Commit Graph

20 Commits

Author SHA1 Message Date
cui fliter cab90c84d1 sync: add available godoc link
Change-Id: I9bc5fd29b0eec8ceadcfee2116de5e7524ef92c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/539617
Auto-Submit: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Pratt <mpratt@google.com>
Run-TryBot: shuang cui <imcusg@gmail.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
2024-02-26 20:48:55 +00:00
Jes Cok 3b0d39c5da sync: update doc for Map.Clear
Change-Id: I9bcc5c82321cbc93f1c7aafd1dadf4f6b862ccbd
GitHub-Last-Rev: 818b95528f
GitHub-Pull-Request: golang/go#65429
Reviewed-on: https://go-review.googlesource.com/c/go/+/560396
Reviewed-by: Bryan Mills <bcmills@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2024-02-01 19:34:02 +00:00
Hiro 5b6cd3d0cb sync: add Map.Clear
Fixes #61696

Change-Id: I0a31afd3bc433fc84280d56f2798bda10da61eba
GitHub-Last-Rev: 17bedc864f
GitHub-Pull-Request: golang/go#61702
Reviewed-on: https://go-review.googlesource.com/c/go/+/515015
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: qiulaidongfeng <2645477756@qq.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
2024-02-01 15:34:22 +00:00
sivchari 10a66d6816 sync: use map[any]any instead of map[interface{}]interface{} in the godoc
It's shorter and clearer.

Change-Id: Ibfbe5a7f8d70fa884691ba9858a2c9b2122d9c50
Reviewed-on: https://go-review.googlesource.com/c/go/+/531475
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@google.com>
2024-01-08 17:02:01 +00:00
Mauri de Souza Meneguzzo 7015ed891c sync: prevent (*Map).Range from always escaping
After the change from CL 426074 the Range method on Map always
escape the read variable, leading to an allocation.

Since the compiler doesn't do live-range splitting for local variables we
need to use some hints to only escape in that particular branch.

Fixes #62404

Change-Id: I938a5e593647455fa827e3dd3ed8ea22c7365df1
GitHub-Last-Rev: fcbedb467c
GitHub-Pull-Request: golang/go#62408
Reviewed-on: https://go-review.googlesource.com/c/go/+/524976
Auto-Submit: Bryan Mills <bcmills@google.com>
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Run-TryBot: Bryan Mills <bcmills@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
2023-09-01 22:41:39 +00:00
Changkun Ou f07910bd57 sync: document memory model for Swap/CompareAnd{Swap,Delete} in Map
CL 381316 documented the memory model of Map's APIs. However, the newly
introduced Swap, CompareAndSwap, and CompareAndDelete are missing from
this documentation as CL 399094 did not add this info.

This CL specifies the defined read/write operations of the new Map APIs.

For #51972

Change-Id: I519a04040a0b429a3f978823a183cd62e42c90ae
Reviewed-on: https://go-review.googlesource.com/c/go/+/459715
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Run-TryBot: Changkun Ou <mail@changkun.de>
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
2023-01-20 19:38:29 +00:00
Changkun Ou 395323c4d0 sync: add new Map method Swap, CompareAndSwap, CompareAndDelete
name                                                   time/op
SwapCollision/*sync_test.DeepCopyMap-8                  235ns ± 0%
SwapCollision/*sync_test.RWMutexMap-8                   145ns ± 0%
SwapCollision/*sync.Map-8                               153ns ± 0%
SwapMostlyHits/*sync_test.DeepCopyMap-8                48.2µs ± 0%
SwapMostlyHits/*sync_test.RWMutexMap-8                  190ns ± 0%
SwapMostlyHits/*sync.Map-8                             28.3ns ± 0%
SwapMostlyMisses/*sync_test.DeepCopyMap-8               681ns ± 0%
SwapMostlyMisses/*sync_test.RWMutexMap-8                336ns ± 0%
SwapMostlyMisses/*sync.Map-8                            523ns ± 0%
CompareAndSwapCollision/*sync_test.DeepCopyMap-8       3.99ns ± 0%
CompareAndSwapCollision/*sync_test.RWMutexMap-8         151ns ± 0%
CompareAndSwapCollision/*sync.Map-8                    21.6ns ± 0%
CompareAndSwapNoExistingKey/*sync_test.DeepCopyMap-8   3.95ns ± 0%
CompareAndSwapNoExistingKey/*sync_test.RWMutexMap-8     126ns ± 0%
CompareAndSwapNoExistingKey/*sync.Map-8                6.11ns ± 0%
CompareAndSwapValueNotEqual/*sync_test.DeepCopyMap-8   2.15ns ± 0%
CompareAndSwapValueNotEqual/*sync_test.RWMutexMap-8     132ns ± 0%
CompareAndSwapValueNotEqual/*sync.Map-8                5.32ns ± 0%
CompareAndSwapMostlyHits/*sync_test.RWMutexMap-8        219ns ± 0%
CompareAndSwapMostlyHits/*sync.Map-8                   27.1ns ± 0%
CompareAndSwapMostlyMisses/*sync_test.DeepCopyMap-8    13.0ns ± 0%
CompareAndSwapMostlyMisses/*sync_test.RWMutexMap-8      147ns ± 0%
CompareAndSwapMostlyMisses/*sync.Map-8                 19.6ns ± 0%
CompareAndDeleteCollision/*sync_test.DeepCopyMap-8     2.23ns ± 0%
CompareAndDeleteCollision/*sync_test.RWMutexMap-8       131ns ± 0%
CompareAndDeleteCollision/*sync.Map-8                  16.2ns ± 0%
CompareAndDeleteMostlyHits/*sync_test.RWMutexMap-8      367ns ± 0%
CompareAndDeleteMostlyHits/*sync.Map-8                 33.1ns ± 0%
CompareAndDeleteMostlyMisses/*sync_test.DeepCopyMap-8  8.75ns ± 0%
CompareAndDeleteMostlyMisses/*sync_test.RWMutexMap-8    134ns ± 0%
CompareAndDeleteMostlyMisses/*sync.Map-8               10.9ns ± 0%

name                                                   alloc/op
SwapCollision/*sync_test.DeepCopyMap-8                   336B ± 0%
SwapCollision/*sync_test.RWMutexMap-8                   0.00B
SwapCollision/*sync.Map-8                               16.0B ± 0%
SwapMostlyHits/*sync_test.DeepCopyMap-8                82.1kB ± 0%
SwapMostlyHits/*sync_test.RWMutexMap-8                  12.0B ± 0%
SwapMostlyHits/*sync.Map-8                              28.0B ± 0%
SwapMostlyMisses/*sync_test.DeepCopyMap-8                713B ± 0%
SwapMostlyMisses/*sync_test.RWMutexMap-8                23.0B ± 0%
SwapMostlyMisses/*sync.Map-8                             129B ± 0%
CompareAndSwapCollision/*sync_test.DeepCopyMap-8        0.00B
CompareAndSwapCollision/*sync_test.RWMutexMap-8         0.00B
CompareAndSwapCollision/*sync.Map-8                     3.00B ± 0%
CompareAndSwapNoExistingKey/*sync_test.DeepCopyMap-8    8.00B ± 0%
CompareAndSwapNoExistingKey/*sync_test.RWMutexMap-8     8.00B ± 0%
CompareAndSwapNoExistingKey/*sync.Map-8                 8.00B ± 0%
CompareAndSwapValueNotEqual/*sync_test.DeepCopyMap-8    0.00B
CompareAndSwapValueNotEqual/*sync_test.RWMutexMap-8     0.00B
CompareAndSwapValueNotEqual/*sync.Map-8                 0.00B
CompareAndSwapMostlyHits/*sync_test.RWMutexMap-8        18.0B ± 0%
CompareAndSwapMostlyHits/*sync.Map-8                    33.0B ± 0%
CompareAndSwapMostlyMisses/*sync_test.DeepCopyMap-8     24.0B ± 0%
CompareAndSwapMostlyMisses/*sync_test.RWMutexMap-8      23.0B ± 0%
CompareAndSwapMostlyMisses/*sync.Map-8                  23.0B ± 0%
CompareAndDeleteCollision/*sync_test.DeepCopyMap-8      0.00B
CompareAndDeleteCollision/*sync_test.RWMutexMap-8       0.00B
CompareAndDeleteCollision/*sync.Map-8                   0.00B
CompareAndDeleteMostlyHits/*sync_test.RWMutexMap-8      23.0B ± 0%
CompareAndDeleteMostlyHits/*sync.Map-8                  39.0B ± 0%
CompareAndDeleteMostlyMisses/*sync_test.DeepCopyMap-8   16.0B ± 0%
CompareAndDeleteMostlyMisses/*sync_test.RWMutexMap-8    15.0B ± 0%
CompareAndDeleteMostlyMisses/*sync.Map-8                15.0B ± 0%

name                                                   allocs/op
SwapCollision/*sync_test.DeepCopyMap-8                   2.00 ± 0%
SwapCollision/*sync_test.RWMutexMap-8                    0.00
SwapCollision/*sync.Map-8                                1.00 ± 0%
SwapMostlyHits/*sync_test.DeepCopyMap-8                  4.00 ± 0%
SwapMostlyHits/*sync_test.RWMutexMap-8                   1.00 ± 0%
SwapMostlyHits/*sync.Map-8                               2.00 ± 0%
SwapMostlyMisses/*sync_test.DeepCopyMap-8                6.00 ± 0%
SwapMostlyMisses/*sync_test.RWMutexMap-8                 2.00 ± 0%
SwapMostlyMisses/*sync.Map-8                             6.00 ± 0%
CompareAndSwapCollision/*sync_test.DeepCopyMap-8         0.00
CompareAndSwapCollision/*sync_test.RWMutexMap-8          0.00
CompareAndSwapCollision/*sync.Map-8                      0.00
CompareAndSwapNoExistingKey/*sync_test.DeepCopyMap-8     1.00 ± 0%
CompareAndSwapNoExistingKey/*sync_test.RWMutexMap-8      0.00
CompareAndSwapNoExistingKey/*sync.Map-8                  1.00 ± 0%
CompareAndSwapValueNotEqual/*sync_test.DeepCopyMap-8     0.00
CompareAndSwapValueNotEqual/*sync_test.RWMutexMap-8      0.00
CompareAndSwapValueNotEqual/*sync.Map-8                  0.00
CompareAndSwapMostlyHits/*sync_test.RWMutexMap-8         2.00 ± 0%
CompareAndSwapMostlyHits/*sync.Map-8                     3.00 ± 0%
CompareAndSwapMostlyMisses/*sync_test.DeepCopyMap-8      2.00 ± 0%
CompareAndSwapMostlyMisses/*sync_test.RWMutexMap-8       2.00 ± 0%
CompareAndSwapMostlyMisses/*sync.Map-8                   2.00 ± 0%
CompareAndDeleteCollision/*sync_test.DeepCopyMap-8       0.00
CompareAndDeleteCollision/*sync_test.RWMutexMap-8        0.00
CompareAndDeleteCollision/*sync.Map-8                    0.00
CompareAndDeleteMostlyHits/*sync_test.RWMutexMap-8       2.00 ± 0%
CompareAndDeleteMostlyHits/*sync.Map-8                   3.00 ± 0%
CompareAndDeleteMostlyMisses/*sync_test.DeepCopyMap-8    2.00 ± 0%
CompareAndDeleteMostlyMisses/*sync_test.RWMutexMap-8     1.00 ± 0%
CompareAndDeleteMostlyMisses/*sync.Map-8                 1.00 ± 0%

Fixes #51972

Change-Id: I469e71033592997832c3e8ebdad1b8950a70c99c
Reviewed-on: https://go-review.googlesource.com/c/go/+/399094
Run-TryBot: Changkun Ou <mail@changkun.de>
Reviewed-by: Joedian Reid <joedian@golang.org>
Auto-Submit: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
2022-11-15 17:35:42 +00:00
Changkun Ou 7366b199c5 sync: use atomic.Pointer for entry
Change-Id: Ie3b4bfe483d7ef43da29ea1dd73d423dac36cf39
Reviewed-on: https://go-review.googlesource.com/c/go/+/432055
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Changkun Ou <mail@changkun.de>
2022-10-31 20:12:59 +00:00
Joe Tsai b0144b3843 sync: switch Map to use atomic.Pointer
There was no noticeable change in performance.

Change-Id: I9c57bf836c8b6066e0620afb3d536ce99e4b9d87
Reviewed-on: https://go-review.googlesource.com/c/go/+/426074
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
TryBot-Result: Gopher Robot <gobot@golang.org>
2022-08-29 20:09:02 +00:00
Russ Cox a71ca3dfbd runtime, sync, sync/atomic: document happens-before guarantees
A few of these are copied from the memory model doc.
Many are entirely new, following discussion on #47141.
See https://research.swtch.com/gomm for background.

The rule we are establishing is that each type that is meant
to help synchronize a Go program should document its
happens-before guarantees.

For #50859.

Change-Id: I947c40639b263abe67499fa74f68711a97873a39
Reviewed-on: https://go-review.googlesource.com/c/go/+/381316
Auto-Submit: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Roland Shoemaker <roland@golang.org>
2022-06-06 20:48:03 +00:00
Russ Cox 2580d0e08d all: gofmt -w -r 'interface{} -> any' src
And then revert the bootstrap cmd directories and certain testdata.
And adjust tests as needed.

Not reverting the changes in std that are bootstrapped,
because some of those changes would appear in API docs,
and we want to use any consistently.
Instead, rewrite 'any' to 'interface{}' in cmd/dist for those directories
when preparing the bootstrap copy.

A few files changed as a result of running gofmt -w
not because of interface{} -> any but because they
hadn't been updated for the new //go:build lines.

Fixes #49884.

Change-Id: Ie8045cba995f65bd79c694ec77a1b3d1fe01bb09
Reviewed-on: https://go-review.googlesource.com/c/go/+/368254
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
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2021-12-13 18:45:54 +00:00
Changkun Ou d5a5a13ad9 sync: clarify the validity to call Map methods inside Range
This change clarifies that calling all Map methods inside the callback
of Range is allowed. For further assurance, a nested range call test
is also added.

Fixes #46399

Change-Id: I0a766a5c1470e6b573ec35df1ccd62b2e46f1561
Reviewed-on: https://go-review.googlesource.com/c/go/+/337389
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Ian Lance Taylor <iant@golang.org>
2021-11-11 04:41:56 +00:00
panchenglong01 1749f3915e sync: update misleading comment in map.go about entry type
As discussed in: https://github.com/golang/go/issues/45429,  about entry
type comments, it is possible for p == nil when m.dirty != nil, so
update the commemt about it.

Fixes #45429

Change-Id: I7ef96ee5b6948df9ac736481d177a59ab66d7d4d
GitHub-Last-Rev: 202c598a0a
GitHub-Pull-Request: golang/go#45443
Reviewed-on: https://go-review.googlesource.com/c/go/+/308292
Reviewed-by: Changkun Ou <euryugasaki@gmail.com>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Trust: Robert Findley <rfindley@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
2021-04-08 14:08:29 +00:00
Changkun Ou 94953d3e59 sync: delete dirty keys inside Map.LoadAndDelete
Fixes #40999

Change-Id: Ie32427e5cb5ed512b976b554850f50be156ce9f2
Reviewed-on: https://go-review.googlesource.com/c/go/+/250197
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2020-08-24 20:05:41 +00:00
Changkun Ou 2e8dbae85c sync: add new Map method LoadAndDelete
This CL implements a LoadAndDelete method in sync.Map. Benchmark:

name                                              time/op
LoadAndDeleteBalanced/*sync_test.RWMutexMap-12    98.8ns ± 1%
LoadAndDeleteBalanced/*sync.Map-12                10.3ns ±11%
LoadAndDeleteUnique/*sync_test.RWMutexMap-12      99.2ns ± 2%
LoadAndDeleteUnique/*sync.Map-12                  6.63ns ±10%
LoadAndDeleteCollision/*sync_test.DeepCopyMap-12   140ns ± 0%
LoadAndDeleteCollision/*sync_test.RWMutexMap-12   75.2ns ± 2%
LoadAndDeleteCollision/*sync.Map-12               5.21ns ± 5%

In addition, Delete is bounded and more efficient if many collisions:

DeleteCollision/*sync_test.DeepCopyMap-12   120ns ± 2%   125ns ± 1%   +3.80%  (p=0.000 n=10+9)
DeleteCollision/*sync_test.RWMutexMap-12   73.5ns ± 3%  79.5ns ± 1%   +8.03%  (p=0.000 n=10+9)
DeleteCollision/*sync.Map-12               97.8ns ± 3%   5.9ns ± 4%  -94.00%  (p=0.000 n=10+10)

Fixes #33762

Change-Id: Ic8469a7861d27ab0edeface0078aad8af9b26c2f
Reviewed-on: https://go-review.googlesource.com/c/go/+/205899
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2020-02-25 14:31:55 +00:00
Ian Lance Taylor 756c352963 sync: simplify (*entry).tryStore
The only change to the go build -gcflags=-m=2 output was to remove
these two lines:

sync/map.go:178:26: &e.p escapes to heap
sync/map.go:178:26: 	from &e.p (passed to call[argument escapes]) at sync/map.go:178:25

Benchstat report for sync.Map benchmarks:

name                                            old time/op  new time/op  delta
LoadMostlyHits/*sync_test.DeepCopyMap-12        10.6ns ±11%  10.2ns ± 3%    ~     (p=0.299 n=10+8)
LoadMostlyHits/*sync_test.RWMutexMap-12         54.6ns ± 3%  54.6ns ± 2%    ~     (p=0.782 n=10+10)
LoadMostlyHits/*sync.Map-12                     10.1ns ± 1%  10.1ns ± 1%    ~     (p=1.127 n=10+8)
LoadMostlyMisses/*sync_test.DeepCopyMap-12      8.65ns ± 1%  8.77ns ± 5%  +1.39%  (p=0.017 n=9+10)
LoadMostlyMisses/*sync_test.RWMutexMap-12       53.6ns ± 2%  53.8ns ± 2%    ~     (p=0.408 n=10+9)
LoadMostlyMisses/*sync.Map-12                   7.37ns ± 1%  7.46ns ± 1%  +1.19%  (p=0.000 n=9+10)
LoadOrStoreBalanced/*sync_test.RWMutexMap-12     895ns ± 4%   906ns ± 3%    ~     (p=0.203 n=9+10)
LoadOrStoreBalanced/*sync.Map-12                 872ns ±10%   804ns ±12%  -7.75%  (p=0.014 n=10+10)
LoadOrStoreUnique/*sync_test.RWMutexMap-12      1.29µs ± 2%  1.28µs ± 1%    ~     (p=0.586 n=10+9)
LoadOrStoreUnique/*sync.Map-12                  1.30µs ± 7%  1.40µs ± 2%  +6.95%  (p=0.000 n=9+10)
LoadOrStoreCollision/*sync_test.DeepCopyMap-12  6.98ns ± 1%  6.91ns ± 1%  -1.10%  (p=0.000 n=10+10)
LoadOrStoreCollision/*sync_test.RWMutexMap-12    371ns ± 1%   372ns ± 2%    ~     (p=0.679 n=9+9)
LoadOrStoreCollision/*sync.Map-12               5.49ns ± 1%  5.49ns ± 1%    ~     (p=0.732 n=9+10)
Range/*sync_test.DeepCopyMap-12                 2.49µs ± 1%  2.50µs ± 0%    ~     (p=0.148 n=10+10)
Range/*sync_test.RWMutexMap-12                  54.7µs ± 1%  54.6µs ± 3%    ~     (p=0.549 n=9+10)
Range/*sync.Map-12                              2.74µs ± 1%  2.76µs ± 1%  +0.68%  (p=0.011 n=10+8)
AdversarialAlloc/*sync_test.DeepCopyMap-12      2.52µs ± 5%  2.54µs ± 7%    ~     (p=0.225 n=10+10)
AdversarialAlloc/*sync_test.RWMutexMap-12        108ns ± 1%   107ns ± 1%    ~     (p=0.101 n=10+9)
AdversarialAlloc/*sync.Map-12                    712ns ± 2%   714ns ± 3%    ~     (p=0.984 n=8+10)
AdversarialDelete/*sync_test.DeepCopyMap-12      581ns ± 3%   578ns ± 3%    ~     (p=0.781 n=9+9)
AdversarialDelete/*sync_test.RWMutexMap-12       126ns ± 2%   126ns ± 1%    ~     (p=0.883 n=10+10)
AdversarialDelete/*sync.Map-12                   155ns ± 8%   158ns ± 2%    ~     (p=0.158 n=10+9)

Change-Id: I1ed8e3109baca03087d0fad3df769fc7e38f6dbb
Reviewed-on: https://go-review.googlesource.com/137441
Reviewed-by: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-09-27 21:44:20 +00:00
Russ Cox 3f150934e2 sync: document when and when not to use Map
Fixes #21587.

Change-Id: I47eb181d65da67a3b530c7f8acac9c0c619ea474
Reviewed-on: https://go-review.googlesource.com/83796
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-01-04 20:13:20 +00:00
Brad Fitzpatrick 5f7a03e148 sync: delete a sentence from the Map docs
From Josh's comments on https://golang.org/cl/50310

Once I removed the "from the Go standard library" bit, the beginning
wasn't worth keeping. It also wasn't clear whether what it meant by
"cache contention". Processor caches, or user-level caches built with
sync.Map? It didn't seem worth clarifying and didn't convey any useful
information, so deleted.

Change-Id: Id1d76105a3081d0855f6a64540700932bb83d98e
Reviewed-on: https://go-review.googlesource.com/50632
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
2017-07-21 22:00:47 +00:00
Michael Stapelberg ace7ce1025 sync: update Map documentation with usage rule of thumb
As per bcmills’s lightning talk at GopherCon 2017:
https://github.com/gophercon/2017-talks/tree/master/lightningtalks/BryanCMills-AnOverviewOfSyncMap

Change-Id: I12dd0daa608af175d110298780f32c6dc5e1e0a0
Reviewed-on: https://go-review.googlesource.com/50310
Reviewed-by: Bryan Mills <bcmills@google.com>
2017-07-21 16:02:43 +00:00
Bryan C. Mills 959025c0ac sync: import Map from x/sync/syncmap
This is a direct port of the version from
commit a60ad46e0ed33d02e09bda439efaf9c9727dbc6c
(https://go-review.googlesource.com/c/37342/).

updates #17973
updates #18177

Change-Id: I63fa5ef6951b1edd39f84927d1181a4df9b15385
Reviewed-on: https://go-review.googlesource.com/36617
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-04-26 18:05:06 +00:00