Perf: Traverse commit history instead of reading the packfile

To avoid show orphan commits and improve performance on commits table, instead of read all the objects from each repository and discard commits, we can execute from go-git a git log --all command and traverse commit history, avoiding read a lot of data from disk.

Signed-off-by: Antonio Jesus Navarro Perez <[email protected]>

Author: ajnavarro

commits.go

@@ -3,6 +3,7 @@ package gitbase
 import (
 	"io"
 
+	git "gopkg.in/src-d/go-git.v4"
 	"gopkg.in/src-d/go-mysql-server.v0/sql"
 
 	"gopkg.in/src-d/go-git.v4/plumbing"
@@ -161,7 +162,10 @@ func (i *commitIter) init() error {
 	if len(i.hashes) > 0 {
 		i.iter, err = NewCommitsByHashIter(i.repo, i.hashes)
 	} else {
-		i.iter, err = i.repo.CommitObjects()
+		i.iter, err =
+			i.repo.Log(&git.LogOptions{
+				All: true,
+			})
 	}
 
 	return err
@@ -245,7 +249,10 @@ func NewCommitsByHashIter(
 	var commitIter object.CommitIter
 	var err error
 	if len(hashes) == 0 {
-		commitIter, err = repo.CommitObjects()
+		commitIter, err =
+			repo.Log(&git.LogOptions{
+				All: true,
+			})
 		if err != nil {
 			return nil, err
 		}
@@ -333,7 +340,10 @@ func newCommitsKeyValueIter(
 		return nil, err
 	}
 
-	commits, err := repo.CommitObjects()
+	commits, err :=
+		repo.Log(&git.LogOptions{
+			All: true,
+		})
 	if err != nil {
 		return nil, err
 	}