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

Some minor review comments for v58-0001

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.../replication/logical/applyparallelworker.c

1. pa_can_start

+ /*
+ * Don't start a new parallel worker if user has set skiplsn as it's
+ * possible that user want to skip the streaming transaction. For streaming
+ * transaction, we need to serialize the transaction to a file so that we
+ * can get the last LSN of the transaction to judge whether to skip before
+ * starting to apply the change.
+ */
+ if (!XLogRecPtrIsInvalid(MySubscription->skiplsn))
+ return false;

"that user want" -> "that they want"

"For streaming transaction," -> "For streaming transactions,"

~~~

2. pa_free_worker_info

+ /* Remove from the worker pool. */
+ ParallelApplyWorkerPool = list_delete_ptr(ParallelApplyWorkerPool,
+ winfo);

Unnecessary wrapping

~~~

3. pa_set_stream_apply_worker

+/*
+ * Set the worker that required to apply the current streaming transaction.
+ */
+void
+pa_set_stream_apply_worker(ParallelApplyWorkerInfo *winfo)
+{
+ stream_apply_worker = winfo;
+}

Comment wording seems wrong.

======

src/include/replication/worker_internal.h

4. ParallelApplyWorkerShared

+ * XactLastCommitEnd from the parallel apply worker. This is required to
+ * update the lsn_mappings by leader worker.
+ */
+ XLogRecPtr last_commit_end;
+} ParallelApplyWorkerShared;

"This is required to update the lsn_mappings by leader worker." -->
did you mean "This is required by the leader worker so it can update
the lsn_mappings." ??

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Kind Regards,
Peter Smith.
Fujitsu Australia