Same patch, commit message added. Adding to commitfest. -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
>From 2cbe6fe5ac7617e424a63b820a6a2c83b712bab5 Mon Sep 17 00:00:00 2001 From: Alvaro Herrera <alvhe...@alvh.no-ip.org> Date: Thu, 6 Dec 2018 17:30:58 -0300 Subject: [PATCH] Optimize CancelVirtualTransaction a little bit
When scanning the list of virtual transactions looking for one particular vxid, we cancel the transaction *and* break out of the loop only if both backendId and localTransactionId matches us. The canceling part is okay, but limiting the break to that case is pointless: if we found the correct backendId, there cannot be any other entry with the same backendId. Rework the loop so that we break out of it if backendId matches even if the localTransactionId part doesn't. Discussion: https://postgr.es/m/20180629170512.d6kof6l6uu3qqpd6@alvherre.pgsql --- src/backend/storage/ipc/procarray.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c index dc7e875680..5ed588d9be 100644 --- a/src/backend/storage/ipc/procarray.c +++ b/src/backend/storage/ipc/procarray.c @@ -2683,18 +2683,20 @@ CancelVirtualTransaction(VirtualTransactionId vxid, ProcSignalReason sigmode) GET_VXID_FROM_PGPROC(procvxid, *proc); - if (procvxid.backendId == vxid.backendId && - procvxid.localTransactionId == vxid.localTransactionId) + if (procvxid.backendId == vxid.backendId) { - proc->recoveryConflictPending = true; - pid = proc->pid; - if (pid != 0) + if (procvxid.localTransactionId == vxid.localTransactionId) { - /* - * Kill the pid if it's still here. If not, that's what we - * wanted so ignore any errors. - */ - (void) SendProcSignal(pid, sigmode, vxid.backendId); + proc->recoveryConflictPending = true; + pid = proc->pid; + if (pid != 0) + { + /* + * Kill the pid if it's still here. If not, that's what we + * wanted so ignore any errors. + */ + (void) SendProcSignal(pid, sigmode, vxid.backendId); + } } break; } -- 2.11.0
