't you instead iterate and count
counter[waiter->lwWaitMode]++ or so?

Greetings,

Andres Freund



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