Re: Perform streaming logical transactions by background workers and parallel apply

On Wed, Oct 12, 2022 at 7:41 AM wangw(dot)fnst(at)fujitsu(dot)com
<wangw(dot)fnst(at)fujitsu(dot)com> wrote:
>
> On Fri, Oct 7, 2022 at 14:18 PM Hou, Zhijie/侯 志杰 <houzj(dot)fnst(at)cn(dot)fujitsu(dot)com> wrote:
> > Attach the new version patch set which addressed most of the comments.
>
> Rebased the patch set because the new change in HEAD (776e1c8).
>
> Attach the new patch set.
>

+static void
+HandleParallelApplyMessage(ParallelApplyWorkerInfo *winfo, StringInfo msg)
{
...
+ case 'X': /* Terminate, indicating clean exit */
+ {
+ shm_mq_detach(winfo->error_mq_handle);
+ winfo->error_mq_handle = NULL;
+ break;
+ }
...
}

I don't see the use of this message in the patch. If this is not
required by the latest version then we can remove it and its
corresponding handling in parallel_apply_start_worker(). I am
referring to the below code in parallel_apply_start_worker():

+ if (tmp_winfo->error_mq_handle == NULL)
+ {
+ /*
+ * Release the worker information and try next one if the parallel
+ * apply worker exited cleanly.
+ */
+ ParallelApplyWorkersList =
foreach_delete_current(ParallelApplyWorkersList, lc);
+ shm_mq_detach(tmp_winfo->mq_handle);
+ dsm_detach(tmp_winfo->dsm_seg);
+ pfree(tmp_winfo);
+ }

--
With Regards,
Amit Kapila.