Horton

Re: standby recovery fails (tablespace related) (tentative patch and discussion)

Michael Paquier <michael@paquier.xyz>

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From: Michael Paquier <michael@paquier.xyz>
To: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>
Cc: pguo@pivotal.io, apraveen@pivotal.io, pgsql-hackers@postgresql.org
Date: 2019-04-23T02:34:38Z
Lists: pgsql-hackers 
On Mon, Apr 22, 2019 at 09:19:33PM +0900, Kyotaro HORIGUCHI wrote:
> The attached exercises this sequence, needing some changes in
> PostgresNode.pm and RecursiveCopy.pm to allow tablespaces.

+    # Check for symlink -- needed only on source dir
+    # (note: this will fall through quietly if file is already gone)
+    if (-l $srcpath)
+    {
+        croak "Cannot operate on symlink \"$srcpath\""
+          if ($srcpath !~ /\/(pg_tblspc\/[0-9]+)$/);
+
+        # We have mapped tablespaces. Copy them individually
+        my $linkname = $1;
+        my $tmpdir = TestLib::tempdir;
+        my $dstrealdir = TestLib::real_dir($tmpdir);
+        my $srcrealdir = readlink($srcpath);
+
+        opendir(my $dh, $srcrealdir);
+        while (readdir $dh)
+        {
+            next if (/^\.\.?$/);
+            my $spath = "$srcrealdir/$_";
+            my $dpath = "$dstrealdir/$_";
+
+            copypath($spath, $dpath);
+        }
+        closedir $dh;
+
+        symlink $dstrealdir, $destpath;
+        return 1;
+    }

The same stuff is proposed here:
https://www.postgresql.org/message-id/CAGRcZQUxd9YOfifOKXOfJ+Fp3JdpoeKCzt+zH_PRMNaaDaExdQ@mail.gmail.com

So there is a lot of demand for making the recursive copy more skilled
at handling symlinks for tablespace tests, and I'd like to propose to
do something among those lines for the tests on HEAD, presumably for
v12 and not v13 as we are talking about a bug fix here?  I am not sure
yet which one of the proposals is better than the other though.
--
Michael

Commits

  1. Improve recently-added test reliability

  2. Fix new recovery test for log_error_verbosity=verbose case

  3. Fix test instability

  4. Fix replay of create database records on standby

  5. Allow "in place" tablespaces.

  6. Fix get_dirent_type() for Windows junction points.

  7. Revert "Fix replay of create database records on standby"

  8. Add end-to-end testing of pg_basebackup's tar-format output.

  9. Make DROP DATABASE command generate less WAL records.

  10. Consolidate methods for translating a Perl path to a Windows path.