diff options
Diffstat (limited to 'vendor/github.com/syndtr/goleveldb/leveldb/version.go')
| -rw-r--r-- | vendor/github.com/syndtr/goleveldb/leveldb/version.go | 81 |
1 files changed, 63 insertions, 18 deletions
diff --git a/vendor/github.com/syndtr/goleveldb/leveldb/version.go b/vendor/github.com/syndtr/goleveldb/leveldb/version.go index 73f272a..9535e35 100644 --- a/vendor/github.com/syndtr/goleveldb/leveldb/version.go +++ b/vendor/github.com/syndtr/goleveldb/leveldb/version.go @@ -9,6 +9,7 @@ package leveldb import ( "fmt" "sync/atomic" + "time" "unsafe" "github.com/syndtr/goleveldb/leveldb/iterator" @@ -22,7 +23,8 @@ type tSet struct { } type version struct { - s *session + id int64 // unique monotonous increasing version id + s *session levels []tFiles @@ -39,8 +41,11 @@ type version struct { released bool } +// newVersion creates a new version with an unique monotonous increasing id. func newVersion(s *session) *version { - return &version{s: s} + id := atomic.AddInt64(&s.ntVersionId, 1) + nv := &version{s: s, id: id - 1} + return nv } func (v *version) incref() { @@ -50,11 +55,11 @@ func (v *version) incref() { v.ref++ if v.ref == 1 { - // Incr file ref. - for _, tt := range v.levels { - for _, t := range tt { - v.s.addFileRef(t.fd, 1) - } + select { + case v.s.refCh <- &vTask{vid: v.id, files: v.levels, created: time.Now()}: + // We can use v.levels directly here since it is immutable. + case <-v.s.closeC: + v.s.log("reference loop already exist") } } } @@ -66,13 +71,11 @@ func (v *version) releaseNB() { } else if v.ref < 0 { panic("negative version ref") } - - for _, tt := range v.levels { - for _, t := range tt { - if v.s.addFileRef(t.fd, -1) == 0 { - v.s.tops.remove(t) - } - } + select { + case v.s.relCh <- &vTask{vid: v.id, files: v.levels, created: time.Now()}: + // We can use v.levels directly here since it is immutable. + case <-v.s.closeC: + v.s.log("reference loop already exist") } v.released = true @@ -141,6 +144,7 @@ func (v *version) get(aux tFiles, ikey internalKey, ro *opt.ReadOptions, noValue } ukey := ikey.ukey() + sampleSeeks := !v.s.o.GetDisableSeeksCompaction() var ( tset *tSet @@ -158,7 +162,7 @@ func (v *version) get(aux tFiles, ikey internalKey, ro *opt.ReadOptions, noValue // Since entries never hop across level, finding key/value // in smaller level make later levels irrelevant. v.walkOverlapping(aux, ikey, func(level int, t *tFile) bool { - if level >= 0 && !tseek { + if sampleSeeks && level >= 0 && !tseek { if tset == nil { tset = &tSet{level, t} } else { @@ -273,10 +277,10 @@ func (v *version) newStaging() *versionStaging { } // Spawn a new version based on this version. -func (v *version) spawn(r *sessionRecord) *version { +func (v *version) spawn(r *sessionRecord, trivial bool) *version { staging := v.newStaging() staging.commit(r) - return staging.finish() + return staging.finish(trivial) } func (v *version) fillRecord(r *sessionRecord) { @@ -446,7 +450,7 @@ func (p *versionStaging) commit(r *sessionRecord) { } } -func (p *versionStaging) finish() *version { +func (p *versionStaging) finish(trivial bool) *version { // Build new version. nv := newVersion(p.base.s) numLevel := len(p.levels) @@ -463,6 +467,12 @@ func (p *versionStaging) finish() *version { if level < len(p.levels) { scratch := p.levels[level] + // Short circuit if there is no change at all. + if len(scratch.added) == 0 && len(scratch.deleted) == 0 { + nv.levels[level] = baseTabels + continue + } + var nt tFiles // Prealloc list if possible. if n := len(baseTabels) + len(scratch.added) - len(scratch.deleted); n > 0 { @@ -480,6 +490,41 @@ func (p *versionStaging) finish() *version { nt = append(nt, t) } + // Avoid resort if only files in this level are deleted + if len(scratch.added) == 0 { + nv.levels[level] = nt + continue + } + + // For normal table compaction, one compaction will only involve two levels + // of files. And the new files generated after merging the source level and + // source+1 level related files can be inserted as a whole into source+1 level + // without any overlap with the other source+1 files. + // + // When the amount of data maintained by leveldb is large, the number of files + // per level will be very large. While qsort is very inefficient for sorting + // already ordered arrays. Therefore, for the normal table compaction, we use + // binary search here to find the insert index to insert a batch of new added + // files directly instead of using qsort. + if trivial && len(scratch.added) > 0 { + added := make(tFiles, 0, len(scratch.added)) + for _, r := range scratch.added { + added = append(added, tableFileFromRecord(r)) + } + if level == 0 { + added.sortByNum() + index := nt.searchNumLess(added[len(added)-1].fd.Num) + nt = append(nt[:index], append(added, nt[index:]...)...) + } else { + added.sortByKey(p.base.s.icmp) + _, amax := added.getRange(p.base.s.icmp) + index := nt.searchMin(p.base.s.icmp, amax) + nt = append(nt[:index], append(added, nt[index:]...)...) + } + nv.levels[level] = nt + continue + } + // New tables. for _, r := range scratch.added { nt = append(nt, tableFileFromRecord(r)) |