From: Martin Schwenke <martin@meltin.net>
Date: Tue, 3 Jan 2017 22:53:54 +0000 (+1100)
Subject: ctdb-scripts: Avoid no-op "ctdb ptrans" call
X-Git-Tag: talloc-2.1.12~312
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=2ad1604c2baa547ad881dc75cbb47722d0af651b;p=thirdparty%2Fsamba.git

ctdb-scripts: Avoid no-op "ctdb ptrans" call

This causes unnecessary g_lock activity and overhead.

This could be optimised in ctdb.c:control_ptrans().  However, that
makes the code more complex.  Let's only do that if we get more
potentially no-op uses.

Note no optimisation is needed in the "notify" case because there is
already an early exit if there are no items.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>
---

diff --git a/ctdb/config/statd-callout b/ctdb/config/statd-callout
index 38f847b1d9b..e2bac639e4b 100755
--- a/ctdb/config/statd-callout
+++ b/ctdb/config/statd-callout
@@ -91,10 +91,14 @@ case "$1" in
                 printf "/statd-state@%s@/p\n", ip }')
 	# Intentional multi-word expansion for multiple files
 	# shellcheck disable=SC2086
-        if sed -n "$sed_expr" $files | $CTDB ptrans "ctdb.tdb" ; then
-            rm $files
+	items=$(sed -n "$sed_expr" $files)
+	if [ -n "$items" ] ; then
+		if echo "$items"  | $CTDB ptrans "ctdb.tdb" ; then
+			# shellcheck disable=SC2086
+			rm $files
+		fi
 	fi
-        ;;
+	;;
 
     notify)
 	# we must restart the lockmanager (on all nodes) so that we get