-
Notifications
You must be signed in to change notification settings - Fork 0
/
coprocessor.go
550 lines (497 loc) · 13.4 KB
/
coprocessor.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
// Copyright 2016 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.
package tikv
import (
"bytes"
"fmt"
"sync"
"time"
log "github.com/Sirupsen/logrus"
"github.com/juju/errors"
"github.com/pingcap/kvproto/pkg/coprocessor"
"github.com/pingcap/kvproto/pkg/kvrpcpb"
"github.com/pingcap/tidb/kv"
"github.com/pingcap/tidb/store/tikv/tikvrpc"
"github.com/pingcap/tidb/util/goroutine_pool"
"github.com/pingcap/tipb/go-tipb"
goctx "golang.org/x/net/context"
)
var copIteratorGP = gp.New(time.Minute)
// CopClient is coprocessor client.
type CopClient struct {
store *tikvStore
}
// IsRequestTypeSupported checks whether reqType is supported.
func (c *CopClient) IsRequestTypeSupported(reqType, subType int64) bool {
switch reqType {
case kv.ReqTypeSelect, kv.ReqTypeIndex:
switch subType {
case kv.ReqSubTypeGroupBy, kv.ReqSubTypeBasic, kv.ReqSubTypeTopN:
return true
default:
return c.supportExpr(tipb.ExprType(subType))
}
case kv.ReqTypeDAG:
return c.supportExpr(tipb.ExprType(subType))
case kv.ReqTypeAnalyze:
return true
}
return false
}
func (c *CopClient) supportExpr(exprType tipb.ExprType) bool {
switch exprType {
case tipb.ExprType_Null, tipb.ExprType_Int64, tipb.ExprType_Uint64, tipb.ExprType_String, tipb.ExprType_Bytes,
tipb.ExprType_MysqlDuration, tipb.ExprType_MysqlTime, tipb.ExprType_MysqlDecimal,
tipb.ExprType_ColumnRef:
return true
// logic operators.
case tipb.ExprType_And, tipb.ExprType_Or, tipb.ExprType_Not:
return true
// compare operators.
case tipb.ExprType_LT, tipb.ExprType_LE, tipb.ExprType_EQ, tipb.ExprType_NE,
tipb.ExprType_GE, tipb.ExprType_GT, tipb.ExprType_NullEQ,
tipb.ExprType_In, tipb.ExprType_ValueList, tipb.ExprType_IsNull,
tipb.ExprType_Like:
return true
// arithmetic operators.
case tipb.ExprType_Plus, tipb.ExprType_Div, tipb.ExprType_Minus, tipb.ExprType_Mul:
return true
// control functions
case tipb.ExprType_Case, tipb.ExprType_If, tipb.ExprType_IfNull, tipb.ExprType_Coalesce:
return true
// aggregate functions.
case tipb.ExprType_Count, tipb.ExprType_First, tipb.ExprType_Max, tipb.ExprType_Min, tipb.ExprType_Sum, tipb.ExprType_Avg:
return true
// json functions.
case tipb.ExprType_JsonType, tipb.ExprType_JsonExtract, tipb.ExprType_JsonUnquote,
tipb.ExprType_JsonObject, tipb.ExprType_JsonArray, tipb.ExprType_JsonMerge,
tipb.ExprType_JsonSet, tipb.ExprType_JsonInsert, tipb.ExprType_JsonReplace, tipb.ExprType_JsonRemove:
return true
case kv.ReqSubTypeDesc:
return true
case kv.ReqSubTypeSignature:
return true
default:
return false
}
}
// Send builds the request and gets the coprocessor iterator response.
func (c *CopClient) Send(ctx goctx.Context, req *kv.Request) kv.Response {
coprocessorCounter.WithLabelValues("send").Inc()
bo := NewBackoffer(copBuildTaskMaxBackoff, ctx)
tasks, err := buildCopTasks(bo, c.store.regionCache, &copRanges{mid: req.KeyRanges}, req.Desc)
if err != nil {
return copErrorResponse{err}
}
it := &copIterator{
store: c.store,
req: req,
concurrency: req.Concurrency,
finished: make(chan struct{}),
}
it.tasks = tasks
if it.concurrency > len(tasks) {
it.concurrency = len(tasks)
}
if it.concurrency < 1 {
// Make sure that there is at least one worker.
it.concurrency = 1
}
if !it.req.KeepOrder {
it.respChan = make(chan copResponse, it.concurrency)
}
it.run(ctx)
return it
}
// copTask contains a related Region and KeyRange for a kv.Request.
type copTask struct {
region RegionVerID
ranges *copRanges
respChan chan copResponse
storeAddr string
}
func (r *copTask) String() string {
return fmt.Sprintf("region(%d %d %d) ranges(%d) store(%s)",
r.region.id, r.region.confVer, r.region.ver, r.ranges.len(), r.storeAddr)
}
// copRanges is like []kv.KeyRange, but may has extra elements at head/tail.
// It's for avoiding alloc big slice during build copTask.
type copRanges struct {
first *kv.KeyRange
mid []kv.KeyRange
last *kv.KeyRange
}
func (r *copRanges) String() string {
var s string
r.do(func(ran *kv.KeyRange) {
s += fmt.Sprintf("[%q, %q]", ran.StartKey, ran.EndKey)
})
return s
}
func (r *copRanges) len() int {
var l int
if r.first != nil {
l++
}
l += len(r.mid)
if r.last != nil {
l++
}
return l
}
func (r *copRanges) at(i int) kv.KeyRange {
if r.first != nil {
if i == 0 {
return *r.first
}
i--
}
if i < len(r.mid) {
return r.mid[i]
}
return *r.last
}
func (r *copRanges) slice(from, to int) *copRanges {
var ran copRanges
if r.first != nil {
if from == 0 && to > 0 {
ran.first = r.first
}
if from > 0 {
from--
}
if to > 0 {
to--
}
}
if to <= len(r.mid) {
ran.mid = r.mid[from:to]
} else {
if from <= len(r.mid) {
ran.mid = r.mid[from:]
}
if from < to {
ran.last = r.last
}
}
return &ran
}
func (r *copRanges) do(f func(ran *kv.KeyRange)) {
if r.first != nil {
f(r.first)
}
for _, ran := range r.mid {
f(&ran)
}
if r.last != nil {
f(r.last)
}
}
func (r *copRanges) toPBRanges() []*coprocessor.KeyRange {
ranges := make([]*coprocessor.KeyRange, 0, r.len())
r.do(func(ran *kv.KeyRange) {
ranges = append(ranges, &coprocessor.KeyRange{
Start: ran.StartKey,
End: ran.EndKey,
})
})
return ranges
}
func buildCopTasks(bo *Backoffer, cache *RegionCache, ranges *copRanges, desc bool) ([]*copTask, error) {
coprocessorCounter.WithLabelValues("build_task").Inc()
start := time.Now()
rangesLen := ranges.len()
var tasks []*copTask
appendTask := func(region RegionVerID, ranges *copRanges) {
tasks = append(tasks, &copTask{
region: region,
ranges: ranges,
respChan: make(chan copResponse, 1),
})
}
for ranges.len() > 0 {
loc, err := cache.LocateKey(bo, ranges.at(0).StartKey)
if err != nil {
return nil, errors.Trace(err)
}
// Iterate to the first range that is not complete in the region.
var i int
for ; i < ranges.len(); i++ {
r := ranges.at(i)
if !(loc.Contains(r.EndKey) || bytes.Equal(loc.EndKey, r.EndKey)) {
break
}
}
// All rest ranges belong to the same region.
if i == ranges.len() {
appendTask(loc.Region, ranges)
break
}
r := ranges.at(i)
if loc.Contains(r.StartKey) {
// Part of r is not in the region. We need to split it.
taskRanges := ranges.slice(0, i)
taskRanges.last = &kv.KeyRange{
StartKey: r.StartKey,
EndKey: loc.EndKey,
}
appendTask(loc.Region, taskRanges)
ranges = ranges.slice(i+1, ranges.len())
ranges.first = &kv.KeyRange{
StartKey: loc.EndKey,
EndKey: r.EndKey,
}
} else {
// rs[i] is not in the region.
appendTask(loc.Region, ranges.slice(0, i))
ranges = ranges.slice(i, ranges.len())
}
}
if desc {
reverseTasks(tasks)
}
if elapsed := time.Since(start); elapsed > time.Millisecond*500 {
log.Warnf("buildCopTasks takes too much time (%v), range len %v, task len %v", elapsed, rangesLen, len(tasks))
}
txnRegionsNumHistogram.WithLabelValues("coprocessor").Observe(float64(len(tasks)))
return tasks, nil
}
func reverseTasks(tasks []*copTask) {
for i := 0; i < len(tasks)/2; i++ {
j := len(tasks) - i - 1
tasks[i], tasks[j] = tasks[j], tasks[i]
}
}
type copIterator struct {
store *tikvStore
req *kv.Request
concurrency int
finished chan struct{}
// If keepOrder, results are stored in copTask.respChan, read them out one by one.
tasks []*copTask
curr int
// Otherwise, results are stored in respChan.
respChan chan copResponse
wg sync.WaitGroup
}
type copResponse struct {
*coprocessor.Response
err error
}
const minLogCopTaskTime = 300 * time.Millisecond
// work is a worker function that get a copTask from channel, handle it and
// send the result back.
func (it *copIterator) work(ctx goctx.Context, taskCh <-chan *copTask) {
defer it.wg.Done()
for task := range taskCh {
bo := NewBackoffer(copNextMaxBackoff, ctx)
startTime := time.Now()
resps := it.handleTask(bo, task)
costTime := time.Since(startTime)
if costTime > minLogCopTaskTime {
log.Infof("[TIME_COP_TASK] %s%s %s", costTime, bo, task)
}
coprocessorHistogram.Observe(costTime.Seconds())
if bo.totalSleep > 0 {
backoffHistogram.Observe(float64(bo.totalSleep) / 1000)
}
var ch chan copResponse
if !it.req.KeepOrder {
ch = it.respChan
} else {
ch = task.respChan
}
for _, resp := range resps {
select {
case ch <- resp:
case <-ctx.Done():
return
case <-it.finished:
return
}
}
if it.req.KeepOrder {
close(ch)
}
}
}
func (it *copIterator) run(ctx goctx.Context) {
taskCh := make(chan *copTask, 1)
it.wg.Add(it.concurrency)
// Start it.concurrency number of workers to handle cop requests.
for i := 0; i < it.concurrency; i++ {
copIteratorGP.Go(func() {
childCtx, cancel := goctx.WithCancel(ctx)
defer cancel()
it.work(childCtx, taskCh)
})
}
copIteratorGP.Go(func() {
// Send tasks to feed the worker goroutines.
childCtx, cancel := goctx.WithCancel(ctx)
defer cancel()
for _, t := range it.tasks {
finished, canceled := it.sendToTaskCh(childCtx, t, taskCh)
if finished || canceled {
break
}
}
close(taskCh)
// Wait for worker goroutines to exit.
it.wg.Wait()
if !it.req.KeepOrder {
close(it.respChan)
}
})
}
func (it *copIterator) sendToTaskCh(ctx goctx.Context, t *copTask, taskCh chan<- *copTask) (finished bool, canceled bool) {
select {
case taskCh <- t:
case <-it.finished:
finished = true
case <-ctx.Done():
canceled = true
}
return
}
// Next returns next coprocessor result.
func (it *copIterator) Next() ([]byte, error) {
coprocessorCounter.WithLabelValues("next").Inc()
var (
resp copResponse
ok bool
)
// If data order matters, response should be returned in the same order as copTask slice.
// Otherwise all responses are returned from a single channel.
if !it.req.KeepOrder {
// Get next fetched resp from chan
resp, ok = <-it.respChan
if !ok {
return nil, nil
}
} else {
for {
if it.curr >= len(it.tasks) {
// Resp will be nil if iterator is finished.
return nil, nil
}
task := it.tasks[it.curr]
resp, ok = <-task.respChan
if ok {
break
}
// Switch to next task.
it.tasks[it.curr] = nil
it.curr++
}
}
if resp.err != nil {
return nil, errors.Trace(resp.err)
}
if resp.Data == nil {
return []byte{}, nil
}
err := it.store.CheckVisibility(it.req.StartTs)
if err != nil {
return nil, errors.Trace(err)
}
return resp.Data, nil
}
// handleTask handles single copTask.
func (it *copIterator) handleTask(bo *Backoffer, task *copTask) []copResponse {
coprocessorCounter.WithLabelValues("handle_task").Inc()
sender := NewRegionRequestSender(it.store.regionCache, it.store.client)
for {
select {
case <-it.finished:
return nil
default:
}
req := &tikvrpc.Request{
Type: tikvrpc.CmdCop,
Cop: &coprocessor.Request{
Tp: it.req.Tp,
Data: it.req.Data,
Ranges: task.ranges.toPBRanges(),
},
Context: kvrpcpb.Context{
IsolationLevel: pbIsolationLevel(it.req.IsolationLevel),
Priority: kvPriorityToCommandPri(it.req.Priority),
NotFillCache: it.req.NotFillCache,
},
}
resp, err := sender.SendReq(bo, req, task.region, readTimeoutMedium)
if err != nil {
return []copResponse{{err: errors.Trace(err)}}
}
if regionErr := resp.Cop.GetRegionError(); regionErr != nil {
err = bo.Backoff(boRegionMiss, errors.New(regionErr.String()))
if err != nil {
return []copResponse{{err: errors.Trace(err)}}
}
return it.handleRegionErrorTask(bo, task)
}
if e := resp.Cop.GetLocked(); e != nil {
log.Debugf("coprocessor encounters lock: %v", e)
ok, err1 := it.store.lockResolver.ResolveLocks(bo, []*Lock{newLock(e)})
if err1 != nil {
return []copResponse{{err: errors.Trace(err1)}}
}
if !ok {
err = bo.Backoff(boTxnLockFast, errors.New(e.String()))
if err != nil {
return []copResponse{{err: errors.Trace(err)}}
}
}
continue
}
if e := resp.Cop.GetOtherError(); e != "" {
err = errors.Errorf("other error: %s", e)
log.Warnf("coprocessor err: %v", err)
return []copResponse{{err: errors.Trace(err)}}
}
task.storeAddr = sender.storeAddr
return []copResponse{{Response: resp.Cop}}
}
}
// handleRegionErrorTask handles current task. It may be split into multiple tasks (in region split scenario).
func (it *copIterator) handleRegionErrorTask(bo *Backoffer, task *copTask) []copResponse {
coprocessorCounter.WithLabelValues("rebuild_task").Inc()
newTasks, err := buildCopTasks(bo, it.store.regionCache, task.ranges, it.req.Desc)
if err != nil {
return []copResponse{{err: errors.Trace(err)}}
}
if newTasks == nil {
// TODO: check this, this should never happen.
return nil
}
var ret []copResponse
for _, t := range newTasks {
resp := it.handleTask(bo, t)
ret = append(ret, resp...)
}
return ret
}
func (it *copIterator) Close() error {
close(it.finished)
it.wg.Wait()
return nil
}
// copErrorResponse returns error when calling Next()
type copErrorResponse struct{ error }
func (it copErrorResponse) Next() ([]byte, error) {
return nil, it.error
}
func (it copErrorResponse) Close() error {
return nil
}