diff options
| -rw-r--r-- | db.go | 21 | ||||
| -rw-r--r-- | db_test.go | 41 |
2 files changed, 53 insertions, 9 deletions
@@ -12,9 +12,6 @@ import ( "unsafe" ) -// The smallest size that the mmap can be. -const minMmapSize = 1 << 22 // 4MB - // The largest step that can be taken when remapping the mmap. const maxMmapStep = 1 << 30 // 1GB @@ -222,15 +219,21 @@ func (db *DB) munmap() error { // mmapSize determines the appropriate size for the mmap given the current size // of the database. The minimum size is 4MB and doubles until it reaches 1GB. func (db *DB) mmapSize(size int) int { - if size <= minMmapSize { - return minMmapSize - } else if size < maxMmapStep { - size *= 2 - } else { - size += maxMmapStep + // Double the size from 1MB until 1GB. + for i := uint(20); i < 30; i++ { + if size <= 1<<i { + return 1 << i + } + } + + // If larger than 1GB then grow by 1GB at a time. + size += maxMmapStep + if remainder := size % maxMmapStep; remainder > 0 { + size -= remainder } // Ensure that the mmap size is a multiple of the page size. + // This should always be true since we're incrementing in MBs. if (size % db.pageSize) != 0 { size = ((size / db.pageSize) + 1) * db.pageSize } @@ -85,6 +85,39 @@ func TestOpen_Wait(t *testing.T) { assert(t, time.Since(start) > 100*time.Millisecond, "") } +// Ensure that opening a database does not increase its size. +// https://github.com/boltdb/bolt/issues/291 +func TestOpen_Size(t *testing.T) { + // Open a data file. + db := NewTestDB() + path := db.Path() + defer db.Close() + + // Insert until we get above the minimum 4MB size. + db.Update(func(tx *bolt.Tx) error { + b, _ := tx.CreateBucketIfNotExists([]byte("data")) + for i := 0; i < 10000; i++ { + _ = b.Put([]byte(fmt.Sprintf("%04d", i)), make([]byte, 1000)) + } + return nil + }) + + // Close database and grab the size. + db.DB.Close() + sz := fileSize(path) + + // Reopen database, update, and check size again. + db0, _ := bolt.Open(path, 0666, nil) + db0.Update(func(tx *bolt.Tx) error { return tx.Bucket([]byte("data")).Put([]byte{0}, []byte{0}) }) + db0.Close() + newSz := fileSize(path) + + // Compare the original size with the new size. + if sz != newSz { + t.Fatalf("unexpected file growth: %d => %d", sz, newSz) + } +} + // Ensure that a re-opened database is consistent. func TestOpen_Check(t *testing.T) { path := tempfile() @@ -648,3 +681,11 @@ func trunc(b []byte, length int) []byte { func truncDuration(d time.Duration) string { return regexp.MustCompile(`^(\d+)(\.\d+)`).ReplaceAllString(d.String(), "$1") } + +func fileSize(path string) int64 { + fi, err := os.Stat(path) + if err != nil { + return 0 + } + return fi.Size() +} |