There's an assertion failure in the test_log03.test_dirty_max, which expects increase to the number of syncs when the dirty_max value is reduced. The machine that failed the test was 'zSeries'.
http://build.wiredtiger.com:8080/job/wiredtiger-test-unit-zseries/2720/
FAIL: test_log03.test_log03.test_dirty_max (subunit.RemotedTestCase)
test_log03.test_log03.test_dirty_max
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_StringException: Traceback (most recent call last):
File "/mnt/workspace/wiredtiger-test-unit-zseries/test/suite/test_log03.py", line 97, in test_dirty_max
self.assertGreater(result, baseline + increase)
File "/usr/lib64/python2.7/unittest/case.py", line 982, in assertGreater
self.fail(self._formatMessage(msg, standardMsg))
File "/usr/lib64/python2.7/unittest/case.py", line 450, in fail
raise self.failureException(msg)
AssertionError: 75 not greater than 75