Fix long commit history slowing summary page https://tangled.org/pocka.jp/legit/issues/7#comment-3mqn5xujwoh22 The summary page displays recent up to three commits, but underlying logic reads the whole repo history then subslice the result. The loading of entire commit history is really demanding task and slows the response time of a summary page down a lot. Before this patch, loading a summary page of Zig project took 900ms ~ 1100ms. After this patch, it's 180ms under load.

Changes

2 changed files (+32/-13)

• git/git.go
  • @@ -104,19 +104,42 @@ func Open(path string, ref string) (*GitRepo, error) {
    return &g, nil } - func (g *GitRepo) Commits() ([]*object.Commit, error) { + type CommitsOptions struct { + // Limit is maximum number of commits to retrieve. + // 0 means no limit. + Limit uint32 + } + + func (g *GitRepo) Commits(opts CommitsOptions) ([]*object.Commit, error) { ci, err := g.r.Log(&git.LogOptions{From: g.h}) if err != nil { return nil, fmt.Errorf("commits from ref: %w", err) } - commits := []*object.Commit{} - ci.ForEach(func(c *object.Commit) error { - commits = append(commits, c) - return nil - }) + if opts.Limit > 0 { + commits := make([]*object.Commit, 0, opts.Limit) - return commits, nil + for range opts.Limit { + if next, err := ci.Next(); err != nil { + if err != io.EOF { + return nil, fmt.Errorf("log failure: %w", err) + } + } else { + commits = append(commits, next) + } + } + + return commits, nil + } else { + commits := []*object.Commit{} + + ci.ForEach(func(c *object.Commit) error { + commits = append(commits, c) + return nil + }) + + return commits, nil + } } func (g *GitRepo) LastCommit() (*object.Commit, error) {
• routes/routes.go
  • @@ -116,7 +116,7 @@ func (d *deps) RepoIndex(w http.ResponseWriter, r *http.Request) {
    return } - commits, err := gr.Commits() + commits, err := gr.Commits(git.CommitsOptions{Limit: 3}) if err != nil { d.Write500(w) log.Println(err)
  • @@ -159,10 +159,6 @@ func (d *deps) RepoIndex(w http.ResponseWriter, r *http.Request) {
    } } - if len(commits) >= 3 { - commits = commits[:3] - } - data := repoTopData{ Config: d.c, Meta: repositoryMeta{
  • @@ -457,7 +453,7 @@ func (d *deps) Log(w http.ResponseWriter, r *http.Request) {
    return } - commits, err := gr.Commits() + commits, err := gr.Commits(git.CommitsOptions{}) if err != nil { d.Write500(w) log.Println(err)