On Mon, 26 Apr 2021 at 12:49, Amit Kapila <amit.kapil...@gmail.com> wrote: > On Fri, Apr 23, 2021 at 7:18 PM osumi.takami...@fujitsu.com > <osumi.takami...@fujitsu.com> wrote: >> > > The latest patch looks good to me. I have made a minor modification > and added a commit message in the attached. I would like to once again > ask whether anybody else thinks we should backpatch this? Just a > summary for anybody not following this thread: > > This patch fixes the Logical Replication of Truncate in synchronous > commit mode. The Truncate operation acquires an exclusive lock on the > target relation and indexes and waits for logical replication of the > operation to finish at commit. Now because we are acquiring the shared > lock on the target index to get index attributes in pgoutput while > sending the changes for the Truncate operation, it leads to a > deadlock. > > Actually, we don't need to acquire a lock on the target index as we > build the cache entry using a historic snapshot and all the later > changes are absorbed while decoding WAL. So, we wrote a special > purpose function for logical replication to get a bitmap of replica > identity attribute numbers where we get that information without > locking the target index. > > We are planning not to backpatch this as there doesn't seem to be any > field complaint about this issue since it was introduced in commit > 5dfd1e5a in v11.
+1 for apply only on HEAD. -- Regrads, Japin Li. ChengDu WenWu Information Technology Co.,Ltd.
