feat(blockstore) write cache
vendors hashicorp/golang-lru dependency. (Mozilla Public License, version 2.0) License: MIT Signed-off-by: Brian Tiger Chow <brian@perfmode.com>
Brian Tiger Chow committed
Nov 30, 2014 at 21:25 UTC
c40fe2af17b8856587f0e7d9a8d2fe42ddcc277a
8 files changed
+729
Godeps/Godeps.json
+4
@@ -89,6 +89,10 @@
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"ImportPath": "github.com/inconshreveable/go-update",
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"Rev": "221d034a558b4c21b0624b2a450c076913854a57"
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},
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+ {
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+ "ImportPath": "github.com/hashicorp/golang-lru",
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+ "Rev": "253b2dc1ca8bae42c3b5b6e53dd2eab1a7551116"
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+ },
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{
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"ImportPath": "github.com/jbenet/go-base58",
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"Rev": "568a28d73fd97651d3442392036a658b6976eed5"
Godeps/_workspace/src/github.com/hashicorp/golang-lru/.gitignore
new
+23
@@ -0,0 +1,23 @@
1
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
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+*.o
3
+*.a
4
+*.so
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+
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+# Folders
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+_obj
8
+_test
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+
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+# Architecture specific extensions/prefixes
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+*.[568vq]
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+[568vq].out
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+
14
+*.cgo1.go
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+*.cgo2.c
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+_cgo_defun.c
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+_cgo_gotypes.go
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+_cgo_export.*
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+
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+_testmain.go
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+
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+*.exe
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+*.test
Godeps/_workspace/src/github.com/hashicorp/golang-lru/LICENSE
new
+362
@@ -0,0 +1,362 @@
1
+Mozilla Public License, version 2.0
2
+
3
+1. Definitions
4
+
5
+1.1. "Contributor"
6
+
7
+ means each individual or legal entity that creates, contributes to the
8
+ creation of, or owns Covered Software.
9
+
10
+1.2. "Contributor Version"
11
+
12
+ means the combination of the Contributions of others (if any) used by a
13
+ Contributor and that particular Contributor's Contribution.
14
+
15
+1.3. "Contribution"
16
+
17
+ means Covered Software of a particular Contributor.
18
+
19
+1.4. "Covered Software"
20
+
21
+ means Source Code Form to which the initial Contributor has attached the
22
+ notice in Exhibit A, the Executable Form of such Source Code Form, and
23
+ Modifications of such Source Code Form, in each case including portions
24
+ thereof.
25
+
26
+1.5. "Incompatible With Secondary Licenses"
27
+ means
28
+
29
+ a. that the initial Contributor has attached the notice described in
30
+ Exhibit B to the Covered Software; or
31
+
32
+ b. that the Covered Software was made available under the terms of
33
+ version 1.1 or earlier of the License, but not also under the terms of
34
+ a Secondary License.
35
+
36
+1.6. "Executable Form"
37
+
38
+ means any form of the work other than Source Code Form.
39
+
40
+1.7. "Larger Work"
41
+
42
+ means a work that combines Covered Software with other material, in a
43
+ separate file or files, that is not Covered Software.
44
+
45
+1.8. "License"
46
+
47
+ means this document.
48
+
49
+1.9. "Licensable"
50
+
51
+ means having the right to grant, to the maximum extent possible, whether
52
+ at the time of the initial grant or subsequently, any and all of the
53
+ rights conveyed by this License.
54
+
55
+1.10. "Modifications"
56
+
57
+ means any of the following:
58
+
59
+ a. any file in Source Code Form that results from an addition to,
60
+ deletion from, or modification of the contents of Covered Software; or
61
+
62
+ b. any new file in Source Code Form that contains any Covered Software.
63
+
64
+1.11. "Patent Claims" of a Contributor
65
+
66
+ means any patent claim(s), including without limitation, method,
67
+ process, and apparatus claims, in any patent Licensable by such
68
+ Contributor that would be infringed, but for the grant of the License,
69
+ by the making, using, selling, offering for sale, having made, import,
70
+ or transfer of either its Contributions or its Contributor Version.
71
+
72
+1.12. "Secondary License"
73
+
74
+ means either the GNU General Public License, Version 2.0, the GNU Lesser
75
+ General Public License, Version 2.1, the GNU Affero General Public
76
+ License, Version 3.0, or any later versions of those licenses.
77
+
78
+1.13. "Source Code Form"
79
+
80
+ means the form of the work preferred for making modifications.
81
+
82
+1.14. "You" (or "Your")
83
+
84
+ means an individual or a legal entity exercising rights under this
85
+ License. For legal entities, "You" includes any entity that controls, is
86
+ controlled by, or is under common control with You. For purposes of this
87
+ definition, "control" means (a) the power, direct or indirect, to cause
88
+ the direction or management of such entity, whether by contract or
89
+ otherwise, or (b) ownership of more than fifty percent (50%) of the
90
+ outstanding shares or beneficial ownership of such entity.
91
+
92
+
93
+2. License Grants and Conditions
94
+
95
+2.1. Grants
96
+
97
+ Each Contributor hereby grants You a world-wide, royalty-free,
98
+ non-exclusive license:
99
+
100
+ a. under intellectual property rights (other than patent or trademark)
101
+ Licensable by such Contributor to use, reproduce, make available,
102
+ modify, display, perform, distribute, and otherwise exploit its
103
+ Contributions, either on an unmodified basis, with Modifications, or
104
+ as part of a Larger Work; and
105
+
106
+ b. under Patent Claims of such Contributor to make, use, sell, offer for
107
+ sale, have made, import, and otherwise transfer either its
108
+ Contributions or its Contributor Version.
109
+
110
+2.2. Effective Date
111
+
112
+ The licenses granted in Section 2.1 with respect to any Contribution
113
+ become effective for each Contribution on the date the Contributor first
114
+ distributes such Contribution.
115
+
116
+2.3. Limitations on Grant Scope
117
+
118
+ The licenses granted in this Section 2 are the only rights granted under
119
+ this License. No additional rights or licenses will be implied from the
120
+ distribution or licensing of Covered Software under this License.
121
+ Notwithstanding Section 2.1(b) above, no patent license is granted by a
122
+ Contributor:
123
+
124
+ a. for any code that a Contributor has removed from Covered Software; or
125
+
126
+ b. for infringements caused by: (i) Your and any other third party's
127
+ modifications of Covered Software, or (ii) the combination of its
128
+ Contributions with other software (except as part of its Contributor
129
+ Version); or
130
+
131
+ c. under Patent Claims infringed by Covered Software in the absence of
132
+ its Contributions.
133
+
134
+ This License does not grant any rights in the trademarks, service marks,
135
+ or logos of any Contributor (except as may be necessary to comply with
136
+ the notice requirements in Section 3.4).
137
+
138
+2.4. Subsequent Licenses
139
+
140
+ No Contributor makes additional grants as a result of Your choice to
141
+ distribute the Covered Software under a subsequent version of this
142
+ License (see Section 10.2) or under the terms of a Secondary License (if
143
+ permitted under the terms of Section 3.3).
144
+
145
+2.5. Representation
146
+
147
+ Each Contributor represents that the Contributor believes its
148
+ Contributions are its original creation(s) or it has sufficient rights to
149
+ grant the rights to its Contributions conveyed by this License.
150
+
151
+2.6. Fair Use
152
+
153
+ This License is not intended to limit any rights You have under
154
+ applicable copyright doctrines of fair use, fair dealing, or other
155
+ equivalents.
156
+
157
+2.7. Conditions
158
+
159
+ Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted in
160
+ Section 2.1.
161
+
162
+
163
+3. Responsibilities
164
+
165
+3.1. Distribution of Source Form
166
+
167
+ All distribution of Covered Software in Source Code Form, including any
168
+ Modifications that You create or to which You contribute, must be under
169
+ the terms of this License. You must inform recipients that the Source
170
+ Code Form of the Covered Software is governed by the terms of this
171
+ License, and how they can obtain a copy of this License. You may not
172
+ attempt to alter or restrict the recipients' rights in the Source Code
173
+ Form.
174
+
175
+3.2. Distribution of Executable Form
176
+
177
+ If You distribute Covered Software in Executable Form then:
178
+
179
+ a. such Covered Software must also be made available in Source Code Form,
180
+ as described in Section 3.1, and You must inform recipients of the
181
+ Executable Form how they can obtain a copy of such Source Code Form by
182
+ reasonable means in a timely manner, at a charge no more than the cost
183
+ of distribution to the recipient; and
184
+
185
+ b. You may distribute such Executable Form under the terms of this
186
+ License, or sublicense it under different terms, provided that the
187
+ license for the Executable Form does not attempt to limit or alter the
188
+ recipients' rights in the Source Code Form under this License.
189
+
190
+3.3. Distribution of a Larger Work
191
+
192
+ You may create and distribute a Larger Work under terms of Your choice,
193
+ provided that You also comply with the requirements of this License for
194
+ the Covered Software. If the Larger Work is a combination of Covered
195
+ Software with a work governed by one or more Secondary Licenses, and the
196
+ Covered Software is not Incompatible With Secondary Licenses, this
197
+ License permits You to additionally distribute such Covered Software
198
+ under the terms of such Secondary License(s), so that the recipient of
199
+ the Larger Work may, at their option, further distribute the Covered
200
+ Software under the terms of either this License or such Secondary
201
+ License(s).
202
+
203
+3.4. Notices
204
+
205
+ You may not remove or alter the substance of any license notices
206
+ (including copyright notices, patent notices, disclaimers of warranty, or
207
+ limitations of liability) contained within the Source Code Form of the
208
+ Covered Software, except that You may alter any license notices to the
209
+ extent required to remedy known factual inaccuracies.
210
+
211
+3.5. Application of Additional Terms
212
+
213
+ You may choose to offer, and to charge a fee for, warranty, support,
214
+ indemnity or liability obligations to one or more recipients of Covered
215
+ Software. However, You may do so only on Your own behalf, and not on
216
+ behalf of any Contributor. You must make it absolutely clear that any
217
+ such warranty, support, indemnity, or liability obligation is offered by
218
+ You alone, and You hereby agree to indemnify every Contributor for any
219
+ liability incurred by such Contributor as a result of warranty, support,
220
+ indemnity or liability terms You offer. You may include additional
221
+ disclaimers of warranty and limitations of liability specific to any
222
+ jurisdiction.
223
+
224
+4. Inability to Comply Due to Statute or Regulation
225
+
226
+ If it is impossible for You to comply with any of the terms of this License
227
+ with respect to some or all of the Covered Software due to statute,
228
+ judicial order, or regulation then You must: (a) comply with the terms of
229
+ this License to the maximum extent possible; and (b) describe the
230
+ limitations and the code they affect. Such description must be placed in a
231
+ text file included with all distributions of the Covered Software under
232
+ this License. Except to the extent prohibited by statute or regulation,
233
+ such description must be sufficiently detailed for a recipient of ordinary
234
+ skill to be able to understand it.
235
+
236
+5. Termination
237
+
238
+5.1. The rights granted under this License will terminate automatically if You
239
+ fail to comply with any of its terms. However, if You become compliant,
240
+ then the rights granted under this License from a particular Contributor
241
+ are reinstated (a) provisionally, unless and until such Contributor
242
+ explicitly and finally terminates Your grants, and (b) on an ongoing
243
+ basis, if such Contributor fails to notify You of the non-compliance by
244
+ some reasonable means prior to 60 days after You have come back into
245
+ compliance. Moreover, Your grants from a particular Contributor are
246
+ reinstated on an ongoing basis if such Contributor notifies You of the
247
+ non-compliance by some reasonable means, this is the first time You have
248
+ received notice of non-compliance with this License from such
249
+ Contributor, and You become compliant prior to 30 days after Your receipt
250
+ of the notice.
251
+
252
+5.2. If You initiate litigation against any entity by asserting a patent
253
+ infringement claim (excluding declaratory judgment actions,
254
+ counter-claims, and cross-claims) alleging that a Contributor Version
255
+ directly or indirectly infringes any patent, then the rights granted to
256
+ You by any and all Contributors for the Covered Software under Section
257
+ 2.1 of this License shall terminate.
258
+
259
+5.3. In the event of termination under Sections 5.1 or 5.2 above, all end user
260
+ license agreements (excluding distributors and resellers) which have been
261
+ validly granted by You or Your distributors under this License prior to
262
+ termination shall survive termination.
263
+
264
+6. Disclaimer of Warranty
265
+
266
+ Covered Software is provided under this License on an "as is" basis,
267
+ without warranty of any kind, either expressed, implied, or statutory,
268
+ including, without limitation, warranties that the Covered Software is free
269
+ of defects, merchantable, fit for a particular purpose or non-infringing.
270
+ The entire risk as to the quality and performance of the Covered Software
271
+ is with You. Should any Covered Software prove defective in any respect,
272
+ You (not any Contributor) assume the cost of any necessary servicing,
273
+ repair, or correction. This disclaimer of warranty constitutes an essential
274
+ part of this License. No use of any Covered Software is authorized under
275
+ this License except under this disclaimer.
276
+
277
+7. Limitation of Liability
278
+
279
+ Under no circumstances and under no legal theory, whether tort (including
280
+ negligence), contract, or otherwise, shall any Contributor, or anyone who
281
+ distributes Covered Software as permitted above, be liable to You for any
282
+ direct, indirect, special, incidental, or consequential damages of any
283
+ character including, without limitation, damages for lost profits, loss of
284
+ goodwill, work stoppage, computer failure or malfunction, or any and all
285
+ other commercial damages or losses, even if such party shall have been
286
+ informed of the possibility of such damages. This limitation of liability
287
+ shall not apply to liability for death or personal injury resulting from
288
+ such party's negligence to the extent applicable law prohibits such
289
+ limitation. Some jurisdictions do not allow the exclusion or limitation of
290
+ incidental or consequential damages, so this exclusion and limitation may
291
+ not apply to You.
292
+
293
+8. Litigation
294
+
295
+ Any litigation relating to this License may be brought only in the courts
296
+ of a jurisdiction where the defendant maintains its principal place of
297
+ business and such litigation shall be governed by laws of that
298
+ jurisdiction, without reference to its conflict-of-law provisions. Nothing
299
+ in this Section shall prevent a party's ability to bring cross-claims or
300
+ counter-claims.
301
+
302
+9. Miscellaneous
303
+
304
+ This License represents the complete agreement concerning the subject
305
+ matter hereof. If any provision of this License is held to be
306
+ unenforceable, such provision shall be reformed only to the extent
307
+ necessary to make it enforceable. Any law or regulation which provides that
308
+ the language of a contract shall be construed against the drafter shall not
309
+ be used to construe this License against a Contributor.
310
+
311
+
312
+10. Versions of the License
313
+
314
+10.1. New Versions
315
+
316
+ Mozilla Foundation is the license steward. Except as provided in Section
317
+ 10.3, no one other than the license steward has the right to modify or
318
+ publish new versions of this License. Each version will be given a
319
+ distinguishing version number.
320
+
321
+10.2. Effect of New Versions
322
+
323
+ You may distribute the Covered Software under the terms of the version
324
+ of the License under which You originally received the Covered Software,
325
+ or under the terms of any subsequent version published by the license
326
+ steward.
327
+
328
+10.3. Modified Versions
329
+
330
+ If you create software not governed by this License, and you want to
331
+ create a new license for such software, you may create and use a
332
+ modified version of this License if you rename the license and remove
333
+ any references to the name of the license steward (except to note that
334
+ such modified license differs from this License).
335
+
336
+10.4. Distributing Source Code Form that is Incompatible With Secondary
337
+ Licenses If You choose to distribute Source Code Form that is
338
+ Incompatible With Secondary Licenses under the terms of this version of
339
+ the License, the notice described in Exhibit B of this License must be
340
+ attached.
341
+
342
+Exhibit A - Source Code Form License Notice
343
+
344
+ This Source Code Form is subject to the
345
+ terms of the Mozilla Public License, v.
346
+ 2.0. If a copy of the MPL was not
347
+ distributed with this file, You can
348
+ obtain one at
349
+ http://mozilla.org/MPL/2.0/.
350
+
351
+If it is not possible or desirable to put the notice in a particular file,
352
+then You may include the notice in a location (such as a LICENSE file in a
353
+relevant directory) where a recipient would be likely to look for such a
354
+notice.
355
+
356
+You may add additional accurate notices of copyright ownership.
357
+
358
+Exhibit B - "Incompatible With Secondary Licenses" Notice
359
+
360
+ This Source Code Form is "Incompatible
361
+ With Secondary Licenses", as defined by
362
+ the Mozilla Public License, v. 2.0.
Godeps/_workspace/src/github.com/hashicorp/golang-lru/README.md
new
+25
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1
+golang-lru
2
+==========
3
+
4
+This provides the `lru` package which implements a fixed-size
5
+thread safe LRU cache. It is based on the cache in Groupcache.
6
+
7
+Documentation
8
+=============
9
+
10
+Full docs are available on [Godoc](http://godoc.org/github.com/hashicorp/golang-lru)
11
+
12
+Example
13
+=======
14
+
15
+Using the LRU is very simple:
16
+
17
+```go
18
+l, _ := New(128)
19
+for i := 0; i < 256; i++ {
20
+ l.Add(i, nil)
21
+}
22
+if l.Len() != 128 {
23
+ panic("bad len: %v", l.Len())
24
+}
25
+```
Godeps/_workspace/src/github.com/hashicorp/golang-lru/lru.go
new
+134
@@ -0,0 +1,134 @@
1
+// This package provides a simple LRU cache. It is based on the
2
+// LRU implementation in groupcache:
3
+// https://github.com/golang/groupcache/tree/master/lru
4
+package lru
5
+
6
+import (
7
+ "container/list"
8
+ "errors"
9
+ "sync"
10
+)
11
+
12
+// Cache is a thread-safe fixed size LRU cache.
13
+type Cache struct {
14
+ size int
15
+ evictList *list.List
16
+ items map[interface{}]*list.Element
17
+ lock sync.Mutex
18
+}
19
+
20
+// entry is used to hold a value in the evictList
21
+type entry struct {
22
+ key interface{}
23
+ value interface{}
24
+}
25
+
26
+// New creates an LRU of the given size
27
+func New(size int) (*Cache, error) {
28
+ if size <= 0 {
29
+ return nil, errors.New("Must provide a positive size")
30
+ }
31
+ c := &Cache{
32
+ size: size,
33
+ evictList: list.New(),
34
+ items: make(map[interface{}]*list.Element, size),
35
+ }
36
+ return c, nil
37
+}
38
+
39
+// Purge is used to completely clear the cache
40
+func (c *Cache) Purge() {
41
+ c.lock.Lock()
42
+ defer c.lock.Unlock()
43
+ c.evictList = list.New()
44
+ c.items = make(map[interface{}]*list.Element, c.size)
45
+}
46
+
47
+// Add adds a value to the cache.
48
+func (c *Cache) Add(key, value interface{}) {
49
+ c.lock.Lock()
50
+ defer c.lock.Unlock()
51
+
52
+ // Check for existing item
53
+ if ent, ok := c.items[key]; ok {
54
+ c.evictList.MoveToFront(ent)
55
+ ent.Value.(*entry).value = value
56
+ return
57
+ }
58
+
59
+ // Add new item
60
+ ent := &entry{key, value}
61
+ entry := c.evictList.PushFront(ent)
62
+ c.items[key] = entry
63
+
64
+ // Verify size not exceeded
65
+ if c.evictList.Len() > c.size {
66
+ c.removeOldest()
67
+ }
68
+}
69
+
70
+// Get looks up a key's value from the cache.
71
+func (c *Cache) Get(key interface{}) (value interface{}, ok bool) {
72
+ c.lock.Lock()
73
+ defer c.lock.Unlock()
74
+
75
+ if ent, ok := c.items[key]; ok {
76
+ c.evictList.MoveToFront(ent)
77
+ return ent.Value.(*entry).value, true
78
+ }
79
+ return
80
+}
81
+
82
+// Remove removes the provided key from the cache.
83
+func (c *Cache) Remove(key interface{}) {
84
+ c.lock.Lock()
85
+ defer c.lock.Unlock()
86
+
87
+ if ent, ok := c.items[key]; ok {
88
+ c.removeElement(ent)
89
+ }
90
+}
91
+
92
+// RemoveOldest removes the oldest item from the cache.
93
+func (c *Cache) RemoveOldest() {
94
+ c.lock.Lock()
95
+ defer c.lock.Unlock()
96
+ c.removeOldest()
97
+}
98
+
99
+// Keys returns a slice of the keys in the cache.
100
+func (c *Cache) Keys() []interface{} {
101
+ c.lock.Lock()
102
+ defer c.lock.Unlock()
103
+
104
+ keys := make([]interface{}, len(c.items))
105
+ i := 0
106
+ for k := range c.items {
107
+ keys[i] = k
108
+ i++
109
+ }
110
+
111
+ return keys
112
+}
113
+
114
+// removeOldest removes the oldest item from the cache.
115
+func (c *Cache) removeOldest() {
116
+ ent := c.evictList.Back()
117
+ if ent != nil {
118
+ c.removeElement(ent)
119
+ }
120
+}
121
+
122
+// removeElement is used to remove a given list element from the cache
123
+func (c *Cache) removeElement(e *list.Element) {
124
+ c.evictList.Remove(e)
125
+ kv := e.Value.(*entry)
126
+ delete(c.items, kv.key)
127
+}
128
+
129
+// Len returns the number of items in the cache.
130
+func (c *Cache) Len() int {
131
+ c.lock.Lock()
132
+ defer c.lock.Unlock()
133
+ return c.evictList.Len()
134
+}
Godeps/_workspace/src/github.com/hashicorp/golang-lru/lru_test.go
new
+48
@@ -0,0 +1,48 @@
1
+package lru
2
+
3
+import "testing"
4
+
5
+func TestLRU(t *testing.T) {
6
+ l, err := New(128)
7
+ if err != nil {
8
+ t.Fatalf("err: %v", err)
9
+ }
10
+ for i := 0; i < 256; i++ {
11
+ l.Add(i, i)
12
+ }
13
+ if l.Len() != 128 {
14
+ t.Fatalf("bad len: %v", l.Len())
15
+ }
16
+ for _, k := range l.Keys() {
17
+ if v, ok := l.Get(k); !ok || v != k {
18
+ t.Fatalf("bad key: %v", k)
19
+ }
20
+ }
21
+ for i := 0; i < 128; i++ {
22
+ _, ok := l.Get(i)
23
+ if ok {
24
+ t.Fatalf("should be evicted")
25
+ }
26
+ }
27
+ for i := 128; i < 256; i++ {
28
+ _, ok := l.Get(i)
29
+ if !ok {
30
+ t.Fatalf("should not be evicted")
31
+ }
32
+ }
33
+ for i := 128; i < 192; i++ {
34
+ l.Remove(i)
35
+ _, ok := l.Get(i)
36
+ if ok {
37
+ t.Fatalf("should be deleted")
38
+ }
39
+ }
40
+
41
+ l.Purge()
42
+ if l.Len() != 0 {
43
+ t.Fatalf("bad len: %v", l.Len())
44
+ }
45
+ if _, ok := l.Get(200); ok {
46
+ t.Fatalf("should contain nothing")
47
+ }
48
+}
blocks/blockstore/write_cache.go
new
+45
@@ -0,0 +1,45 @@
1
+package blockstore
2
+
3
+import (
4
+ "github.com/jbenet/go-ipfs/Godeps/_workspace/src/github.com/hashicorp/golang-lru"
5
+ "github.com/jbenet/go-ipfs/blocks"
6
+ u "github.com/jbenet/go-ipfs/util"
7
+)
8
+
9
+// WriteCached returns a blockstore that caches up to |size| unique writes (bs.Put).
10
+func WriteCached(bs Blockstore, size int) (Blockstore, error) {
11
+ c, err := lru.New(size)
12
+ if err != nil {
13
+ return nil, err
14
+ }
15
+ return &writecache{blockstore: bs, cache: c}, nil
16
+}
17
+
18
+type writecache struct {
19
+ cache *lru.Cache // pointer b/c Cache contains a Mutex as value (complicates copying)
20
+ blockstore Blockstore
21
+}
22
+
23
+func (w *writecache) DeleteBlock(k u.Key) error {
24
+ w.cache.Remove(k)
25
+ return w.blockstore.DeleteBlock(k)
26
+}
27
+
28
+func (w *writecache) Has(k u.Key) (bool, error) {
29
+ if _, ok := w.cache.Get(k); ok {
30
+ return true, nil
31
+ }
32
+ return w.blockstore.Has(k)
33
+}
34
+
35
+func (w *writecache) Get(k u.Key) (*blocks.Block, error) {
36
+ return w.blockstore.Get(k)
37
+}
38
+
39
+func (w *writecache) Put(b *blocks.Block) error {
40
+ if _, ok := w.cache.Get(b.Key()); ok {
41
+ return nil
42
+ }
43
+ w.cache.Add(b.Key(), struct{}{})
44
+ return w.blockstore.Put(b)
45
+}
blocks/blockstore/write_cache_test.go
new
+88
@@ -0,0 +1,88 @@
1
+package blockstore
2
+
3
+import (
4
+ ds "github.com/jbenet/go-ipfs/Godeps/_workspace/src/github.com/jbenet/go-datastore"
5
+ syncds "github.com/jbenet/go-ipfs/Godeps/_workspace/src/github.com/jbenet/go-datastore/sync"
6
+ "github.com/jbenet/go-ipfs/blocks"
7
+ "testing"
8
+)
9
+
10
+func TestReturnsErrorWhenSizeNegative(t *testing.T) {
11
+ bs := NewBlockstore(syncds.MutexWrap(ds.NewMapDatastore()))
12
+ _, err := WriteCached(bs, -1)
13
+ if err != nil {
14
+ return
15
+ }
16
+ t.Fail()
17
+}
18
+
19
+func TestRemoveCacheEntryOnDelete(t *testing.T) {
20
+ b := blocks.NewBlock([]byte("foo"))
21
+ cd := &callbackDatastore{f: func() {}, ds: ds.NewMapDatastore()}
22
+ bs := NewBlockstore(syncds.MutexWrap(cd))
23
+ cachedbs, err := WriteCached(bs, 1)
24
+ if err != nil {
25
+ t.Fatal(err)
26
+ }
27
+ cachedbs.Put(b)
28
+
29
+ writeHitTheDatastore := false
30
+ cd.SetFunc(func() {
31
+ writeHitTheDatastore = true
32
+ })
33
+
34
+ cachedbs.DeleteBlock(b.Key())
35
+ cachedbs.Put(b)
36
+ if !writeHitTheDatastore {
37
+ t.Fail()
38
+ }
39
+}
40
+
41
+func TestElideDuplicateWrite(t *testing.T) {
42
+ cd := &callbackDatastore{f: func() {}, ds: ds.NewMapDatastore()}
43
+ bs := NewBlockstore(syncds.MutexWrap(cd))
44
+ cachedbs, err := WriteCached(bs, 1)
45
+ if err != nil {
46
+ t.Fatal(err)
47
+ }
48
+
49
+ b1 := blocks.NewBlock([]byte("foo"))
50
+
51
+ cachedbs.Put(b1)
52
+ cd.SetFunc(func() {
53
+ t.Fatal("write hit the datastore")
54
+ })
55
+ cachedbs.Put(b1)
56
+}
57
+
58
+type callbackDatastore struct {
59
+ f func()
60
+ ds ds.Datastore
61
+}
62
+
63
+func (c *callbackDatastore) SetFunc(f func()) { c.f = f }
64
+
65
+func (c *callbackDatastore) Put(key ds.Key, value interface{}) (err error) {
66
+ c.f()
67
+ return c.ds.Put(key, value)
68
+}
69
+
70
+func (c *callbackDatastore) Get(key ds.Key) (value interface{}, err error) {
71
+ c.f()
72
+ return c.ds.Get(key)
73
+}
74
+
75
+func (c *callbackDatastore) Has(key ds.Key) (exists bool, err error) {
76
+ c.f()
77
+ return c.ds.Has(key)
78
+}
79
+
80
+func (c *callbackDatastore) Delete(key ds.Key) (err error) {
81
+ c.f()
82
+ return c.ds.Delete(key)
83
+}
84
+
85
+func (c *callbackDatastore) KeyList() ([]ds.Key, error) {
86
+ c.f()
87
+ return c.ds.KeyList()
88
+}