runtime.newproc/ready are deliberately sloppy about waking new M's,
they only ensure that there is at least 1 spinning M.
Currently to compensate for that, schedule() checks if the current P
has local work and there are no spinning M's, it wakes up another one.
It does not work if goroutines do not call schedule.
With this change a spinning M wakes up another M when it finds work to do.
It's also not ideal, but it fixes the underutilization.
A proper check would require to know the exact number of runnable G's,
but it's too expensive to maintain.
Fixes#5586.
This is reincarnation of cl/9776044 with the bug fixed.
The bug was due to code added after cl/9776044 was created:
if(tick - (((uint64)tick*0x4325c53fu)>>36)*61 == 0 && runtime·sched.runqsize > 0) {
runtime·lock(&runtime·sched);
gp = globrunqget(m->p, 1);
runtime·unlock(&runtime·sched);
}
If M gets gp from global runq here, it does not reset m->spinning.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/10743044
Currently it crashes as follows:
fatal error: unknown pc
...
goroutine 71698 [runnable]:
runtime.racegoend()
src/pkg/runtime/race.c:171
runtime.goexit()
src/pkg/runtime/proc.c:1276 +0x9
created by runtime_test.testConcurrentReadsAfterGrowth
src/pkg/runtime/map_test.go:264 +0x332
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/10674047
Merging a couple of CLs into one, since they collided in my client
and I'm lazy.
1) Fix up output in "go test -cover" case.
We need to tell the testing package the name of the package being tested
and the name of the package being covered. It can then sort out the report.
2) Filter out the _test.go files from coverage processing. We want to measure
what the tests cover, not what's covered in the tests,
The coverage for encoding/gob goes from 82.2% to 88.4%.
There may be a cleaner way to do this - suggestions welcome - but ça suffit.
Fixes#5810.
R=rsc
CC=golang-dev
https://golang.org/cl/10868047
Part 3 of several.
* Linux has grown a SetsockoptByte.
* SetsockoptIPMreqn is handled directly by syscall_linux.go and syscall_freebsd.go.
R=golang-dev, mikioh.mikioh, r, bradfitz
CC=golang-dev
https://golang.org/cl/10775043
The lzw.NewReader doc comment says, "It is the caller's responsibility
to call Close on the ReadCloser when finished reading."
Thanks to Andrew Bonventre for noticing this.
R=r, dsymonds, adg
CC=andybons, golang-dev
https://golang.org/cl/10821043
ReadMIMEHeader is used by net/http, net/mail, and
mime/multipart.
Don't do so many small allocations. Calculate up front
how much we'll probably need.
benchmark old ns/op new ns/op delta
BenchmarkReadMIMEHeader 8433 7467 -11.45%
benchmark old allocs new allocs delta
BenchmarkReadMIMEHeader 23 14 -39.13%
benchmark old bytes new bytes delta
BenchmarkReadMIMEHeader 1705 1343 -21.23%
R=golang-dev, r, iant, adg
CC=golang-dev
https://golang.org/cl/8179043
This does not include AES-GCM yet. Also, it assumes that the handshake and
certificate signature hash are always SHA-256, which is true of the ciphersuites
that we currently support.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/10762044
using m->tls[0] to save ucontext pointer is not re-entry safe, and
the old code didn't set it before the early return when signal is
received on non-Go threads.
so misc/cgo/test used to hang when testing issue 5337.
R=golang-dev, bradfitz, rsc
CC=golang-dev
https://golang.org/cl/10076045
When deleting a timer, a panic due to nil deref
would leave a lock held, possibly leading to a deadlock
in a defer. Instead return false on a nil timer.
Fixes#5745.
R=golang-dev, daniel.morsing, dvyukov, rsc, iant
CC=golang-dev
https://golang.org/cl/10373047
This CL provides stable in-place sorting by use of
bottom up merge sort with in-place merging done by
the SymMerge algorithm from P.-S. Kim and A. Kutzner.
The additional space needed for stable sorting (in the form of
stack space) is logarithmic in the inputs size n.
Number of calls to Less and Swap grow like O(n * log n) and
O(n * log n * log n):
Stable sorting random data uses significantly more calls
to Swap than the unstable quicksort implementation (5 times more
on n=100, 10 times more on n=1e4 and 23 times more on n=1e8).
The number of calls to Less is practically the same for Sort and
Stable.
Stable sorting 1 million random integers takes 5 times longer
than using Sort.
BenchmarkSortString1K 50000 328662 ns/op
BenchmarkStableString1K 50000 380231 ns/op 1.15 slower
BenchmarkSortInt1K 50000 157336 ns/op
BenchmarkStableInt1K 50000 191167 ns/op 1.22 slower
BenchmarkSortInt64K 1000 14466297 ns/op
BenchmarkStableInt64K 500 16190266 ns/op 1.12 slower
BenchmarkSort1e2 200000 64923 ns/op
BenchmarkStable1e2 50000 167128 ns/op 2.57 slower
BenchmarkSort1e4 1000 14540613 ns/op
BenchmarkStable1e4 100 58117289 ns/op 4.00 slower
BenchmarkSort1e6 5 2429631508 ns/op
BenchmarkStable1e6 1 12077036952 ns/op 4.97 slower
R=golang-dev, bradfitz, iant, 0xjnml, rsc
CC=golang-dev
https://golang.org/cl/9612044
There are various problems, and both Dmitriy and I
will be away for the next week. Make the runtime a bit
more stable while we're gone.
R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/10848043
fn can clearly hold a closure in memory.
argp/pc point into stack and so can hold
in memory a block that was previously
a large stack serment.
R=golang-dev, dave, rsc
CC=golang-dev
https://golang.org/cl/10784043
Depending on net/http means depending on cgo.
When the tree is in a shaky state it's nice to see sync/atomic
pass even if cgo or net causes broken binaries.
R=golang-dev, dave, r
CC=golang-dev
https://golang.org/cl/10753044
After loading a frame of a GIF, check that each pixel
is inside the frame's palette.
Fixes#5401.
R=nigeltao, r
CC=golang-dev
https://golang.org/cl/10597043
On amd64 the frames are very close to the limit for a
nosplit (textflag 7) function, in part because the C compiler
does not make any attempt to reclaim space allocated for
completely registerized variables. Avoid a few short-lived
variables to reclaim two words.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/10758043
Currently it replaces GOGCTRACE env var (GODEBUG=gctrace=1).
The plan is to extend it with other type of debug tracing,
e.g. GODEBUG=gctrace=1,schedtrace=100.
R=rsc
CC=bradfitz, daniel.morsing, gobot, golang-dev
https://golang.org/cl/10026045
The last patch for preemptive scheduler,
with this change stoptheworld issues preemption
requests every 100us.
Update #543.
R=golang-dev, daniel.morsing, rsc
CC=golang-dev
https://golang.org/cl/10264044
On x86 it is a few words lower on the stack than m->morebuf.sp
so it is a more precise check. Enabling the check requires recording
a valid gp->sched in reflect.call too. This is a good thing in general,
since it will make stack traces during reflect.call work better, and it
may be useful for preemption too.
R=dvyukov
CC=golang-dev
https://golang.org/cl/10709043
runtime.entersyscall() sets g->status = Gsyscall,
then calls runtime.lock() which causes stack split.
runtime.newstack() resets g->status to Grunning.
This will lead to crash during GC (world is not stopped) or GC will scan stack incorrectly.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/10696043
Also use 2048-bit RSA keys as default in generate_cert.go,
as recommended by the NIST.
R=golang-dev, rsc, bradfitz
CC=golang-dev
https://golang.org/cl/10676043
On my 64-bit machine, despite being 32-bit code, fixed-base
multiplications are 7.1x faster and arbitary multiplications are 2.6x
faster.
It is difficult to review this change. However, the code is essentially
the same as code that has been open-sourced in Chromium. There it has
been successfully performing P-256 operations for several months on
many machines so the arithmetic of the code should be sound.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/10551044
Failure on bot:
http://build.golang.org/log/f4c648906e1289ec2237c1d0880fb1a8b1852a08
««« original CL description
runtime: fix CPU underutilization
runtime.newproc/ready are deliberately sloppy about waking new M's,
they only ensure that there is at least 1 spinning M.
Currently to compensate for that, schedule() checks if the current P
has local work and there are no spinning M's, it wakes up another one.
It does not work if goroutines do not call schedule.
With this change a spinning M wakes up another M when it finds work to do.
It's also not ideal, but it fixes the underutilization.
A proper check would require to know the exact number of runnable G's,
but it's too expensive to maintain.
Fixes#5586.
R=rsc
TBR=rsc
CC=gobot, golang-dev
https://golang.org/cl/9776044
»»»
R=golang-dev
CC=golang-dev
https://golang.org/cl/10692043
runtime.newproc/ready are deliberately sloppy about waking new M's,
they only ensure that there is at least 1 spinning M.
Currently to compensate for that, schedule() checks if the current P
has local work and there are no spinning M's, it wakes up another one.
It does not work if goroutines do not call schedule.
With this change a spinning M wakes up another M when it finds work to do.
It's also not ideal, but it fixes the underutilization.
A proper check would require to know the exact number of runnable G's,
but it's too expensive to maintain.
Fixes#5586.
R=rsc
CC=gobot, golang-dev
https://golang.org/cl/9776044
Current code can print more arguments than necessary
and also incorrectly prints "...".
Update #5723.
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/10689043
