HDFS-13481. TestRollingFileSystemSinkWithHdfs#testFlushThread: test failed intermittently

(Contributed by Gabor Bota via Daniel Templeton)

Change-Id: I9921981dfa69669fe7912dd2a31ae8b638283204
(cherry picked from commit 87c23ef643393c39e8353ca9f495b0c8f97cdbd9)
(cherry picked from commit 57e41154365aa260ad2b2117779a77196c918eb0)

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/metrics2/sink/RollingFileSystemSinkTestBase.java

@@ -182,7 +182,8 @@ public class RollingFileSystemSinkTestBase {
         .add(prefix + ".sink.mysink0.ignore-error", ignoreErrors)
         .add(prefix + ".sink.mysink0.allow-append", allowAppend)
         .add(prefix + ".sink.mysink0.roll-offset-interval-millis", 0)
-        .add(prefix + ".sink.mysink0.roll-interval", "1h");
+        .add(prefix + ".sink.mysink0.roll-interval", "1h")
+        .add("*.queue.capacity", 2);
 
     if (useSecureParams) {
       builder.add(prefix + ".sink.mysink0.keytab-key", SINK_KEYTAB_FILE_KEY)