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

On Thu, Sep 8, 2022 at 12:21 PM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>
> On Mon, Sep 5, 2022 at 6:34 PM houzj(dot)fnst(at)fujitsu(dot)com
> <houzj(dot)fnst(at)fujitsu(dot)com> wrote:
> >
> > Attach the correct patch set this time.
> >
>
> Few comments on v28-0001*:
> =======================
>

Some suggestions for comments in v28-0001*
1.
+/*
+ * Entry for a hash table we use to map from xid to the parallel apply worker
+ * state.
+ */
+typedef struct ParallelApplyWorkerEntry

Let's change this comment to: "Hash table entry to map xid to the
parallel apply worker state."

2.
+/*
+ * List that stores the information of parallel apply workers that were
+ * started. Newly added worker information will be removed from the list at the
+ * end of the transaction when there are enough workers in the pool. Besides,
+ * exited workers will be removed from the list after being detected.
+ */
+static List *ParallelApplyWorkersList = NIL;

Can we change this to: "A list to maintain the active parallel apply
workers. The information for the new worker is added to the list after
successfully launching it. The list entry is removed at the end of the
transaction if there are already enough workers in the worker pool.
For more information about the worker pool, see comments atop
worker.c. We also remove the entry from the list if the worker is
exited due to some error."

Apart from this, I have added/changed a few other comments in
v28-0001*. Kindly check the attached, if you are fine with it then
please include it in the next version.

--
With Regards,
Amit Kapila.