aboutsummaryrefslogtreecommitdiffstats
path: root/ethdb/database.go
blob: 001d8f0bb94315757d3bfef97b4d7c6fb7d2fce6 (plain) (blame)
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
// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package ethdb

import (
    "fmt"
    "strconv"
    "strings"
    "sync"
    "time"

    "github.com/ethereum/go-ethereum/log"
    "github.com/ethereum/go-ethereum/metrics"
    "github.com/syndtr/goleveldb/leveldb"
    "github.com/syndtr/goleveldb/leveldb/errors"
    "github.com/syndtr/goleveldb/leveldb/filter"
    "github.com/syndtr/goleveldb/leveldb/iterator"
    "github.com/syndtr/goleveldb/leveldb/opt"
    "github.com/syndtr/goleveldb/leveldb/util"
)

const (
    writeDelayNThreshold       = 200
    writeDelayThreshold        = 350 * time.Millisecond
    writeDelayWarningThrottler = 1 * time.Minute
)

var OpenFileLimit = 64

type LDBDatabase struct {
    fn string      // filename for reporting
    db *leveldb.DB // LevelDB instance

    compTimeMeter    metrics.Meter // Meter for measuring the total time spent in database compaction
    compReadMeter    metrics.Meter // Meter for measuring the data read during compaction
    compWriteMeter   metrics.Meter // Meter for measuring the data written during compaction
    writeDelayNMeter metrics.Meter // Meter for measuring the write delay number due to database compaction
    writeDelayMeter  metrics.Meter // Meter for measuring the write delay duration due to database compaction
    diskReadMeter    metrics.Meter // Meter for measuring the effective amount of data read
    diskWriteMeter   metrics.Meter // Meter for measuring the effective amount of data written

    quitLock sync.Mutex      // Mutex protecting the quit channel access
    quitChan chan chan error // Quit channel to stop the metrics collection before closing the database

    log log.Logger // Contextual logger tracking the database path
}

// NewLDBDatabase returns a LevelDB wrapped object.
func NewLDBDatabase(file string, cache int, handles int) (*LDBDatabase, error) {
    logger := log.New("database", file)

    // Ensure we have some minimal caching and file guarantees
    if cache < 16 {
        cache = 16
    }
    if handles < 16 {
        handles = 16
    }
    logger.Info("Allocated cache and file handles", "cache", cache, "handles", handles)

    // Open the db and recover any potential corruptions
    db, err := leveldb.OpenFile(file, &opt.Options{
        OpenFilesCacheCapacity: handles,
        BlockCacheCapacity:     cache / 2 * opt.MiB,
        WriteBuffer:            cache / 4 * opt.MiB, // Two of these are used internally
        Filter:                 filter.NewBloomFilter(10),
    })
    if _, corrupted := err.(*errors.ErrCorrupted); corrupted {
        db, err = leveldb.RecoverFile(file, nil)
    }
    // (Re)check for errors and abort if opening of the db failed
    if err != nil {
        return nil, err
    }
    return &LDBDatabase{
        fn:  file,
        db:  db,
        log: logger,
    }, nil
}

// Path returns the path to the database directory.
func (db *LDBDatabase) Path() string {
    return db.fn
}

// Put puts the given key / value to the queue
func (db *LDBDatabase) Put(key []byte, value []byte) error {
    return db.db.Put(key, value, nil)
}

func (db *LDBDatabase) Has(key []byte) (bool, error) {
    return db.db.Has(key, nil)
}

// Get returns the given key if it's present.
func (db *LDBDatabase) Get(key []byte) ([]byte, error) {
    dat, err := db.db.Get(key, nil)
    if err != nil {
        return nil, err
    }
    return dat, nil
}

// Delete deletes the key from the queue and database
func (db *LDBDatabase) Delete(key []byte) error {
    return db.db.Delete(key, nil)
}

func (db *LDBDatabase) NewIterator() iterator.Iterator {
    return db.db.NewIterator(nil, nil)
}

// NewIteratorWithPrefix returns a iterator to iterate over subset of database content with a particular prefix.
func (db *LDBDatabase) NewIteratorWithPrefix(prefix []byte) iterator.Iterator {
    return db.db.NewIterator(util.BytesPrefix(prefix), nil)
}

func (db *LDBDatabase) Close() {
    // Stop the metrics collection to avoid internal database races
    db.quitLock.Lock()
    defer db.quitLock.Unlock()

    if db.quitChan != nil {
        errc := make(chan error)
        db.quitChan <- errc
        if err := <-errc; err != nil {
            db.log.Error("Metrics collection failed", "err", err)
        }
    }
    err := db.db.Close()
    if err == nil {
        db.log.Info("Database closed")
    } else {
        db.log.Error("Failed to close database", "err", err)
    }
}

func (db *LDBDatabase) LDB() *leveldb.DB {
    return db.db
}

// Meter configures the database metrics collectors and
func (db *LDBDatabase) Meter(prefix string) {
    if metrics.Enabled {
        // Initialize all the metrics collector at the requested prefix
        db.compTimeMeter = metrics.NewRegisteredMeter(prefix+"compact/time", nil)
        db.compReadMeter = metrics.NewRegisteredMeter(prefix+"compact/input", nil)
        db.compWriteMeter = metrics.NewRegisteredMeter(prefix+"compact/output", nil)
        db.diskReadMeter = metrics.NewRegisteredMeter(prefix+"disk/read", nil)
        db.diskWriteMeter = metrics.NewRegisteredMeter(prefix+"disk/write", nil)
    }
    // Initialize write delay metrics no matter we are in metric mode or not.
    db.writeDelayMeter = metrics.NewRegisteredMeter(prefix+"compact/writedelay/duration", nil)
    db.writeDelayNMeter = metrics.NewRegisteredMeter(prefix+"compact/writedelay/counter", nil)

    // Create a quit channel for the periodic collector and run it
    db.quitLock.Lock()
    db.quitChan = make(chan chan error)
    db.quitLock.Unlock()

    go db.meter(3 * time.Second)
}

// meter periodically retrieves internal leveldb counters and reports them to
// the metrics subsystem.
//
// This is how a stats table look like (currently):
//   Compactions
//    Level |   Tables   |    Size(MB)   |    Time(sec)  |    Read(MB)   |   Write(MB)
//   -------+------------+---------------+---------------+---------------+---------------
//      0   |          0 |       0.00000 |       1.27969 |       0.00000 |      12.31098
//      1   |         85 |     109.27913 |      28.09293 |     213.92493 |     214.26294
//      2   |        523 |    1000.37159 |       7.26059 |      66.86342 |      66.77884
//      3   |        570 |    1113.18458 |       0.00000 |       0.00000 |       0.00000
//
// This is how the write delay look like (currently):
// DelayN:5 Delay:406.604657ms
//
// This is how the iostats look like (currently):
// Read(MB):3895.04860 Write(MB):3654.64712
func (db *LDBDatabase) meter(refresh time.Duration) {
    // Create the counters to store current and previous compaction values
    compactions := make([][]float64, 2)
    for i := 0; i < 2; i++ {
        compactions[i] = make([]float64, 3)
    }
    // Create storage for iostats.
    var iostats [2]float64

    // Create storage and warning log tracer for write delay.
    var (
        delaystats      [2]int64
        lastWriteDelay  time.Time
        lastWriteDelayN time.Time
    )

    // Iterate ad infinitum and collect the stats
    for i := 1; ; i++ {
        // Retrieve the database stats
        stats, err := db.db.GetProperty("leveldb.stats")
        if err != nil {
            db.log.Error("Failed to read database stats", "err", err)
            return
        }
        // Find the compaction table, skip the header
        lines := strings.Split(stats, "\n")
        for len(lines) > 0 && strings.TrimSpace(lines[0]) != "Compactions" {
            lines = lines[1:]
        }
        if len(lines) <= 3 {
            db.log.Error("Compaction table not found")
            return
        }
        lines = lines[3:]

        // Iterate over all the table rows, and accumulate the entries
        for j := 0; j < len(compactions[i%2]); j++ {
            compactions[i%2][j] = 0
        }
        for _, line := range lines {
            parts := strings.Split(line, "|")
            if len(parts) != 6 {
                break
            }
            for idx, counter := range parts[3:] {
                value, err := strconv.ParseFloat(strings.TrimSpace(counter), 64)
                if err != nil {
                    db.log.Error("Compaction entry parsing failed", "err", err)
                    return
                }
                compactions[i%2][idx] += value
            }
        }
        // Update all the requested meters
        if db.compTimeMeter != nil {
            db.compTimeMeter.Mark(int64((compactions[i%2][0] - compactions[(i-1)%2][0]) * 1000 * 1000 * 1000))
        }
        if db.compReadMeter != nil {
            db.compReadMeter.Mark(int64((compactions[i%2][1] - compactions[(i-1)%2][1]) * 1024 * 1024))
        }
        if db.compWriteMeter != nil {
            db.compWriteMeter.Mark(int64((compactions[i%2][2] - compactions[(i-1)%2][2]) * 1024 * 1024))
        }

        // Retrieve the write delay statistic
        writedelay, err := db.db.GetProperty("leveldb.writedelay")
        if err != nil {
            db.log.Error("Failed to read database write delay statistic", "err", err)
            return
        }
        var (
            delayN        int64
            delayDuration string
            duration      time.Duration
        )
        if n, err := fmt.Sscanf(writedelay, "DelayN:%d Delay:%s", &delayN, &delayDuration); n != 2 || err != nil {
            db.log.Error("Write delay statistic not found")
            return
        }
        duration, err = time.ParseDuration(delayDuration)
        if err != nil {
            db.log.Error("Failed to parse delay duration", "err", err)
            return
        }
        if db.writeDelayNMeter != nil {
            db.writeDelayNMeter.Mark(delayN - delaystats[0])
            // If the write delay number been collected in the last minute exceeds the predefined threshold,
            // print a warning log here.
            // If a warning that db performance is laggy has been displayed,
            // any subsequent warnings will be withhold for 1 minute to don't overwhelm the user.
            if int(db.writeDelayNMeter.Rate1()) > writeDelayNThreshold &&
                time.Now().After(lastWriteDelayN.Add(writeDelayWarningThrottler)) {
                db.log.Warn("Write delay number exceeds the threshold (200 per second) in the last minute")
                lastWriteDelayN = time.Now()
            }
        }
        if db.writeDelayMeter != nil {
            db.writeDelayMeter.Mark(duration.Nanoseconds() - delaystats[1])
            // If the write delay duration been collected in the last minute exceeds the predefined threshold,
            // print a warning log here.
            // If a warning that db performance is laggy has been displayed,
            // any subsequent warnings will be withhold for 1 minute to don't overwhelm the user.
            if int64(db.writeDelayMeter.Rate1()) > writeDelayThreshold.Nanoseconds() &&
                time.Now().After(lastWriteDelay.Add(writeDelayWarningThrottler)) {
                db.log.Warn("Write delay duration exceeds the threshold (35% of the time) in the last minute")
                lastWriteDelay = time.Now()
            }
        }
        delaystats[0], delaystats[1] = delayN, duration.Nanoseconds()

        // Retrieve the database iostats.
        ioStats, err := db.db.GetProperty("leveldb.iostats")
        if err != nil {
            db.log.Error("Failed to read database iostats", "err", err)
            return
        }
        parts := strings.Split(ioStats, " ")
        if len(parts) < 2 {
            db.log.Error("Bad syntax of ioStats", "ioStats", ioStats)
            return
        }
        r := strings.Split(parts[0], ":")
        if len(r) < 2 {
            db.log.Error("Bad syntax of read entry", "entry", parts[0])
            return
        }
        read, err := strconv.ParseFloat(r[1], 64)
        if err != nil {
            db.log.Error("Read entry parsing failed", "err", err)
            return
        }
        w := strings.Split(parts[1], ":")
        if len(w) < 2 {
            db.log.Error("Bad syntax of write entry", "entry", parts[1])
            return
        }
        write, err := strconv.ParseFloat(w[1], 64)
        if err != nil {
            db.log.Error("Write entry parsing failed", "err", err)
            return
        }
        if db.diskReadMeter != nil {
            db.diskReadMeter.Mark(int64((read - iostats[0]) * 1024 * 1024))
        }
        if db.diskWriteMeter != nil {
            db.diskWriteMeter.Mark(int64((write - iostats[1]) * 1024 * 1024))
        }
        iostats[0] = read
        iostats[1] = write

        // Sleep a bit, then repeat the stats collection
        select {
        case errc := <-db.quitChan:
            // Quit requesting, stop hammering the database
            errc <- nil
            return

        case <-time.After(refresh):
            // Timeout, gather a new set of stats
        }
    }
}

func (db *LDBDatabase) NewBatch() Batch {
    return &ldbBatch{db: db.db, b: new(leveldb.Batch)}
}

type ldbBatch struct {
    db   *leveldb.DB
    b    *leveldb.Batch
    size int
}

func (b *ldbBatch) Put(key, value []byte) error {
    b.b.Put(key, value)
    b.size += len(value)
    return nil
}

func (b *ldbBatch) Write() error {
    return b.db.Write(b.b, nil)
}

func (b *ldbBatch) ValueSize() int {
    return b.size
}

func (b *ldbBatch) Reset() {
    b.b.Reset()
    b.size = 0
}

type table struct {
    db     Database
    prefix string
}

// NewTable returns a Database object that prefixes all keys with a given
// string.
func NewTable(db Database, prefix string) Database {
    return &table{
        db:     db,
        prefix: prefix,
    }
}

func (dt *table) Put(key []byte, value []byte) error {
    return dt.db.Put(append([]byte(dt.prefix), key...), value)
}

func (dt *table) Has(key []byte) (bool, error) {
    return dt.db.Has(append([]byte(dt.prefix), key...))
}

func (dt *table) Get(key []byte) ([]byte, error) {
    return dt.db.Get(append([]byte(dt.prefix), key...))
}

func (dt *table) Delete(key []byte) error {
    return dt.db.Delete(append([]byte(dt.prefix), key...))
}

func (dt *table) Close() {
    // Do nothing; don't close the underlying DB.
}

type tableBatch struct {
    batch  Batch
    prefix string
}

// NewTableBatch returns a Batch object which prefixes all keys with a given string.
func NewTableBatch(db Database, prefix string) Batch {
    return &tableBatch{db.NewBatch(), prefix}
}

func (dt *table) NewBatch() Batch {
    return &tableBatch{dt.db.NewBatch(), dt.prefix}
}

func (tb *tableBatch) Put(key, value []byte) error {
    return tb.batch.Put(append([]byte(tb.prefix), key...), value)
}

func (tb *tableBatch) Write() error {
    return tb.batch.Write()
}

func (tb *tableBatch) ValueSize() int {
    return tb.batch.ValueSize()
}

func (tb *tableBatch) Reset() {
    tb.batch.Reset()
}