Add inline bucket support.

This commit adds support for writing small buckets directly inline to their value in
their parent's leaf node. Previously, subbuckets would simply have a bucket header
stored in their parent bucket which pointed to the root page. This required that
every bucket use at least a single page. This has a high overhead for buckets with
only one or two small items.

Inline buckets checks subbuckets to see if they only have a small amount of data
(about 1kb) and no subbuckets. If these conditions are met then the bucket's root
node is written to a fake page which is simply a pointer to the end of the bucket's
header.

Fixes #124.

1 files changed, 2 insertions, 8 deletions

diff --git a/db_test.go b/db_test.go
index b7e2a2f..903f65e 100644
--- a/db_test.go
+++ b/db_test.go
@@ -275,7 +275,7 @@ func TestDB_Stats(t *testing.T) {
 			return err
 		})
 		stats := db.Stats()
-		assert.Equal(t, 3, stats.TxStats.PageCount)
+		assert.Equal(t, 2, stats.TxStats.PageCount)
 	})
 }
 
@@ -324,13 +324,7 @@ func TestDB_Consistency(t *testing.T) {
 			if p, _ := tx.Page(5); assert.NotNil(t, p) {
 				assert.Equal(t, "leaf", p.Type) // root leaf
 			}
-			if p, _ := tx.Page(6); assert.NotNil(t, p) {
-				assert.Equal(t, "leaf", p.Type)
-			}
-			if p, _ := tx.Page(7); assert.NotNil(t, p) {
-				assert.Equal(t, "free", p.Type)
-			}
-			p, _ := tx.Page(8)
+			p, _ := tx.Page(6)
 			assert.Nil(t, p)
 			return nil
 		})