From 2e8dbae85ce88d02f651e53338984288057f14cb Mon Sep 17 00:00:00 2001 From: Changkun Ou Date: Fri, 8 Nov 2019 11:23:58 +0100 Subject: sync: add new Map method LoadAndDelete MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Run-TryBot: Bryan C. Mills TryBot-Result: Gobot Gobot --- src/sync/map_reference_test.go | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'src/sync/map_reference_test.go') diff --git a/src/sync/map_reference_test.go b/src/sync/map_reference_test.go index 9f27b07c32..d105a24e92 100644 --- a/src/sync/map_reference_test.go +++ b/src/sync/map_reference_test.go @@ -16,6 +16,7 @@ type mapInterface interface { Load(interface{}) (interface{}, bool) Store(key, value interface{}) LoadOrStore(key, value interface{}) (actual interface{}, loaded bool) + LoadAndDelete(key interface{}) (value interface{}, loaded bool) Delete(interface{}) Range(func(key, value interface{}) (shouldContinue bool)) } @@ -56,6 +57,18 @@ func (m *RWMutexMap) LoadOrStore(key, value interface{}) (actual interface{}, lo return actual, loaded } +func (m *RWMutexMap) LoadAndDelete(key interface{}) (value interface{}, loaded bool) { + m.mu.Lock() + value, loaded = m.dirty[key] + if !loaded { + m.mu.Unlock() + return nil, false + } + delete(m.dirty, key) + m.mu.Unlock() + return value, loaded +} + func (m *RWMutexMap) Delete(key interface{}) { m.mu.Lock() delete(m.dirty, key) @@ -124,6 +137,16 @@ func (m *DeepCopyMap) LoadOrStore(key, value interface{}) (actual interface{}, l return actual, loaded } +func (m *DeepCopyMap) LoadAndDelete(key interface{}) (value interface{}, loaded bool) { + m.mu.Lock() + dirty := m.dirty() + value, loaded = dirty[key] + delete(dirty, key) + m.clean.Store(dirty) + m.mu.Unlock() + return +} + func (m *DeepCopyMap) Delete(key interface{}) { m.mu.Lock() dirty := m.dirty() -- cgit v1.3