Re: Reduce ProcArrayLock contention

On Wed, Aug 5, 2015 at 10:59 AM, Amit Kapila <amit.kapila16@gmail.com> wrote:
> On Tue, Aug 4, 2015 at 8:59 PM, Robert Haas <robertmhaas@gmail.com> wrote:
>>
>> I'm not entirely happy with the name "nextClearXidElem" but apart from
>> that I'm fairly happy with this version.  We should probably test it
>> to make sure I haven't broken anything;
>
>
> I have verified the patch and it is fine.  I have tested it via manual
> tests; for long pgbench tests, results are quite similar to previous
> versions of patch.
>
> Few changes, I have made in patch:
>
> 1.
>
> +static void
>
> +ProcArrayGroupClearXid(PGPROC *proc, TransactionId latestXid)
>
> +{
>
> + volatile PROC_HDR *procglobal = ProcGlobal;
>
> + uint32 nextidx;
>
> + uint32 wakeidx;
>
> + int extraWaits = -1;
>
> +
>
> + /* We should definitely have an XID to clear. */
>
> + Assert(TransactionIdIsValid(pgxact->xid));
>
>
>
> Here Assert is using pgxact which is wrong.
>
> 2. Made ProcArrayEndTransactionInternal as inline function as
> suggested by you.

OK, committed.

-- 
Robert Haas
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