KUDU-1282. Add more logging on slow thread startup
KUDU-1282. Add more logging on slow thread startup

We've seen a few cases where threads are taking >500ms to start,
but it's not clear whether it's the pthread call itself, or
something to do with our Kudu threading wrapper.

This patch adds some more log messages for slow thread startup
to try to pinpoint the issue.

Change-Id: I89b2446f8107e7f1647f079f9ab97fd2d57ee921
Reviewed-on: http://gerrit.cloudera.org:8080/1651
Tested-by: Internal Jenkins
Reviewed-by: Jean-Daniel Cryans

cloudera/kudu,InspurUSA/kudu,InspurUSA/kudu,InspurUSA/kudu,andrwng/kudu,cloudera/kudu,andrwng/kudu,EvilMcJerkface/kudu,InspurUSA/kudu,cloudera/kudu,EvilMcJerkface/kudu,EvilMcJerkface/kudu,EvilMcJerkface/kudu,helifu/kudu,helifu/kudu,andrwng/kudu,InspurUSA/kudu,cloudera/kudu,InspurUSA/kudu,cloudera/kudu,helifu/kudu,helifu/kudu,andrwng/kudu,cloudera/kudu,helifu/kudu,EvilMcJerkface/kudu,InspurUSA/kudu,InspurUSA/kudu,InspurUSA/kudu,EvilMcJerkface/kudu,andrwng/kudu,andrwng/kudu,helifu/kudu,helifu/kudu,cloudera/kudu,andrwng/kudu,andrwng/kudu,EvilMcJerkface/kudu,EvilMcJerkface/kudu,andrwng/kudu,cloudera/kudu,cloudera/kudu,helifu/kudu,helifu/kudu,EvilMcJerkface/kudu