[PATCH] build: Disable fsync around temporary checkouts

[Colin Walters <walters verbum org>]

When we're not commiting objects, there's no need to fsync the
directories to disk.  This is a fairly substantial speedup even here
on my SSD, I assume it'll be even better on less optimal storage.
---
 src/js/tasks/task-build.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/js/tasks/task-build.js b/src/js/tasks/task-build.js
index a5ca125..79f81ed 100644
--- a/src/js/tasks/task-build.js
+++ b/src/js/tasks/task-build.js
@@ -120,6 +120,7 @@ const TaskBuild = new Lang.Class({
        }));
 
        BuildUtil.timeSubtask("compose buildroot", Lang.bind(this,
        function () {
+           this.ostreeRepo.set_disable_fsync(true);
             trees.forEach(Lang.bind(this, function([root, commit,
             subpath]) {
                let subtree = root.resolve_relative_path(subpath);
                let subtreeInfo =
                subtree.query_info(OSTREE_GIO_FAST_QUERYINFO,
@@ -130,6 +131,7 @@ const TaskBuild = new Lang.Class({
                                               OSTree.RepoCheckoutOverwriteMode.UNION_FILES,
                                               cachedRootTmp, subtree,
                                               subtreeInfo,
                                               cancellable);
             }));
+           this.ostreeRepo.set_disable_fsync(false);
            this._runTriggersInRoot(cachedRootTmp, cancellable);
            let builddirTmp = cachedRootTmp.get_child('ostbuild');
            GSystem.file_ensure_directory(builddirTmp.resolve_relative_path('source/'
            + componentName), true, cancellable);
@@ -856,6 +858,7 @@ const TaskBuild = new Lang.Class({
        GSystem.shutil_rm_rf(composeRootdir, cancellable);
         GSystem.file_ensure_directory(composeRootdir, true,
         cancellable);
 
+       this.ostreeRepo.set_disable_fsync(true);
         composeContents.forEach(Lang.bind(this, function([branch,
         subpath]) {
             let [, root] = this.ostreeRepo.read_commit(branch,
             cancellable);
             let subtree = root.resolve_relative_path(subpath);
@@ -872,6 +875,7 @@ const TaskBuild = new Lang.Class({
                                           OSTree.RepoCheckoutOverwriteMode.UNION_FILES,
                                           composeRootdir, subtree,
                                           subtreeInfo, cancellable);
         }));
+       this.ostreeRepo.set_disable_fsync(false);
 
        if (params.runTriggers)
            this._runTriggersInRoot(composeRootdir, cancellable);
@@ -967,11 +971,13 @@ const TaskBuild = new Lang.Class({
        print("Preparing commit of " + composeRootdir.get_path() + " to
        " + targetName);
        let rev;
        BuildUtil.timeSubtask("compose " + targetName, Lang.bind(this,
        function() {
+           this.ostreeRepo.set_disable_fsync(false);
             this.ostreeRepo.prepare_transaction(cancellable);
             this.ostreeRepo.scan_hardlinks(cancellable);
             let file = this._writeMtreeFromDirectory(composeRootdir,
             [], cancellable);
             rev = this._commit(treename, "Compose", file, cancellable);
             this.ostreeRepo.commit_transaction(cancellable);
+           this.ostreeRepo.set_disable_fsync(true);
        }));
         print("Compose of " + targetName + " is " + rev);
 
-- 
1.8.3.1