remove merge folder after merge completes (#26 )

Use consistent directory names in benchmarks (#24 )
* patch: use current directory for benchmarks * Use consistent directory names
2026-04-02 11:09:01 -07:00 · 2019-07-25 08:31:44 +10:00 · 2019-07-25 08:18:41 +10:00 · 2019-07-25 08:09:04 +10:00 · 2019-07-25 08:02:00 +10:00 · 2019-07-25 08:01:12 +10:00
16 changed files with 579 additions and 145 deletions
--- a/.drone.yml
+++ b/.drone.yml
@@ -5,7 +5,7 @@ steps:
  - name: build
    image: golang:latest
    commands:
-      - go test -v -short -cover -coverprofile=coverage.txt -coverpkg=$(go list) ./...
+      - go test -v -short -cover -coverprofile=coverage.txt -coverpkg=$(go list) .

  - name: coverage
    image: plugins/codecov
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -0,0 +1,8 @@
+# Contributing
+
+No preference. If you know hot to use Github and contributed to open source projects before then:
+
+* File an issue
+* Submit a pull request
+* File an issue + Submit a pull request
+* Use this project somewhere :)
--- a/14
+++ b/14
@@ -0,0 +1,14 @@
+# Build
+FROM prologic/go-builder:latest AS build
+
+# Runtime
+FROM alpine
+
+COPY --from=build /src/bitcaskd /bitcaskd
+
+EXPOSE 6379/tcp
+
+VOLUME /data
+
+ENTRYPOINT ["/bitcaskd"]
+CMD ["/data"]
--- a/10
+++ b/10
@@ -34,13 +34,17 @@ release:
 	@./tools/release.sh

 profile: build
-	@go test -cpuprofile cpu.prof -memprofile mem.prof -v -bench ./...
+	@go test -cpuprofile cpu.prof -memprofile mem.prof -v -bench .

 bench: build
-	@go test -v -benchmem -bench=. ./...
+	@go test -v -benchmem -bench=. .

 test: build
-	@go test -v -cover -coverprofile=coverage.txt -covermode=atomic -coverpkg=$(shell go list) -race ./...
+	@go test -v \
+		-cover -coverprofile=coverage.txt -covermode=atomic \
+		-coverpkg=$(shell go list) \
+		-race \
+		.

 clean:
 	@git clean -f -d -X
--- a/README.md
+++ b/README.md
@@ -5,17 +5,48 @@
 [![Go Report Card](https://goreportcard.com/badge/prologic/bitcask)](https://goreportcard.com/report/prologic/bitcask)
 [![GoDoc](https://godoc.org/github.com/prologic/bitcask?status.svg)](https://godoc.org/github.com/prologic/bitcask) 
 [![Sourcegraph](https://sourcegraph.com/github.com/prologic/bitcask/-/badge.svg)](https://sourcegraph.com/github.com/prologic/bitcask?badge)
+[![Github all releases](https://img.shields.io/github/downloads/prologic/bitcask/total.svg)](https://github.com/prologic/bitcask/releases)
+[![GitHub license](https://img.shields.io/github/license/prologic/bitcask.svg)](https://github.com/prologic/bitcask)

-A Bitcask (LSM+WAL) Key/Value Store written in Go.
+[![](https://images.microbadger.com/badges/version/prologic/bitcask.svg)](https://microbadger.com/images/prologic/bitcask)
+[![](https://images.microbadger.com/badges/image/prologic/bitcask.svg)](https://microbadger.com/images/prologic/bitcask)
+
+A high performance Key/Value store written in [Go](https://golang.org) with a predictable read/write performance and high throughput. Uses a [Bitcask](https://en.wikipedia.org/wiki/Bitcask) on-disk layout (LSM+WAL) similar to [Riak](https://riak.com/). 🗃️
+
+For a more feature-complete Redis-compatible server, distributed key/value store have a look at [Bitraft](https://github.com/prologic/bitraft) which uses this library as its backend. Use [Bitcask](https://github.com/prologic/bitcask) as a starting point or if you want to embed in your application, use [Bitraft](https://github.com/prologic/bitraft) if you need a complete server/client solution with high availability with a Redis-compatible API.

 ## Features

-* Embeddable
-* Builtin CLI
-* Builtin Redis-compatible server
+* Embeddable (`import "github.com/prologic/bitcask"`)
+* Builtin CLI (`bitcask`)
+* Builtin Redis-compatible server (`bitcaskd`)
 * Predictable read/write performance
 * Low latecny
-* High throughput (See: [Performance](README.md#Performance)
+* High throughput (See: [Performance](README.md#Performance) )
+
+## Development
+
+1. Get the source
+
+```#!bash
+$ git clone https://github.com/prologic/bitcask.git
+```
+
+2. Install required tools
+
+This library uses [Protobuf](https://github.com/protocolbuffers/protobuf) to serialize data on disk. Please follow the
+instructions for installing `protobuf` on your system. You will also need the
+following Go libraries/tools to generate Go code from Protobuf defs:
+
+3. Build the project
+
+```#!bash
+$ make
+```
+
+This will invoke `go generate` and `go build`.
+
+- [protoc-gen-go](https://github.com/golang/protobuf)

 ## Install

@@ -34,16 +65,13 @@ $ go get github.com/prologic/bitcask
 ```#!go
 package main

-import (
-    "log"
-
-    "github.com/prologic/bitcask"
-)
+import "github.com/prologic/bitcask"

 func main() {
    db, _ := bitcask.Open("/tmp/db")
-    db.Set("Hello", []byte("World"))
-    db.Close()
+    defer db.Close()
+    db.Put("Hello", []byte("World"))
+    val, _ := db.Get("Hello")
 }
 ```

@@ -90,6 +118,15 @@ QUIT
 Connection closed by foreign host.
 ```

+## Docker
+
+You can also use the [Bitcask Docker Image](https://cloud.docker.com/u/prologic/repository/docker/prologic/bitcask):
+
+```#!bash
+$ docker pull prologic/bitcask
+$ docker run -d -p 6379:6379 prologic/bitcask
+```
+
 ## Performance

 Benchmarks run on a 11" Macbook with a 1.4Ghz Intel Core i7:
@@ -97,32 +134,32 @@ Benchmarks run on a 11" Macbook with a 1.4Ghz Intel Core i7:
 ```
 $ make bench
 ...
-BenchmarkGet/128B-4         	  300000	      5178 ns/op	     400 B/op	       5 allocs/op
-BenchmarkGet/256B-4         	  300000	      5273 ns/op	     656 B/op	       5 allocs/op
-BenchmarkGet/512B-4         	  200000	      5368 ns/op	    1200 B/op	       5 allocs/op
-BenchmarkGet/1K-4           	  200000	      5800 ns/op	    2288 B/op	       5 allocs/op
-BenchmarkGet/2K-4           	  200000	      6766 ns/op	    4464 B/op	       5 allocs/op
-BenchmarkGet/4K-4           	  200000	      7857 ns/op	    9072 B/op	       5 allocs/op
-BenchmarkGet/8K-4           	  200000	      9538 ns/op	   17776 B/op	       5 allocs/op
-BenchmarkGet/16K-4          	  100000	     13188 ns/op	   34928 B/op	       5 allocs/op
-BenchmarkGet/32K-4          	  100000	     21620 ns/op	   73840 B/op	       5 allocs/op
+BenchmarkGet/128B-4         	  500000	      2537 ns/op	     672 B/op	       7 allocs/op
+BenchmarkGet/256B-4         	  500000	      2629 ns/op	    1056 B/op	       7 allocs/op
+BenchmarkGet/512B-4         	  500000	      2773 ns/op	    1888 B/op	       7 allocs/op
+BenchmarkGet/1K-4           	  500000	      3202 ns/op	    3552 B/op	       7 allocs/op
+BenchmarkGet/2K-4           	  300000	      3904 ns/op	    6880 B/op	       7 allocs/op
+BenchmarkGet/4K-4           	  300000	      5678 ns/op	   14048 B/op	       7 allocs/op
+BenchmarkGet/8K-4           	  200000	      8948 ns/op	   27360 B/op	       7 allocs/op
+BenchmarkGet/16K-4          	  100000	     14635 ns/op	   53472 B/op	       7 allocs/op
+BenchmarkGet/32K-4          	   50000	     28292 ns/op	  114912 B/op	       7 allocs/op

-BenchmarkPut/128B-4         	  200000	      7875 ns/op	     409 B/op	       6 allocs/op
-BenchmarkPut/256B-4         	  200000	      8712 ns/op	     538 B/op	       6 allocs/op
-BenchmarkPut/512B-4         	  200000	      9832 ns/op	     829 B/op	       6 allocs/op
-BenchmarkPut/1K-4           	  100000	     13105 ns/op	    1410 B/op	       6 allocs/op
-BenchmarkPut/2K-4           	  100000	     18601 ns/op	    2572 B/op	       6 allocs/op
-BenchmarkPut/4K-4           	   50000	     36631 ns/op	    5151 B/op	       6 allocs/op
-BenchmarkPut/8K-4           	   30000	     56128 ns/op	    9798 B/op	       6 allocs/op
-BenchmarkPut/16K-4          	   20000	     83209 ns/op	   18834 B/op	       6 allocs/op
-BenchmarkPut/32K-4          	   10000	    135899 ns/op	   41517 B/op	       6 allocs/op
+BenchmarkPut/128B-4         	  200000	      8173 ns/op	     409 B/op	       6 allocs/op
+BenchmarkPut/256B-4         	  200000	      8404 ns/op	     538 B/op	       6 allocs/op
+BenchmarkPut/512B-4         	  200000	      9741 ns/op	     829 B/op	       6 allocs/op
+BenchmarkPut/1K-4           	  100000	     13118 ns/op	    1411 B/op	       6 allocs/op
+BenchmarkPut/2K-4           	  100000	     17982 ns/op	    2573 B/op	       6 allocs/op
+BenchmarkPut/4K-4           	   50000	     35477 ns/op	    5154 B/op	       6 allocs/op
+BenchmarkPut/8K-4           	   30000	     54021 ns/op	    9804 B/op	       6 allocs/op
+BenchmarkPut/16K-4          	   20000	     96551 ns/op	   18849 B/op	       6 allocs/op
+BenchmarkPut/32K-4          	   10000	    129957 ns/op	   41561 B/op	       7 allocs/op

-BenchmarkScan-4             	 1000000	      1851 ns/op	     493 B/op	      25 allocs/op
+BenchmarkScan-4             	 1000000	      2011 ns/op	     493 B/op	      25 allocs/op
 ```

 For 128B values:

-* ~200,000 reads/sec
+* ~400,000 reads/sec
 * ~130,000 writes/sec

 The full benchmark above shows linear performance as you increase key/value sizes.
--- a/bitcask.go
+++ b/bitcask.go
@@ -8,6 +8,7 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"sync"

 	"github.com/gofrs/flock"
 	"github.com/prologic/trie"
@@ -16,14 +17,32 @@ import (
 )

 var (
-	ErrKeyNotFound    = errors.New("error: key not found")
-	ErrKeyTooLarge    = errors.New("error: key too large")
-	ErrValueTooLarge  = errors.New("error: value too large")
+	// ErrKeyNotFound is the error returned when a key is not found
+	ErrKeyNotFound = errors.New("error: key not found")
+
+	// ErrKeyTooLarge is the error returned for a key that exceeds the
+	// maximum allowed key size (configured with WithMaxKeySize).
+	ErrKeyTooLarge = errors.New("error: key too large")
+
+	// ErrValueTooLarge is the error returned for a value that exceeds the
+	// maximum allowed value size (configured with WithMaxValueSize).
+	ErrValueTooLarge = errors.New("error: value too large")
+
+	// ErrChecksumFailed is the error returned if a key/value retrieved does
+	// not match its CRC checksum
 	ErrChecksumFailed = errors.New("error: checksum failed")
+
+	// ErrDatabaseLocked is the error returned if the database is locked
+	// (typically opened by another process)
 	ErrDatabaseLocked = errors.New("error: database locked")
 )

+// Bitcask is a struct that represents a on-disk LSM and WAL data structure
+// and in-memory hash of key/value pairs as per the Bitcask paper and seen
+// in the Riak database.
 type Bitcask struct {
+	mu sync.RWMutex
+
 	*flock.Flock

 	config    *config
@@ -32,10 +51,11 @@ type Bitcask struct {
 	keydir    *internal.Keydir
 	datafiles []*internal.Datafile
 	trie      *trie.Trie
-
-	maxDatafileSize int64
 }

+// Close closes the database and removes the lock. It is important to call
+// Close() as this is the only way to cleanup the lock held by the open
+// database.
 func (b *Bitcask) Close() error {
 	defer func() {
 		b.Flock.Unlock()
@@ -48,10 +68,13 @@ func (b *Bitcask) Close() error {
 	return b.curr.Close()
 }

+// Sync flushes all buffers to disk ensuring all data is written
 func (b *Bitcask) Sync() error {
 	return b.curr.Sync()
 }

+// Get retrieves the value of the given key. If the key is not found or an/I/O
+// error occurs a null byte slice is returned along with the error.
 func (b *Bitcask) Get(key string) ([]byte, error) {
 	var df *internal.Datafile

@@ -66,7 +89,7 @@ func (b *Bitcask) Get(key string) ([]byte, error) {
 		df = b.datafiles[item.FileID]
 	}

-	e, err := df.ReadAt(item.Offset)
+	e, err := df.ReadAt(item.Offset, item.Size)
 	if err != nil {
 		return nil, err
 	}
@@ -79,27 +102,36 @@ func (b *Bitcask) Get(key string) ([]byte, error) {
 	return e.Value, nil
 }

+// Has returns true if the key exists in the database, false otherwise.
+func (b *Bitcask) Has(key string) bool {
+	_, ok := b.keydir.Get(key)
+	return ok
+}
+
+// Put stores the key and value in the database.
 func (b *Bitcask) Put(key string, value []byte) error {
-	if len(key) > b.config.MaxKeySize {
+	if len(key) > b.config.maxKeySize {
 		return ErrKeyTooLarge
 	}
-	if len(value) > b.config.MaxValueSize {
+	if len(value) > b.config.maxValueSize {
 		return ErrValueTooLarge
 	}

-	offset, err := b.put(key, value)
+	offset, n, err := b.put(key, value)
 	if err != nil {
 		return err
 	}

-	item := b.keydir.Add(key, b.curr.FileID(), offset)
+	item := b.keydir.Add(key, b.curr.FileID(), offset, n)
 	b.trie.Add(key, item)

 	return nil
 }

+// Delete deletes the named key. If the key doesn't exist or an I/O error
+// occurs the error is returned.
 func (b *Bitcask) Delete(key string) error {
-	_, err := b.put(key, []byte{})
+	_, _, err := b.put(key, []byte{})
 	if err != nil {
 		return err
 	}
@@ -110,6 +142,9 @@ func (b *Bitcask) Delete(key string) error {
 	return nil
 }

+// Scan performs a prefix scan of keys matching the given prefix and calling
+// the function `f` with the keys found. If the function returns an error
+// no further keys are processed and the first error returned.
 func (b *Bitcask) Scan(prefix string, f func(key string) error) error {
 	keys := b.trie.PrefixSearch(prefix)
 	for _, key := range keys {
@@ -120,6 +155,19 @@ func (b *Bitcask) Scan(prefix string, f func(key string) error) error {
 	return nil
 }

+// Len returns the total number of keys in the database
+func (b *Bitcask) Len() int {
+	return b.keydir.Len()
+}
+
+// Keys returns all keys in the database as a channel of string(s)
+func (b *Bitcask) Keys() chan string {
+	return b.keydir.Keys()
+}
+
+// Fold iterates over all keys in the database calling the function `f` for
+// each key. If the function returns an error, no further keys are processed
+// and the error returned.
 func (b *Bitcask) Fold(f func(key string) error) error {
 	for key := range b.keydir.Keys() {
 		if err := f(key); err != nil {
@@ -129,21 +177,20 @@ func (b *Bitcask) Fold(f func(key string) error) error {
 	return nil
 }

-func (b *Bitcask) put(key string, value []byte) (int64, error) {
-	size, err := b.curr.Size()
-	if err != nil {
-		return -1, err
-	}
+func (b *Bitcask) put(key string, value []byte) (int64, int64, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()

-	if size >= b.maxDatafileSize {
+	size := b.curr.Size()
+	if size >= int64(b.config.maxDatafileSize) {
 		err := b.curr.Close()
 		if err != nil {
-			return -1, err
+			return -1, 0, err
 		}

 		df, err := internal.NewDatafile(b.path, b.curr.FileID(), true)
 		if err != nil {
-			return -1, err
+			return -1, 0, err
 		}

 		b.datafiles = append(b.datafiles, df)
@@ -151,7 +198,7 @@ func (b *Bitcask) put(key string, value []byte) (int64, error) {
 		id := b.curr.FileID() + 1
 		curr, err := internal.NewDatafile(b.path, id, false)
 		if err != nil {
-			return -1, err
+			return -1, 0, err
 		}
 		b.curr = curr
 	}
@@ -160,11 +207,9 @@ func (b *Bitcask) put(key string, value []byte) (int64, error) {
 	return b.curr.Write(e)
 }

-func (b *Bitcask) setMaxDatafileSize(size int64) error {
-	b.maxDatafileSize = size
-	return nil
-}
-
+// Merge merges all datafiles in the database creating hint files for faster
+// startup. Old keys are squashed and deleted keys removes. Call this function
+// periodically to reclaim disk space.
 func Merge(path string, force bool) error {
 	fns, err := internal.GetDatafiles(path)
 	if err != nil {
@@ -185,10 +230,11 @@ func Merge(path string, force bool) error {
 	fns = fns[:len(fns)-1]
 	ids = ids[:len(ids)-1]

-	temp, err := ioutil.TempDir("", "bitcask")
+	temp, err := ioutil.TempDir(path, "merge")
 	if err != nil {
 		return err
 	}
+	defer os.RemoveAll(temp)

 	for i, fn := range fns {
 		// Don't merge Datafiles whose .hint files we've already generated
@@ -210,7 +256,7 @@ func Merge(path string, force bool) error {
 		defer df.Close()

 		for {
-			e, err := df.Read()
+			e, n, err := df.Read()
 			if err != nil {
 				if err == io.EOF {
 					break
@@ -224,7 +270,7 @@ func Merge(path string, force bool) error {
 				continue
 			}

-			keydir.Add(e.Key, ids[i], e.Offset)
+			keydir.Add(e.Key, ids[i], e.Offset, n)
 		}

 		tempdf, err := internal.NewDatafile(temp, id, false)
@@ -235,12 +281,12 @@ func Merge(path string, force bool) error {

 		for key := range keydir.Keys() {
 			item, _ := keydir.Get(key)
-			e, err := df.ReadAt(item.Offset)
+			e, err := df.ReadAt(item.Offset, item.Size)
 			if err != nil {
 				return err
 			}

-			_, err = tempdf.Write(e)
+			_, _, err = tempdf.Write(e)
 			if err != nil {
 				return err
 			}
@@ -271,7 +317,10 @@ func Merge(path string, force bool) error {
 	return nil
 }

-func Open(path string, options ...option) (*Bitcask, error) {
+// Open opens the database at the given path with optional options.
+// Options can be provided with the `WithXXX` functions that provide
+// configuration options as functions.
+func Open(path string, options ...Option) (*Bitcask, error) {
 	if err := os.MkdirAll(path, 0755); err != nil {
 		return nil, err
 	}
@@ -317,12 +366,12 @@ func Open(path string, options ...option) (*Bitcask, error) {

 			for key := range hint.Keys() {
 				item, _ := hint.Get(key)
-				_ = keydir.Add(key, item.FileID, item.Offset)
+				_ = keydir.Add(key, item.FileID, item.Offset, item.Size)
 				trie.Add(key, item)
 			}
 		} else {
 			for {
-				e, err := df.Read()
+				e, n, err := df.Read()
 				if err != nil {
 					if err == io.EOF {
 						break
@@ -336,7 +385,7 @@ func Open(path string, options ...option) (*Bitcask, error) {
 					continue
 				}

-				item := keydir.Add(e.Key, ids[i], e.Offset)
+				item := keydir.Add(e.Key, ids[i], e.Offset, n)
 				trie.Add(e.Key, item)
 			}
 		}
@@ -360,8 +409,6 @@ func Open(path string, options ...option) (*Bitcask, error) {
 		keydir:    keydir,
 		datafiles: datafiles,
 		trie:      trie,
-
-		maxDatafileSize: DefaultMaxDatafileSize,
 	}

 	for _, opt := range options {
--- a/bitcask_test.go
+++ b/bitcask_test.go
@@ -3,6 +3,7 @@ package bitcask
 import (
 	"fmt"
 	"io/ioutil"
+	"os"
 	"reflect"
 	"sort"
 	"strings"
@@ -40,6 +41,42 @@ func TestAll(t *testing.T) {
 		assert.Equal([]byte("bar"), val)
 	})

+	t.Run("Len", func(t *testing.T) {
+		assert.Equal(1, db.Len())
+	})
+
+	t.Run("Has", func(t *testing.T) {
+		assert.True(db.Has("foo"))
+	})
+
+	t.Run("Keys", func(t *testing.T) {
+		keys := make([]string, 0)
+		for key := range db.Keys() {
+			keys = append(keys, key)
+		}
+		assert.Equal([]string{"foo"}, keys)
+	})
+
+	t.Run("Fold", func(t *testing.T) {
+		var (
+			keys   []string
+			values [][]byte
+		)
+
+		err := db.Fold(func(key string) error {
+			value, err := db.Get(key)
+			if err != nil {
+				return err
+			}
+			keys = append(keys, key)
+			values = append(values, value)
+			return nil
+		})
+		assert.NoError(err)
+		assert.Equal([]string{"foo"}, keys)
+		assert.Equal([][]byte{[]byte("bar")}, values)
+	})
+
 	t.Run("Delete", func(t *testing.T) {
 		err := db.Delete("foo")
 		assert.NoError(err)
@@ -174,7 +211,7 @@ func TestMaxValueSize(t *testing.T) {
 	})
 }

-func TestMerge(t *testing.T) {
+func TestOpenMerge(t *testing.T) {
 	assert := assert.New(t)

 	testdir, err := ioutil.TempDir("", "bitcask")
@@ -187,7 +224,7 @@ func TestMerge(t *testing.T) {
 		)

 		t.Run("Open", func(t *testing.T) {
-			db, err = Open(testdir, WithMaxDatafileSize(1024))
+			db, err = Open(testdir, WithMaxDatafileSize(32))
 			assert.NoError(err)
 		})

@@ -245,6 +282,77 @@ func TestMerge(t *testing.T) {
 	})
 }

+func TestMergeOpen(t *testing.T) {
+	var (
+		db  *Bitcask
+		err error
+	)
+
+	assert := assert.New(t)
+
+	testdir, err := ioutil.TempDir("", "bitcask")
+	assert.NoError(err)
+
+	t.Run("Setup", func(t *testing.T) {
+		t.Run("Open", func(t *testing.T) {
+			db, err = Open(testdir, WithMaxDatafileSize(32))
+			assert.NoError(err)
+		})
+
+		t.Run("Put", func(t *testing.T) {
+			for i := 0; i < 1024; i++ {
+				err = db.Put(string(i), []byte(strings.Repeat(" ", 1024)))
+				assert.NoError(err)
+			}
+		})
+
+		t.Run("Get", func(t *testing.T) {
+			for i := 0; i < 32; i++ {
+				err = db.Put(string(i), []byte(strings.Repeat(" ", 1024)))
+				assert.NoError(err)
+				val, err := db.Get(string(i))
+				assert.NoError(err)
+				assert.Equal([]byte(strings.Repeat(" ", 1024)), val)
+			}
+		})
+
+		t.Run("Sync", func(t *testing.T) {
+			err = db.Sync()
+			assert.NoError(err)
+		})
+
+		t.Run("Close", func(t *testing.T) {
+			err = db.Close()
+			assert.NoError(err)
+		})
+	})
+
+	t.Run("Merge", func(t *testing.T) {
+		t.Run("Merge", func(t *testing.T) {
+			err = Merge(testdir, true)
+			assert.NoError(err)
+		})
+
+		t.Run("Open", func(t *testing.T) {
+			db, err = Open(testdir)
+			assert.NoError(err)
+		})
+
+		t.Run("Get", func(t *testing.T) {
+			for i := 0; i < 32; i++ {
+				val, err := db.Get(string(i))
+				assert.NoError(err)
+				assert.Equal([]byte(strings.Repeat(" ", 1024)), val)
+			}
+		})
+
+		t.Run("Close", func(t *testing.T) {
+			err = db.Close()
+			assert.NoError(err)
+		})
+	})
+}
+
 func TestConcurrent(t *testing.T) {
 	var (
 		db  *Bitcask
@@ -396,11 +504,17 @@ type benchmarkTestCase struct {
 }

 func BenchmarkGet(b *testing.B) {
-	testdir, err := ioutil.TempDir("", "bitcask")
+	currentDir, err := os.Getwd()
 	if err != nil {
 		b.Fatal(err)
 	}

+	testdir, err := ioutil.TempDir(currentDir, "bitcask_bench")
+	if err != nil {
+		b.Fatal(err)
+	}
+	defer os.RemoveAll(testdir)
+
 	db, err := Open(testdir)
 	if err != nil {
 		b.Fatal(err)
@@ -421,6 +535,8 @@ func BenchmarkGet(b *testing.B) {

 	for _, tt := range tests {
 		b.Run(tt.name, func(b *testing.B) {
+			b.SetBytes(int64(tt.size))
+
 			key := "foo"
 			value := []byte(strings.Repeat(" ", tt.size))

@@ -444,11 +560,17 @@ func BenchmarkGet(b *testing.B) {
 }

 func BenchmarkPut(b *testing.B) {
-	testdir, err := ioutil.TempDir("", "bitcask")
+	currentDir, err := os.Getwd()
 	if err != nil {
 		b.Fatal(err)
 	}

+	testdir, err := ioutil.TempDir(currentDir, "bitcask_bench")
+	if err != nil {
+		b.Fatal(err)
+	}
+	defer os.RemoveAll(testdir)
+
 	db, err := Open(testdir)
 	if err != nil {
 		b.Fatal(err)
@@ -469,6 +591,8 @@ func BenchmarkPut(b *testing.B) {

 	for _, tt := range tests {
 		b.Run(tt.name, func(b *testing.B) {
+			b.SetBytes(int64(tt.size))
+
 			key := "foo"
 			value := []byte(strings.Repeat(" ", tt.size))
 			b.ResetTimer()
@@ -483,11 +607,17 @@ func BenchmarkPut(b *testing.B) {
 }

 func BenchmarkScan(b *testing.B) {
-	testdir, err := ioutil.TempDir("", "bitcask")
+	currentDir, err := os.Getwd()
 	if err != nil {
 		b.Fatal(err)
 	}

+	testdir, err := ioutil.TempDir(currentDir, "bitcask_bench")
+	if err != nil {
+		b.Fatal(err)
+	}
+	defer os.RemoveAll(testdir)
+
 	db, err := Open(testdir)
 	if err != nil {
 		b.Fatal(err)
@@ -519,6 +649,9 @@ func BenchmarkScan(b *testing.B) {
 			keys = append(keys, key)
 			return nil
 		})
+		if err != nil {
+			b.Fatal(err)
+		}
 		sort.Strings(keys)
 		if !reflect.DeepEqual(expected, keys) {
 			b.Fatal(fmt.Errorf("expected keys=#%v got=%#v", expected, keys))
--- a/cmd/bitcaskd/main.go
+++ b/cmd/bitcaskd/main.go
@@ -96,6 +96,22 @@ func main() {
 				} else {
 					conn.WriteBulk(value)
 				}
+			case "keys":
+				conn.WriteArray(db.Len())
+				for key := range db.Keys() {
+					conn.WriteBulk([]byte(key))
+				}
+			case "exists":
+				if len(cmd.Args) != 2 {
+					conn.WriteError("ERR wrong number of arguments for '" + string(cmd.Args[0]) + "' command")
+					return
+				}
+				key := string(cmd.Args[1])
+				if db.Has(key) {
+					conn.WriteInt(1)
+				} else {
+					conn.WriteInt(0)
+				}
 			case "del":
 				if len(cmd.Args) != 2 {
 					conn.WriteError("ERR wrong number of arguments for '" + string(cmd.Args[0]) + "' command")
--- a/go.mod
+++ b/go.mod
@@ -1,18 +1,23 @@
 module github.com/prologic/bitcask

 require (
-	github.com/BurntSushi/toml v0.3.1 // indirect
 	github.com/gofrs/flock v0.7.1
 	github.com/gogo/protobuf v1.2.1
-	github.com/golang/protobuf v1.2.0
-	github.com/inconshreveable/mousetrap v1.0.0 // indirect
+	github.com/golang/protobuf v1.3.2
+	github.com/konsorten/go-windows-terminal-sequences v1.0.2 // indirect
+	github.com/magiconair/properties v1.8.1 // indirect
+	github.com/pelletier/go-toml v1.4.0 // indirect
 	github.com/pkg/errors v0.8.1
-	github.com/prologic/trie v0.0.0-20190316011403-395e39dac705
-	github.com/sirupsen/logrus v1.3.0
-	github.com/spf13/cobra v0.0.3
+	github.com/prologic/trie v0.0.0-20190322091023-3972df81f9b5
+	github.com/sirupsen/logrus v1.4.2
+	github.com/spf13/afero v1.2.2 // indirect
+	github.com/spf13/cobra v0.0.5
+	github.com/spf13/jwalterweatherman v1.1.0 // indirect
 	github.com/spf13/pflag v1.0.3
-	github.com/spf13/viper v1.3.1
+	github.com/spf13/viper v1.4.0
 	github.com/stretchr/testify v1.3.0
-	github.com/tidwall/redcon v0.9.0
-	golang.org/x/sync v0.0.0-20181108010431-42b317875d0f // indirect
+	github.com/tidwall/redcon v1.0.0
+	golang.org/x/exp v0.0.0-20190718202018-cfdd5522f6f6
+	golang.org/x/sys v0.0.0-20190712062909-fae7ac547cb7 // indirect
+	golang.org/x/text v0.3.2 // indirect
 )
--- a/go.sum
+++ b/go.sum
@@ -1,76 +1,198 @@
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+github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAElWljhcU=
+github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
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--- a/internal/datafile.go
+++ b/internal/datafile.go
@@ -1,12 +1,14 @@
 package internal

 import (
+	"bytes"
 	"fmt"
 	"os"
 	"path/filepath"
 	"sync"

 	"github.com/pkg/errors"
+	"golang.org/x/exp/mmap"

 	pb "github.com/prologic/bitcask/internal/proto"
 	"github.com/prologic/bitcask/internal/streampb"
@@ -17,7 +19,8 @@ const (
 )

 var (
-	ErrReadonly = errors.New("error: read only datafile")
+	ErrReadonly  = errors.New("error: read only datafile")
+	ErrReadError = errors.New("error: read error")
 )

 type Datafile struct {
@@ -25,6 +28,7 @@ type Datafile struct {

 	id     int
 	r      *os.File
+	ra     *mmap.ReaderAt
 	w      *os.File
 	offset int64
 	dec    *streampb.Decoder
@@ -34,6 +38,7 @@ type Datafile struct {
 func NewDatafile(path string, id int, readonly bool) (*Datafile, error) {
 	var (
 		r   *os.File
+		ra  *mmap.ReaderAt
 		w   *os.File
 		err error
 	)
@@ -56,6 +61,11 @@ func NewDatafile(path string, id int, readonly bool) (*Datafile, error) {
 		return nil, errors.Wrap(err, "error calling Stat()")
 	}

+	ra, err = mmap.Open(fn)
+	if err != nil {
+		return nil, err
+	}
+
 	offset := stat.Size()

 	dec := streampb.NewDecoder(r)
@@ -64,6 +74,7 @@ func NewDatafile(path string, id int, readonly bool) (*Datafile, error) {
 	return &Datafile{
 		id:     id,
 		r:      r,
+		ra:     ra,
 		w:      w,
 		offset: offset,
 		dec:    dec,
@@ -80,8 +91,14 @@ func (df *Datafile) Name() string {
 }

 func (df *Datafile) Close() error {
+	defer func() {
+		df.ra.Close()
+		df.r.Close()
+	}()
+
+	// Readonly Datafile -- Nothing further to close on the write side
 	if df.w == nil {
-		return df.r.Close()
+		return nil
 	}

 	err := df.Sync()
@@ -98,34 +115,51 @@ func (df *Datafile) Sync() error {
 	return df.w.Sync()
 }

-func (df *Datafile) Size() (int64, error) {
+func (df *Datafile) Size() int64 {
 	df.RLock()
 	defer df.RUnlock()
-	return df.offset, nil
+	return df.offset
 }

-func (df *Datafile) Read() (e pb.Entry, err error) {
+func (df *Datafile) Read() (e pb.Entry, n int64, err error) {
 	df.Lock()
 	defer df.Unlock()

-	return e, df.dec.Decode(&e)
-}
-
-func (df *Datafile) ReadAt(index int64) (e pb.Entry, err error) {
-	df.Lock()
-	defer df.Unlock()
-
-	_, err = df.r.Seek(index, os.SEEK_SET)
+	n, err = df.dec.Decode(&e)
 	if err != nil {
 		return
 	}

-	return e, df.dec.Decode(&e)
+	return
 }

-func (df *Datafile) Write(e pb.Entry) (int64, error) {
+func (df *Datafile) ReadAt(index, size int64) (e pb.Entry, err error) {
+	var n int
+
+	b := make([]byte, size)
+
 	if df.w == nil {
-		return -1, ErrReadonly
+		n, err = df.ra.ReadAt(b, index)
+	} else {
+		n, err = df.r.ReadAt(b, index)
+	}
+	if err != nil {
+		return
+	}
+	if int64(n) != size {
+		err = ErrReadError
+		return
+	}
+
+	buf := bytes.NewBuffer(b)
+	dec := streampb.NewDecoder(buf)
+	_, err = dec.Decode(&e)
+	return
+}
+
+func (df *Datafile) Write(e pb.Entry) (int64, int64, error) {
+	if df.w == nil {
+		return -1, 0, ErrReadonly
 	}

 	df.Lock()
@@ -135,9 +169,9 @@ func (df *Datafile) Write(e pb.Entry) (int64, error) {

 	n, err := df.enc.Encode(&e)
 	if err != nil {
-		return -1, err
+		return -1, 0, err
 	}
 	df.offset += n

-	return e.Offset, nil
+	return e.Offset, n, nil
 }
--- a/internal/keydir.go
+++ b/internal/keydir.go
@@ -11,6 +11,7 @@ import (
 type Item struct {
 	FileID int
 	Offset int64
+	Size   int64
 }

 type Keydir struct {
@@ -24,10 +25,11 @@ func NewKeydir() *Keydir {
 	}
 }

-func (k *Keydir) Add(key string, fileid int, offset int64) Item {
+func (k *Keydir) Add(key string, fileid int, offset, size int64) Item {
 	item := Item{
 		FileID: fileid,
 		Offset: offset,
+		Size:   size,
 	}

 	k.Lock()
@@ -52,11 +54,17 @@ func (k *Keydir) Delete(key string) {
 	delete(k.kv, key)
 }

+func (k *Keydir) Len() int {
+	return len(k.kv)
+}
+
 func (k *Keydir) Keys() chan string {
 	ch := make(chan string)
 	go func() {
-		for k := range k.kv {
-			ch <- k
+		k.RLock()
+		defer k.RUnlock()
+		for key := range k.kv {
+			ch <- key
 		}
 		close(ch)
 	}()
--- a/internal/proto/entry.pb.go
+++ b/internal/proto/entry.pb.go
@@ -32,7 +32,7 @@ func (m *Entry) Reset()         { *m = Entry{} }
 func (m *Entry) String() string { return proto.CompactTextString(m) }
 func (*Entry) ProtoMessage()    {}
 func (*Entry) Descriptor() ([]byte, []int) {
-	return fileDescriptor_entry_3e91842c99935ae2, []int{0}
+	return fileDescriptor_entry_db5b99f271e6b4b6, []int{0}
 }
 func (m *Entry) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Entry.Unmarshal(m, b)
@@ -84,9 +84,9 @@ func init() {
 	proto.RegisterType((*Entry)(nil), "proto.Entry")
 }

-func init() { proto.RegisterFile("entry.proto", fileDescriptor_entry_3e91842c99935ae2) }
+func init() { proto.RegisterFile("entry.proto", fileDescriptor_entry_db5b99f271e6b4b6) }

-var fileDescriptor_entry_3e91842c99935ae2 = []byte{
+var fileDescriptor_entry_db5b99f271e6b4b6 = []byte{
 	// 126 bytes of a gzipped FileDescriptorProto
 	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0xe2, 0x4e, 0xcd, 0x2b, 0x29,
 	0xaa, 0xd4, 0x2b, 0x28, 0xca, 0x2f, 0xc9, 0x17, 0x62, 0x05, 0x53, 0x4a, 0xc9, 0x5c, 0xac, 0xae,
--- a/internal/streampb/stream.go
+++ b/internal/streampb/stream.go
@@ -66,12 +66,12 @@ type Decoder struct {

 // Decode takes a proto.Message and unmarshals the next payload in the
 // underlying io.Reader. It returns an EOF when it's done.
-func (d *Decoder) Decode(v proto.Message) error {
+func (d *Decoder) Decode(v proto.Message) (int64, error) {
 	prefixBuf := make([]byte, prefixSize)

 	_, err := io.ReadFull(d.r, prefixBuf)
 	if err != nil {
-		return err
+		return 0, err
 	}

 	n := binary.BigEndian.Uint64(prefixBuf)
@@ -82,11 +82,11 @@ func (d *Decoder) Decode(v proto.Message) error {
 	for idx < n {
 		m, err := d.r.Read(buf[idx:n])
 		if err != nil {
-			return errors.Wrap(translateError(err), "failed reading marshaled data")
+			return 0, errors.Wrap(translateError(err), "failed reading marshaled data")
 		}
 		idx += uint64(m)
 	}
-	return proto.Unmarshal(buf[:n], v)
+	return int64(idx + prefixSize), proto.Unmarshal(buf[:n], v)
 }

 func translateError(err error) error {
--- a/options.go
+++ b/options.go
@@ -1,47 +1,53 @@
 package bitcask

 const (
+	// DefaultMaxDatafileSize is the default maximum datafile size in bytes
 	DefaultMaxDatafileSize = 1 << 20 // 1MB
-	DefaultMaxKeySize      = 64      // 64 bytes
-	DefaultMaxValueSize    = 1 << 16 // 65KB
+
+	// DefaultMaxKeySize is the default maximum key size in bytes
+	DefaultMaxKeySize = 64 // 64 bytes
+
+	// DefaultMaxValueSize is the default value size in bytes
+	DefaultMaxValueSize = 1 << 16 // 65KB
 )

-// Option ...
-type Option option
-
-type option func(*config) error
+// Option is a function that takes a config struct and modifies it
+type Option func(*config) error

 type config struct {
-	MaxDatafileSize int
-	MaxKeySize      int
-	MaxValueSize    int
+	maxDatafileSize int
+	maxKeySize      int
+	maxValueSize    int
 }

 func newDefaultConfig() *config {
 	return &config{
-		MaxDatafileSize: DefaultMaxDatafileSize,
-		MaxKeySize:      DefaultMaxKeySize,
-		MaxValueSize:    DefaultMaxValueSize,
+		maxDatafileSize: DefaultMaxDatafileSize,
+		maxKeySize:      DefaultMaxKeySize,
+		maxValueSize:    DefaultMaxValueSize,
 	}
 }

-func WithMaxDatafileSize(size int) option {
+// WithMaxDatafileSize sets the maximum datafile size option
+func WithMaxDatafileSize(size int) Option {
 	return func(cfg *config) error {
-		cfg.MaxDatafileSize = size
+		cfg.maxDatafileSize = size
 		return nil
 	}
 }

-func WithMaxKeySize(size int) option {
+// WithMaxKeySize sets the maximum key size option
+func WithMaxKeySize(size int) Option {
 	return func(cfg *config) error {
-		cfg.MaxKeySize = size
+		cfg.maxKeySize = size
 		return nil
 	}
 }

-func WithMaxValueSize(size int) option {
+// WithMaxValueSize sets the maximum value size option
+func WithMaxValueSize(size int) Option {
 	return func(cfg *config) error {
-		cfg.MaxValueSize = size
+		cfg.maxValueSize = size
 		return nil
 	}
 }
--- a/tools/release.sh
+++ b/tools/release.sh
@@ -20,6 +20,6 @@ fi

 echo "Releasing ${TAG} ..."

-git tag -a -s -m "Relase ${TAG}" "${TAG}"
+git tag -a -s -m "Release ${TAG}" "${TAG}"
 git push --tags
 goreleaser release --rm-dist
Author	SHA1	Message	Date
Awn	b7ac95d66a	remove merge folder after merge completes (#26 )	2019-07-25 08:31:44 +10:00
Awn	c28c72108f	Use consistent directory names in benchmarks (#24 ) * patch: use current directory for benchmarks * Use consistent directory names	2019-07-25 08:18:41 +10:00
Awn	a74203b99e	patch: use current directory for benchmarks (#23 )	2019-07-25 08:09:04 +10:00
Awn	5ee0f8e0df	update dependencies (#22 )	2019-07-25 08:02:00 +10:00
Awn	479cabcc8e	patch: use directory within database path for merge (#21 )	2019-07-25 08:01:12 +10:00
Awn	3b63388e79	benchmarks: set test size to compute throughput (#16 ) * benchmarks: set test size to compute throughput * patch: error on cross-filesystem rename operation * revert: commit to wrong branch	2019-07-25 07:14:58 +10:00
panyun	fd2023ee38	Fix issue(db file Merge issue in windows env): (#15 ) * Fix issue(windows env): 1. Run my program firstly, it will create my.db folder normaly. 2. Close my program and restart it again, I will receive an error. * Fix coding format issue * Change the last fixing with @prologic suggestion.	2019-07-23 13:27:14 +10:00
James Mills	47ad6601f3	Update generated protobuf code	2019-07-19 20:49:49 +10:00
Christian Muehlhaeuser	057c147f89	Added missing error check (#13 ) err was assigned, but not checked.	2019-07-19 20:22:56 +10:00
Jesse Donat	9fafcad9a6	Fix mismatched key casing. (#12 )	2019-06-12 07:29:11 +10:00
Whemoon Jang	c4faac9f7c	Fix outdated README (#11 )	2019-06-03 20:48:30 +10:00
Yury Fedorov	43334647a6	Fix typos in bitcask.go docs (#10 )	2019-05-26 19:27:03 +10:00
Christian Muehlhaeuser	f26a1b1727	Fixed typo in release.sh (#8 )	2019-04-25 22:19:20 +10:00
Kebert Xela	1fca55d268	Minor readme improvements (#7 ) * File emoji and missing parenthesis * Update README.md * Update README.md	2019-04-24 06:44:21 +10:00
James Mills	c640f7f7e7	Update README.md	2019-04-01 17:36:18 +10:00
James Mills	b6c9867e7b	Added missing dependency on github.com/golang/protobuf/proto Fixes #6	2019-04-01 17:29:23 +10:00
James Mills	ed6283dca4	Add Development section to README documenting use of Protobuf and tooling required. #6	2019-04-01 17:29:23 +10:00
James Mills	f44b6249ac	Create CONTRIBUTING.md	2019-04-01 10:14:40 +10:00
James Mills	2be3a63153	Add other badges from img.shields.io	2019-03-31 13:39:58 +10:00
James Mills	836deeb0ff	Document using the Docker Image	2019-03-30 20:25:23 +10:00
James Mills	b29b4c5422	Add Dockerfile to publish images to Docker Hub	2019-03-30 17:14:09 +10:00
James Mills	f397a73abd	Update README.md	2019-03-29 22:21:39 +10:00
James Mills	53dc013215	Optimized and increased read performance by ~2-3x by memory mapping the read-only datafiles	2019-03-23 13:35:55 +10:00
James Mills	711d08ce91	Increased read performance by ~3-4x by removing another unnecessary I/O operation (Seek)	2019-03-23 12:14:15 +10:00
James Mills	c3b1a02371	Updated deps	2019-03-22 21:53:09 +10:00
James Mills	7149cb9afe	Fixed concurrency bug with reopening datafiles when maxDatafileSize is exceeded	2019-03-22 17:59:07 +10:00
James Mills	c593bc966f	Refactor Datafile.Size()	2019-03-22 17:33:24 +10:00
James Mills	2400dd86d5	Add docs for bitcask	2019-03-21 17:46:53 +10:00
James Mills	27eb922ba2	Add docs for options	2019-03-21 17:20:53 +10:00
James Mills	34ad78efc0	Add KeYS command to server (bitraftd)	2019-03-21 10:49:53 +10:00
James Mills	352c32ee12	Add Len() to exported API (extended API)	2019-03-21 10:47:50 +10:00
James Mills	aaea7273c3	Add Keys() to exported API (extended API)	2019-03-21 10:41:56 +10:00
James Mills	01cb269a51	Add EXISTS command to server (bitraftd)	2019-03-21 10:29:18 +10:00
James Mills	962e53af17	Add Has() to exported API (extended API)	2019-03-21 10:24:48 +10:00
James Mills	7a427a237a	Update README.md	2019-03-21 08:36:17 +10:00
James Mills	8bf169c96f	Add MergeOpen test case	2019-03-20 17:10:24 +10:00
James Mills	c1488fed2a	Added Fold() test case	2019-03-20 16:55:59 +10:00
James Mills	d6e806e655	Update README.md	2019-03-20 15:30:08 +10:00