Dmitriy Vyukov
4e5086b993
runtime: improve Linux mutex
...
The implementation is hybrid active/passive spin/blocking mutex.
The design minimizes amount of context switches and futex calls.
The idea is that all critical sections in runtime are intentially
small, so pure blocking mutex behaves badly causing
a lot of context switches, thread parking/unparking and kernel calls.
Note that some synthetic benchmarks become somewhat slower,
that's due to increased contention on other data structures,
it should not affect programs that do any real work.
On 2 x Intel E5620, 8 HT cores, 2.4GHz
benchmark old ns/op new ns/op delta
BenchmarkSelectContended 521.00 503.00 -3.45%
BenchmarkSelectContended-2 661.00 320.00 -51.59%
BenchmarkSelectContended-4 1139.00 629.00 -44.78%
BenchmarkSelectContended-8 2870.00 878.00 -69.41%
BenchmarkSelectContended-16 5276.00 818.00 -84.50%
BenchmarkChanContended 112.00 103.00 -8.04%
BenchmarkChanContended-2 631.00 174.00 -72.42%
BenchmarkChanContended-4 682.00 272.00 -60.12%
BenchmarkChanContended-8 1601.00 520.00 -67.52%
BenchmarkChanContended-16 3100.00 372.00 -88.00%
BenchmarkChanSync 253.00 239.00 -5.53%
BenchmarkChanSync-2 5030.00 4648.00 -7.59%
BenchmarkChanSync-4 4826.00 4694.00 -2.74%
BenchmarkChanSync-8 4778.00 4713.00 -1.36%
BenchmarkChanSync-16 5289.00 4710.00 -10.95%
BenchmarkChanProdCons0 273.00 254.00 -6.96%
BenchmarkChanProdCons0-2 599.00 400.00 -33.22%
BenchmarkChanProdCons0-4 1168.00 659.00 -43.58%
BenchmarkChanProdCons0-8 2831.00 1057.00 -62.66%
BenchmarkChanProdCons0-16 4197.00 1037.00 -75.29%
BenchmarkChanProdCons10 150.00 140.00 -6.67%
BenchmarkChanProdCons10-2 607.00 268.00 -55.85%
BenchmarkChanProdCons10-4 1137.00 404.00 -64.47%
BenchmarkChanProdCons10-8 2115.00 828.00 -60.85%
BenchmarkChanProdCons10-16 4283.00 855.00 -80.04%
BenchmarkChanProdCons100 117.00 110.00 -5.98%
BenchmarkChanProdCons100-2 558.00 218.00 -60.93%
BenchmarkChanProdCons100-4 722.00 287.00 -60.25%
BenchmarkChanProdCons100-8 1840.00 431.00 -76.58%
BenchmarkChanProdCons100-16 3394.00 448.00 -86.80%
BenchmarkChanProdConsWork0 2014.00 1996.00 -0.89%
BenchmarkChanProdConsWork0-2 1207.00 1127.00 -6.63%
BenchmarkChanProdConsWork0-4 1913.00 611.00 -68.06%
BenchmarkChanProdConsWork0-8 3016.00 949.00 -68.53%
BenchmarkChanProdConsWork0-16 4320.00 1154.00 -73.29%
BenchmarkChanProdConsWork10 1906.00 1897.00 -0.47%
BenchmarkChanProdConsWork10-2 1123.00 1033.00 -8.01%
BenchmarkChanProdConsWork10-4 1076.00 571.00 -46.93%
BenchmarkChanProdConsWork10-8 2748.00 1096.00 -60.12%
BenchmarkChanProdConsWork10-16 4600.00 1105.00 -75.98%
BenchmarkChanProdConsWork100 1884.00 1852.00 -1.70%
BenchmarkChanProdConsWork100-2 1235.00 1146.00 -7.21%
BenchmarkChanProdConsWork100-4 1217.00 619.00 -49.14%
BenchmarkChanProdConsWork100-8 1534.00 509.00 -66.82%
BenchmarkChanProdConsWork100-16 4126.00 918.00 -77.75%
BenchmarkSyscall 34.40 33.30 -3.20%
BenchmarkSyscall-2 160.00 121.00 -24.38%
BenchmarkSyscall-4 131.00 136.00 +3.82%
BenchmarkSyscall-8 139.00 131.00 -5.76%
BenchmarkSyscall-16 161.00 168.00 +4.35%
BenchmarkSyscallWork 950.00 950.00 +0.00%
BenchmarkSyscallWork-2 481.00 480.00 -0.21%
BenchmarkSyscallWork-4 268.00 270.00 +0.75%
BenchmarkSyscallWork-8 156.00 169.00 +8.33%
BenchmarkSyscallWork-16 188.00 184.00 -2.13%
BenchmarkSemaSyntNonblock 36.40 35.60 -2.20%
BenchmarkSemaSyntNonblock-2 81.40 45.10 -44.59%
BenchmarkSemaSyntNonblock-4 126.00 108.00 -14.29%
BenchmarkSemaSyntNonblock-8 112.00 112.00 +0.00%
BenchmarkSemaSyntNonblock-16 110.00 112.00 +1.82%
BenchmarkSemaSyntBlock 35.30 35.30 +0.00%
BenchmarkSemaSyntBlock-2 118.00 124.00 +5.08%
BenchmarkSemaSyntBlock-4 105.00 108.00 +2.86%
BenchmarkSemaSyntBlock-8 101.00 111.00 +9.90%
BenchmarkSemaSyntBlock-16 112.00 118.00 +5.36%
BenchmarkSemaWorkNonblock 810.00 811.00 +0.12%
BenchmarkSemaWorkNonblock-2 476.00 414.00 -13.03%
BenchmarkSemaWorkNonblock-4 238.00 228.00 -4.20%
BenchmarkSemaWorkNonblock-8 140.00 126.00 -10.00%
BenchmarkSemaWorkNonblock-16 117.00 116.00 -0.85%
BenchmarkSemaWorkBlock 810.00 811.00 +0.12%
BenchmarkSemaWorkBlock-2 454.00 466.00 +2.64%
BenchmarkSemaWorkBlock-4 243.00 241.00 -0.82%
BenchmarkSemaWorkBlock-8 145.00 137.00 -5.52%
BenchmarkSemaWorkBlock-16 132.00 123.00 -6.82%
BenchmarkContendedSemaphore 123.00 102.00 -17.07%
BenchmarkContendedSemaphore-2 34.80 34.90 +0.29%
BenchmarkContendedSemaphore-4 34.70 34.80 +0.29%
BenchmarkContendedSemaphore-8 34.70 34.70 +0.00%
BenchmarkContendedSemaphore-16 34.80 34.70 -0.29%
BenchmarkMutex 26.80 26.00 -2.99%
BenchmarkMutex-2 108.00 45.20 -58.15%
BenchmarkMutex-4 103.00 127.00 +23.30%
BenchmarkMutex-8 109.00 147.00 +34.86%
BenchmarkMutex-16 102.00 152.00 +49.02%
BenchmarkMutexSlack 27.00 26.90 -0.37%
BenchmarkMutexSlack-2 149.00 165.00 +10.74%
BenchmarkMutexSlack-4 121.00 209.00 +72.73%
BenchmarkMutexSlack-8 101.00 158.00 +56.44%
BenchmarkMutexSlack-16 97.00 129.00 +32.99%
BenchmarkMutexWork 792.00 794.00 +0.25%
BenchmarkMutexWork-2 407.00 409.00 +0.49%
BenchmarkMutexWork-4 220.00 209.00 -5.00%
BenchmarkMutexWork-8 267.00 160.00 -40.07%
BenchmarkMutexWork-16 315.00 300.00 -4.76%
BenchmarkMutexWorkSlack 792.00 793.00 +0.13%
BenchmarkMutexWorkSlack-2 406.00 404.00 -0.49%
BenchmarkMutexWorkSlack-4 225.00 212.00 -5.78%
BenchmarkMutexWorkSlack-8 268.00 136.00 -49.25%
BenchmarkMutexWorkSlack-16 300.00 300.00 +0.00%
BenchmarkRWMutexWrite100 27.10 27.00 -0.37%
BenchmarkRWMutexWrite100-2 33.10 40.80 +23.26%
BenchmarkRWMutexWrite100-4 113.00 88.10 -22.04%
BenchmarkRWMutexWrite100-8 119.00 95.30 -19.92%
BenchmarkRWMutexWrite100-16 148.00 109.00 -26.35%
BenchmarkRWMutexWrite10 29.60 29.40 -0.68%
BenchmarkRWMutexWrite10-2 111.00 61.40 -44.68%
BenchmarkRWMutexWrite10-4 270.00 208.00 -22.96%
BenchmarkRWMutexWrite10-8 204.00 185.00 -9.31%
BenchmarkRWMutexWrite10-16 261.00 190.00 -27.20%
BenchmarkRWMutexWorkWrite100 1040.00 1036.00 -0.38%
BenchmarkRWMutexWorkWrite100-2 593.00 580.00 -2.19%
BenchmarkRWMutexWorkWrite100-4 470.00 365.00 -22.34%
BenchmarkRWMutexWorkWrite100-8 468.00 289.00 -38.25%
BenchmarkRWMutexWorkWrite100-16 604.00 374.00 -38.08%
BenchmarkRWMutexWorkWrite10 951.00 951.00 +0.00%
BenchmarkRWMutexWorkWrite10-2 1001.00 928.00 -7.29%
BenchmarkRWMutexWorkWrite10-4 1555.00 1006.00 -35.31%
BenchmarkRWMutexWorkWrite10-8 2085.00 1171.00 -43.84%
BenchmarkRWMutexWorkWrite10-16 2082.00 1614.00 -22.48%
R=rsc, iant, msolo, fw, iant
CC=golang-dev
https://golang.org/cl/4711045
2011-07-29 12:44:06 -04:00
Russ Cox
1f2234633f
runtime: fix arm build
...
R=adg, dfc, r
CC=golang-dev
https://golang.org/cl/4296042
2011-03-25 12:30:49 -04:00
Russ Cox
079cbddbd8
arm: fix signal handler
...
R=ken2
CC=golang-dev
https://golang.org/cl/2670042
2010-10-26 01:32:36 +02:00
Russ Cox
649aab835f
runtime: add mmap of null page just in case
...
R=r, iant, robert.swiecki, rsc1
CC=golang-dev
https://golang.org/cl/1904044
2010-09-28 20:30:01 -04:00
Russ Cox
5963dbac08
runtime: turn divide by zero, nil dereference into panics
...
tested on linux/amd64, linux/386, linux/arm, darwin/amd64, darwin/386.
freebsd untested; will finish in a separate CL.
for now all the panics are errorStrings.
richer structures can be added as necessary
once the mechanism is shaked out.
R=r
CC=golang-dev
https://golang.org/cl/906041
2010-04-08 18:15:30 -07:00
Russ Cox
6c196015e0
runtime: various arm fixes
...
* correct symbol table size
* do not reorder functions in output
* traceback
* signal handling
* use same code for go + defer
* handle leaf functions in symbol table
R=kaib, dpx
CC=golang-dev
https://golang.org/cl/884041
2010-04-05 12:51:09 -07:00
Rob Pike
d90e7cbac6
mv src/lib to src/pkg
...
tests: all.bash passes, gobuild still works, godoc still works.
R=rsc
OCL=30096
CL=30102
2009-06-09 09:53:44 -07:00
