unstable test TestGlobalMemoryTuner

[hawkingrei]

Bug Report

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==================== Test output for //util/gctuner:gctuner_test (shard 3 of 5):

=== RUN   TestGlobalMemoryTuner

    memory_limit_tuner_test.go:97: 

        	Error Trace:	util/gctuner/memory_limit_tuner_test.go:97

        	Error:      	Should be true

        	Test:       	TestGlobalMemoryTuner

    memory_limit_tuner_test.go:71: 

        	Error Trace:	util/gctuner/memory_limit_tuner_test.go:71

        	            				GOROOT/src/runtime/panic.go:540

        	            				GOROOT/src/testing/testing.go:980

        	            				util/gctuner/memory_limit_tuner_test.go:97

        	Error:      	Condition never satisfied

        	Test:       	TestGlobalMemoryTuner

--- FAIL: TestGlobalMemoryTuner (6.14s)

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