func create(f *os.File, filer lldb.Filer, opts *Options, isMem bool) (db *DB, err error) {
defer func() {
if db != nil {
db.opts = opts
}
}()
defer func() {
lock := opts.lock
if err != nil && lock != nil {
lock.Close()
db = nil
}
}()
if err = opts.check(filer.Name(), true, !isMem); err != nil {
return
}
b := [16]byte{byte(magic[0]), byte(magic[1]), byte(magic[2]), byte(magic[3]), 0x00} // ver 0x00
if n, err := filer.WriteAt(b[:], 0); n != 16 {
return nil, &os.PathError{Op: "kv.create.WriteAt", Path: filer.Name(), Err: err}
}
db = &DB{f: f, lock: opts.lock}
if filer, err = opts.acidFiler(db, filer); err != nil {
return nil, err
}
db.filer = filer
if err = filer.BeginUpdate(); err != nil {
return
}
defer func() {
if e := filer.EndUpdate(); e != nil {
if err == nil {
err = e
}
}
}()
if db.alloc, err = lldb.NewAllocator(lldb.NewInnerFiler(filer, 16), &lldb.Options{}); err != nil {
return nil, &os.PathError{Op: "kv.create", Path: filer.Name(), Err: err}
}
db.alloc.Compress = true
db.isMem = isMem
var h int64
if db.root, h, err = lldb.CreateBTree(db.alloc, opts.Compare); err != nil {
return
}
if h != 1 {
panic("internal error")
}
db.wal = opts.wal
return
}
func fillseq() {
dbname := os.Args[0] + ".db"
f, err := os.OpenFile(dbname, os.O_CREATE|os.O_EXCL|os.O_RDWR, 0666)
if err != nil {
log.Fatal(err)
}
defer func() {
f.Close()
os.Remove(f.Name())
}()
filer := lldb.NewSimpleFileFiler(f)
a, err := lldb.NewAllocator(filer, &lldb.Options{})
if err != nil {
log.Println(err)
return
}
a.Compress = true
b, _, err := lldb.CreateBTree(a, nil)
if err != nil {
log.Println(err)
return
}
var keys [N][16]byte
for i := range keys {
binary.BigEndian.PutUint32(keys[i][:], uint32(i))
}
debug.FreeOSMemory()
t0 := time.Now()
for _, key := range keys {
if err = b.Set(key[:], value100); err != nil {
log.Println(err)
return
}
}
if err := filer.Sync(); err != nil {
log.Println(err)
return
}
var ms runtime.MemStats
runtime.ReadMemStats(&ms)
d := time.Since(t0)
fi, err := f.Stat()
if err != nil {
log.Println(err)
return
}
secs := float64(d/time.Nanosecond) / float64(time.Second)
sz := fi.Size()
fmt.Printf("fillseq :%19v/op;%7.1f MB/s (%g secs, %d bytes)\n", d/N, float64(sz)/secs/1e6, secs, sz)
nn, bytes := bufs.GCache.Stats()
fmt.Printf("%d %d\n", nn, bytes)
fmt.Printf("%+v\n", ms)
}
func (t *treeCache) getTree(db *DB, prefix int, name string, canCreate bool, cacheSize int) (r *lldb.BTree, err error) {
m := t.get()
r, ok := m[name]
if ok {
return
}
root, err := db.root()
if err != nil {
return
}
val, err := root.get(prefix, name)
if err != nil {
return
}
switch x := val.(type) {
case nil:
if !canCreate {
return
}
var h int64
r, h, err = lldb.CreateBTree(db.alloc, collate)
if err != nil {
return nil, err
}
if err = root.set(h, prefix, name); err != nil {
return nil, err
}
case int64:
if r, err = lldb.OpenBTree(db.alloc, collate, x); err != nil {
return nil, err
}
default:
return nil, &lldb.ErrINVAL{Src: "corrupted root directory value for", Val: fmt.Sprintf("%q, %q", prefix, name)}
}
if len(m) > cacheSize {
i, j, n := 0, cacheSize/2, mathutil.Min(cacheSize/20, 10)
loop:
for k := range m {
if i++; i >= j {
delete(m, k)
if n == 0 {
break loop
}
n--
}
}
}
m[name] = r
return
}
func TestProf(t *testing.T) {
dbname := os.Args[0] + ".db"
f, err := os.OpenFile(dbname, os.O_CREATE|os.O_EXCL|os.O_RDWR, 0666)
if err != nil {
t.Fatal(err)
}
defer func() {
f.Close()
os.Remove(f.Name())
}()
filer := lldb.NewSimpleFileFiler(f) // file
//filer := lldb.NewMemFiler() // mem
a, err := lldb.NewAllocator(filer, &lldb.Options{})
if err != nil {
t.Error(err)
return
}
a.Compress = true
b, _, err := lldb.CreateBTree(a, nil)
if err != nil {
t.Error(err)
return
}
var key [16]byte
for i := uint32(0); int(i) < 1e6; i++ {
binary.BigEndian.PutUint32(key[:], i)
if err = b.Set(key[:], value100); err != nil {
t.Error(err)
return
}
}
var ms runtime.MemStats
runtime.ReadMemStats(&ms)
bufsU, bufsT, bytesU, bytesT, h, m := a.CacheStats()
const p = 100.0
t.Logf(
"cache: buffers %d/%d(%.1f%%), bytes %d/%d(%.1f%%), hits %d(%.1f%%), misses %d(%.1f%%)",
bufsU, bufsT, p*float64(bufsU)/float64(bufsT),
bytesU, bytesT, p*float64(bytesU)/float64(bytesT),
h, p*float64(h)/float64(h+m),
m, p*float64(m)/float64(h+m),
)
nn, bts := bufs.GCache.Stats()
t.Logf("bufs.GCache.Stats() {%d, %d}", nn, bts)
t.Logf("%+v\n", ms)
}
func BenchmarkMem(b *testing.B) {
f, err := ioutil.TempFile("", "")
if err != nil {
b.Fatal(err)
}
defer func() {
f.Close()
os.Remove(f.Name())
}()
filer := lldb.NewSimpleFileFiler(f)
a, err := lldb.NewAllocator(filer, &lldb.Options{})
if err != nil {
b.Error(err)
return
}
a.Compress = true
t, _, err := lldb.CreateBTree(a, nil)
if err != nil {
b.Error(err)
return
}
b.ResetTimer()
var key [16]byte
for i := uint32(0); int(i) < b.N; i++ {
binary.BigEndian.PutUint32(key[:], i)
if err = t.Set(key[:], value100); err != nil {
b.Error(err)
return
}
}
if err := filer.Sync(); err != nil {
b.Error(err)
return
}
}
func (db *DB) root() (r *Array, err error) {
if r = db._root; r != nil {
return
}
sz, err := db.filer.Size()
if err != nil {
return
}
switch {
case sz < db.emptySize:
panic(fmt.Errorf("internal error: %d", sz))
case sz == db.emptySize:
tree, h, err := lldb.CreateBTree(db.alloc, collate)
if err != nil {
return nil, err
}
if h != 1 {
panic("internal error")
}
r = &Array{db, tree, nil, "", 0}
db._root = r
return r, nil
default:
tree, err := lldb.OpenBTree(db.alloc, collate, 1)
if err != nil {
return nil, err
}
r = &Array{db, tree, nil, "", 0}
db._root = r
return r, nil
}
}