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Golang DB.Len方法代码示例

本文整理汇总了Golang中github.com/syndtr/goleveldb/leveldb/memdb.DB.Len方法的典型用法代码示例。如果您正苦于以下问题：Golang DB.Len方法的具体用法？Golang DB.Len怎么用？Golang DB.Len使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类github.com/syndtr/goleveldb/leveldb/memdb.DB的用法示例。


在下文中一共展示了DB.Len方法的5个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Golang代码示例。

示例1: memCompaction

func (d *DB) memCompaction(mem *memdb.DB) {
	s := d.s
	c := newCMem(s)
	stats := new(cStatsStaging)

	s.printf("MemCompaction: started, size=%d entries=%d", mem.Size(), mem.Len())

	d.transact(func() (err error) {
		stats.startTimer()
		defer stats.stopTimer()
		return c.flush(mem, -1)
	})

	d.transact(func() (err error) {
		stats.startTimer()
		defer stats.stopTimer()
		return c.commit(d.journal.file.Num(), d.fseq)
	})

	stats.write = c.t.size
	d.cstats[c.level].add(stats)

	// drop frozen mem
	d.dropFrozenMem()

	c = nil
}
开发者ID:29n，项目名称:goleveldb，代码行数:27，代码来源:db_compaction.go

示例2: recoverJournal

func (db *DB) recoverJournal() error {
	// Get all tables and sort it by file number.
	journalFiles_, err := db.s.getFiles(storage.TypeJournal)
	if err != nil {
		return err
	}
	journalFiles := files(journalFiles_)
	journalFiles.sort()

	// Discard older journal.
	prev := -1
	for i, file := range journalFiles {
		if file.Num() >= db.s.stJournalNum {
			if prev >= 0 {
				i--
				journalFiles[i] = journalFiles[prev]
			}
			journalFiles = journalFiles[i:]
			break
		} else if file.Num() == db.s.stPrevJournalNum {
			prev = i
		}
	}

	var jr *journal.Reader
	var of storage.File
	var mem *memdb.DB
	batch := new(Batch)
	cm := newCMem(db.s)
	buf := new(util.Buffer)
	// Options.
	strict := db.s.o.GetStrict(opt.StrictJournal)
	checksum := db.s.o.GetStrict(opt.StrictJournalChecksum)
	writeBuffer := db.s.o.GetWriteBuffer()
	recoverJournal := func(file storage.File) error {
		db.logf("[email protected] recovering @%d", file.Num())
		reader, err := file.Open()
		if err != nil {
			return err
		}
		defer reader.Close()

		// Create/reset journal reader instance.
		if jr == nil {
			jr = journal.NewReader(reader, dropper{db.s, file}, strict, checksum)
		} else {
			jr.Reset(reader, dropper{db.s, file}, strict, checksum)
		}

		// Flush memdb and remove obsolete journal file.
		if of != nil {
			if mem.Len() > 0 {
				if err := cm.flush(mem, 0); err != nil {
					return err
				}
			}
			if err := cm.commit(file.Num(), db.seq); err != nil {
				return err
			}
			cm.reset()
			of.Remove()
			of = nil
		}

		// Replay journal to memdb.
		mem.Reset()
		for {
			r, err := jr.Next()
			if err != nil {
				if err == io.EOF {
					break
				}
				return err
			}

			buf.Reset()
			if _, err := buf.ReadFrom(r); err != nil {
				if err == io.ErrUnexpectedEOF {
					continue
				} else {
					return err
				}
			}
			if err := batch.decode(buf.Bytes()); err != nil {
				return err
			}
			if err := batch.memReplay(mem); err != nil {
				return err
			}

			// Save sequence number.
			db.seq = batch.seq + uint64(batch.len())

			// Flush it if large enough.
			if mem.Size() >= writeBuffer {
				if err := cm.flush(mem, 0); err != nil {
					return err
				}
				mem.Reset()
			}
//.........这里部分代码省略.........
开发者ID:Blueprint-Marketing，项目名称:syncthing，代码行数:101，代码来源:db.go

示例3: recoverJournal

func (d *DB) recoverJournal() error {
	s := d.s

	ff0, err := s.getFiles(storage.TypeJournal)
	if err != nil {
		return err
	}
	ff1 := files(ff0)
	ff1.sort()
	ff2 := make([]storage.File, 0, len(ff1))
	for _, file := range ff1 {
		if file.Num() >= s.stJournalNum || file.Num() == s.stPrevJournalNum {
			s.markFileNum(file.Num())
			ff2 = append(ff2, file)
		}
	}

	var jr *journal.Reader
	var of storage.File
	var mem *memdb.DB
	batch := new(Batch)
	cm := newCMem(s)
	buf := new(util.Buffer)
	// Options.
	strict := s.o.GetStrict(opt.StrictJournal)
	checksum := s.o.GetStrict(opt.StrictJournalChecksum)
	writeBuffer := s.o.GetWriteBuffer()
	recoverJournal := func(file storage.File) error {
		s.logf("[email protected] recovering @%d", file.Num())
		reader, err := file.Open()
		if err != nil {
			return err
		}
		defer reader.Close()
		if jr == nil {
			jr = journal.NewReader(reader, dropper{s, file}, strict, checksum)
		} else {
			jr.Reset(reader, dropper{s, file}, strict, checksum)
		}
		if of != nil {
			if mem.Len() > 0 {
				if err := cm.flush(mem, 0); err != nil {
					return err
				}
			}
			if err := cm.commit(file.Num(), d.seq); err != nil {
				return err
			}
			cm.reset()
			of.Remove()
			of = nil
		}
		// Reset memdb.
		mem.Reset()
		for {
			r, err := jr.Next()
			if err != nil {
				if err == io.EOF {
					break
				}
				return err
			}
			buf.Reset()
			if _, err := buf.ReadFrom(r); err != nil {
				if strict {
					return err
				}
				continue
			}
			if err := batch.decode(buf.Bytes()); err != nil {
				return err
			}
			if err := batch.memReplay(mem); err != nil {
				return err
			}
			d.seq = batch.seq + uint64(batch.len())
			if mem.Size() >= writeBuffer {
				// Large enough, flush it.
				if err := cm.flush(mem, 0); err != nil {
					return err
				}
				// Reset memdb.
				mem.Reset()
			}
		}
		of = file
		return nil
	}
	// Recover all journals.
	if len(ff2) > 0 {
		s.logf("[email protected] F·%d", len(ff2))
		mem = memdb.New(s.icmp, writeBuffer)
		for _, file := range ff2 {
			if err := recoverJournal(file); err != nil {
				return err
			}
		}
		// Flush the last journal.
		if mem.Len() > 0 {
			if err := cm.flush(mem, 0); err != nil {
//.........这里部分代码省略.........
开发者ID:ZSIT，项目名称:syncthing，代码行数:101，代码来源:db.go

示例4: recoverLog

func (d *DB) recoverLog() (err error) {
	s := d.s
	icmp := s.cmp

	s.printf("LogRecovery: started, min=%d", s.stLogNum)

	var mem *memdb.DB
	batch := new(Batch)
	cm := newCMem(s)

	logs, skip := files(s.getFiles(desc.TypeLog)), 0
	logs.sort()
	for _, log := range logs {
		if log.Num() < s.stLogNum {
			skip++
			continue
		}
		s.markFileNum(log.Num())
	}

	var r, fr *logReader
	for _, log := range logs[skip:] {
		s.printf("LogRecovery: recovering, num=%d", log.Num())

		r, err = newLogReader(log, true, s.logDropFunc("log", log.Num()))
		if err != nil {
			return
		}

		if mem != nil {
			if mem.Len() > 0 {
				err = cm.flush(mem, 0)
				if err != nil {
					return
				}
			}

			err = cm.commit(r.file.Num(), d.seq)
			if err != nil {
				return
			}

			cm.reset()

			fr.remove()
			fr = nil
		}

		mem = memdb.New(icmp)

		for r.log.Next() {
			err = batch.decode(r.log.Record())
			if err != nil {
				return
			}

			err = batch.memReplay(mem)
			if err != nil {
				return
			}

			d.seq = batch.seq + uint64(batch.len())

			if mem.Size() > s.o.GetWriteBuffer() {
				// flush to table
				err = cm.flush(mem, 0)
				if err != nil {
					return
				}

				// create new memdb
				mem = memdb.New(icmp)
			}
		}

		err = r.log.Error()
		if err != nil {
			return
		}

		r.close()
		fr = r
	}

	// create new log
	_, err = d.newMem()
	if err != nil {
		return
	}

	if mem != nil && mem.Len() > 0 {
		err = cm.flush(mem, 0)
		if err != nil {
			return
		}
	}

	err = cm.commit(d.log.file.Num(), d.seq)
	if err != nil {
		return
//.........这里部分代码省略.........
开发者ID:yufeng108，项目名称:goleveldb，代码行数:101，代码来源:db.go

示例5: recoverJournal

func (d *DB) recoverJournal() (err error) {
	s := d.s
	icmp := s.cmp

	s.printf("JournalRecovery: started, min=%d", s.stJournalNum)

	var mem *memdb.DB
	batch := new(Batch)
	cm := newCMem(s)

	journals := files(s.getFiles(storage.TypeJournal))
	journals.sort()
	rJournals := make([]storage.File, 0, len(journals))
	for _, journal := range journals {
		if journal.Num() >= s.stJournalNum || journal.Num() == s.stPrevJournalNum {
			s.markFileNum(journal.Num())
			rJournals = append(rJournals, journal)
		}
	}

	var r, fr *journalReader
	for _, journal := range rJournals {
		s.printf("JournalRecovery: recovering, num=%d", journal.Num())

		r, err = newJournalReader(journal, true, s.journalDropFunc("journal", journal.Num()))
		if err != nil {
			return
		}

		if mem != nil {
			if mem.Len() > 0 {
				err = cm.flush(mem, 0)
				if err != nil {
					return
				}
			}

			err = cm.commit(r.file.Num(), d.seq)
			if err != nil {
				return
			}

			cm.reset()

			fr.remove()
			fr = nil
		}

		mem = memdb.New(icmp)

		for r.journal.Next() {
			err = batch.decode(r.journal.Record())
			if err != nil {
				return
			}

			err = batch.memReplay(mem)
			if err != nil {
				return
			}

			d.seq = batch.seq + uint64(batch.len())

			if mem.Size() > s.o.GetWriteBuffer() {
				// flush to table
				err = cm.flush(mem, 0)
				if err != nil {
					return
				}

				// create new memdb
				mem = memdb.New(icmp)
			}
		}

		err = r.journal.Error()
		if err != nil {
			return
		}

		r.close()
		fr = r
	}

	// create new journal
	_, err = d.newMem()
	if err != nil {
		return
	}

	if mem != nil && mem.Len() > 0 {
		err = cm.flush(mem, 0)
		if err != nil {
			return
		}
	}

	err = cm.commit(d.journal.file.Num(), d.seq)
	if err != nil {
		return
//.........这里部分代码省略.........
开发者ID:JensRantil，项目名称:goleveldb，代码行数:101，代码来源:db.go


注：本文中的github.com/syndtr/goleveldb/leveldb/memdb.DB.Len方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台，相关代码片段筛选自各路编程大神贡献的开源项目，源码版权归原作者所有，传播和使用请参考对应项目的License；未经允许，请勿转载。