The test failed on branch=release-20.1, cloud=gce:
test artifacts and logs in: /home/agent/work/.go/src/github.com/cockroachdb/cockroach/artifacts/tpccbench/nodes=6/cpu=16/multi-az/run_1
	cluster.go:2628,tpcc.go:735,tpcc.go:576,test_runner.go:749: monitor failure: unexpected node event: 2: dead
		(1) attached stack trace
		  | main.(*monitor).WaitE
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/pkg/cmd/roachtest/cluster.go:2616
		  | main.(*monitor).Wait
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/pkg/cmd/roachtest/cluster.go:2624
		  | main.runTPCCBench
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/pkg/cmd/roachtest/tpcc.go:735
		  | main.registerTPCCBenchSpec.func1
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/pkg/cmd/roachtest/tpcc.go:576
		  | main.(*testRunner).runTest.func2
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/pkg/cmd/roachtest/test_runner.go:749
		  | runtime.goexit
		  | 	/usr/local/go/src/runtime/asm_amd64.s:1374
		Wraps: (2) monitor failure
		Wraps: (3) unexpected node event: 2: dead
		Error types: (1) *withstack.withStack (2) *errutil.withMessage (3) *errors.errorString