.

bench/nocasgstatus/5a45a157/B/tip+gc.txt.30

+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 1000000	     41128 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40975 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40565 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40607 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40731 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40563 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40570 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40431 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40665 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41053 ns/op
+PASS
+ok  	_/home/kirr/src/tools/go/go/test/bench/go1	412.788s

bench/nocasgstatus/5a45a157/B/tip+patch+gc.txt.30

+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 1000000	     40701 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40395 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40377 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40508 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40272 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40529 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40560 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40503 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40416 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40408 ns/op
+PASS
+ok  	_/home/kirr/src/tools/go/go/test/bench/go1	410.134s

bench/nocasgstatus/5a45a157/B2/tip+gc.txt.30

+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 1000000	     41923 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41732 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41734 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     42162 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41459 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41454 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41442 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41670 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41663 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41718 ns/op
+PASS
+ok  	_/home/kirr/src/tools/go/go/test/bench/go1	422.559s

bench/nocasgstatus/5a45a157/B2/tip+patch+gc.txt.100

+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 3000000	     40276 ns/op
+PASS
+ok  	_/home/kirr/src/tools/go/go/test/bench/go1	163.035s

bench/nocasgstatus/5a45a157/B2/tip+patch+gc.txt.30

+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 1000000	     40579 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40426 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40203 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40238 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40299 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40231 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40208 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40148 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40112 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40342 ns/op
+PASS
+ok  	_/home/kirr/src/tools/go/go/test/bench/go1	408.259s

bench/nocasgstatus/5a45a157/B3/tip+gc.txt.50

+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 2000000	     41035 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41360 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41223 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41427 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41120 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41350 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41290 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41344 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41479 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41572 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41100 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41131 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41520 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41243 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41514 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41190 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41156 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41493 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41060 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41475 ns/op
+PASS
+ok  	_/home/kirr/src/tools/go/go/test/bench/go1	2487.164s

bench/nocasgstatus/5a45a157/B3/tip+gc.txt.50-many

+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 2000000	     41070 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41044 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41262 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41000 ns/op
+BenchmarkHTTPClientServer-4   	*** Test killed with quit: ran too long (10m0s).
+FAIL	_/home/kirr/src/tools/go/go/test/bench/go1	600.026s
+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 2000000	     41726 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41779 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41400 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41422 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41780 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41597 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41806 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41424 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41769 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41423 ns/op
+BenchmarkHTTPClientServer-4   	*** Test killed with quit: ran too long (21m0s).
+FAIL	_/home/kirr/src/tools/go/go/test/bench/go1	1260.025s
+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 2000000	     41035 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41360 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41223 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41427 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41120 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41350 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41290 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41344 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41479 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41572 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41100 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41131 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41520 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41243 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41514 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41190 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41156 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41493 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41060 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     41475 ns/op
+PASS
+ok  	_/home/kirr/src/tools/go/go/test/bench/go1	2487.164s

bench/nocasgstatus/5a45a157/B3/tip+patch+gc.txt.50

+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 2000000	     40964 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40577 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40619 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40653 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40813 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40666 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40501 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40991 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40434 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40873 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40576 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40832 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40497 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40887 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40647 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40418 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40853 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40839 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40678 ns/op
+BenchmarkHTTPClientServer-4   	 2000000	     40656 ns/op
+PASS
+ok  	_/home/kirr/src/tools/go/go/test/bench/go1	2451.943s

bench/nocasgstatus/5a45a157/B4/tip+gc.txt.30

+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 1000000	     41280 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41120 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41094 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40584 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40854 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41020 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41012 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40925 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40699 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40884 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40906 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40803 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40991 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40832 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41232 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41035 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40653 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40628 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41168 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     41215 ns/op
+PASS
+ok  	_/home/kirr/src/tools/go/go/test/bench/go1	828.744s

bench/nocasgstatus/5a45a157/B4/tip+patch+gc.txt.30

+goos: linux
+goarch: amd64
+BenchmarkHTTPClientServer-4   	 1000000	     40569 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40671 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40280 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40179 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40294 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40706 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40276 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40264 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40974 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40193 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40217 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40394 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40188 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40489 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40403 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40300 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40489 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40292 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40366 ns/op
+BenchmarkHTTPClientServer-4   	 1000000	     40408 ns/op
+PASS
+ok  	_/home/kirr/src/tools/go/go/test/bench/go1	817.679s

bench/nocasgstatus/nocasgstatus.patch

+https://github.com/golang/go/issues/19563#issuecomment-287816669
+diff --git a/src/runtime/proc.go b/src/runtime/proc.go
+index 159a9bd4bc..1538274c77 100644
+--- a/src/runtime/proc.go
++++ b/src/runtime/proc.go
+@@ -749,6 +749,17 @@ func casgstatus(gp *g, oldval, newval uint32) {
+                throw("casgstatus")
+        }
+ 
++       if gcphase == _GCoff {
++               if gp.atomicstatus != oldval {
++                       throw("bad old status")
++               }
++               gp.atomicstatus = newval
++               if newval == _Grunning {
++                       gp.gcscanvalid = false
++               }
++               return
++       }
++
+        // See http://golang.org/cl/21503 for justification of the yield delay.
+        const yieldDelay = 5 * 1000
+        var nextYield int64