Re: lastOverflowedXid does not handle transaction ID wraparound

> 21 окт. 2021 г., в 09:01, Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com> написал(а):
>
> If the discussion so far is correct, the following diff will fix the
> issue.
>
> diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c
> index bd3c7a47fe..19682b73ec 100644
> --- a/src/backend/storage/ipc/procarray.c
> +++ b/src/backend/storage/ipc/procarray.c
> @@ -4463,6 +4463,12 @@ ExpireOldKnownAssignedTransactionIds(TransactionId xid)
> {
> LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE);
> KnownAssignedXidsRemovePreceding(xid);
> + /*
> + * reset lastOverflowedXid if we know transactions that have been possiblly
> + * running are being gone.
> + */
> + if (TransactionIdPrecedes(procArray->lastOverflowedXid, xid))
> + procArray->lastOverflowedXid = InvalidTransactionId;
> LWLockRelease(ProcArrayLock);
> }

The patch seems correct bugfix to me. The only question I have: is it right place from modularity standpoint? procArray->lastOverflowedXid is not a part of KnownAssignedTransactionIds?

Best regards, Andrey Borodin.