From 27a45e2edbd1c4551b801a957cafcb27b3417fd3 Mon Sep 17 00:00:00 2001 From: Giuseppe Scrivano Date: Thu, 22 Jan 2015 01:05:13 +0100 Subject: [PATCH] pull: use a single per-transaction syncfs instead of fsync Do not write directly to objects/ but maintain pulled files under tmp/ with a "tmpobject-$CHECKSUM.$OBJTYPE" name until they are syncfs'ed to disk. Move them under objects/ at ostree_repo_commit_transaction cleanup time. Before (test done on a local network): $ LANG=C sudo time ./ostree --repo=repo pull origin master 0 metadata, 3 content objects fetched; 83820 KiB; 4 delta parts fetched, transferred in 417 seconds 16.42user 6.73system 6:57.19elapsed 5%CPU (0avgtext+0avgdata 248428maxresident)k 24inputs+794472outputs (0major+233968minor)pagefaults 0swaps After: $ LANG=C sudo time ./ostree --repo=repo pull origin master 0 metadata, 3 content objects fetched; 83820 KiB; 4 delta parts fetched, transferred in 9 seconds 14.70user 2.87system 0:09.99elapsed 175%CPU (0avgtext+0avgdata 256168maxresident)k 0inputs+794472outputs (0major+164333minor)pagefaults 0swaps https://bugzilla.gnome.org/show_bug.cgi?id=728065 Signed-off-by: Giuseppe Scrivano --- src/libostree/ostree-repo-commit.c | 148 ++++++++++++++++++++++++---- src/libostree/ostree-repo-private.h | 8 ++ src/libostree/ostree-repo.c | 81 ++++++++++----- 3 files changed, 197 insertions(+), 40 deletions(-) diff --git a/src/libostree/ostree-repo-commit.c b/src/libostree/ostree-repo-commit.c index a149c2e0..c6ac5728 100644 --- a/src/libostree/ostree-repo-commit.c +++ b/src/libostree/ostree-repo-commit.c @@ -35,6 +35,7 @@ #include "ostree-mutable-tree.h" #include "ostree-varint.h" #include +#include gboolean _ostree_repo_ensure_loose_objdir_at (int dfd, @@ -59,6 +60,19 @@ _ostree_repo_ensure_loose_objdir_at (int dfd, return TRUE; } +void +_ostree_repo_get_tmpobject_path (OstreeRepo *repo, + char *output, + const char *checksum, + OstreeObjectType objtype) +{ + g_sprintf (output, + "%s/tmpobject-%s.%s", + repo->boot_id, + checksum, + ostree_object_type_to_string (objtype)); +} + static GVariant * create_file_metadata (GFileInfo *file_info, GVariant *xattrs) @@ -108,6 +122,7 @@ write_file_metadata_to_xattr (int fd, static gboolean commit_loose_object_trusted (OstreeRepo *self, + const char *checksum, OstreeObjectType objtype, const char *loose_path, GFile *temp_file, @@ -251,7 +266,7 @@ commit_loose_object_trusted (OstreeRepo *self, /* Ensure that in case of a power cut, these files have the data we * want. See http://lwn.net/Articles/322823/ */ - if (!self->disable_fsync) + if (!self->in_transaction && !self->disable_fsync) { if (fsync (fd) == -1) { @@ -267,20 +282,39 @@ commit_loose_object_trusted (OstreeRepo *self, if (!_ostree_repo_ensure_loose_objdir_at (self->objects_dir_fd, loose_path, cancellable, error)) goto out; - - if (G_UNLIKELY (renameat (self->tmp_dir_fd, temp_filename, - self->objects_dir_fd, loose_path) == -1)) - { - if (errno != EEXIST) - { - gs_set_error_from_errno (error, errno); - g_prefix_error (error, "Storing file '%s': ", temp_filename); - goto out; - } - else - (void) unlinkat (self->tmp_dir_fd, temp_filename, 0); - } + { + gs_free gchar *tmp_dest = NULL; + int dir; + const char *dest; + + if (self->in_transaction) + { + char tmpbuf[_OSTREE_LOOSE_PATH_MAX]; + _ostree_repo_get_tmpobject_path (self, tmpbuf, checksum, objtype); + tmp_dest = g_strdup (tmpbuf); + dir = self->tmp_dir_fd; + dest = tmp_dest; + } + else + { + dir = self->objects_dir_fd; + dest = loose_path; + } + + if (G_UNLIKELY (renameat (self->tmp_dir_fd, temp_filename, + dir, dest) == -1)) + { + if (errno != EEXIST) + { + gs_set_error_from_errno (error, errno); + g_prefix_error (error, "Storing file '%s': ", temp_filename); + goto out; + } + else + (void) unlinkat (self->tmp_dir_fd, temp_filename, 0); + } + } ret = TRUE; out: return ret; @@ -474,7 +508,7 @@ write_object (OstreeRepo *self, { if (!_ostree_repo_has_loose_object (self, expected_checksum, objtype, &have_obj, loose_objpath, - cancellable, error)) + NULL, cancellable, error)) goto out; if (have_obj) { @@ -655,7 +689,7 @@ write_object (OstreeRepo *self, } if (!_ostree_repo_has_loose_object (self, actual_checksum, objtype, - &have_obj, loose_objpath, + &have_obj, loose_objpath, NULL, cancellable, error)) goto out; @@ -663,7 +697,8 @@ write_object (OstreeRepo *self, if (do_commit) { - if (!commit_loose_object_trusted (self, objtype, loose_objpath, + if (!commit_loose_object_trusted (self, actual_checksum, + objtype, loose_objpath, temp_file, temp_filename, object_is_symlink, file_info, xattrs, temp_out, @@ -930,6 +965,17 @@ ostree_repo_prepare_transaction (OstreeRepo *self, if (!ot_gfile_ensure_unlinked (self->transaction_lock_path, cancellable, error)) goto out; } + + if (mkdirat (self->tmp_dir_fd, self->boot_id, 0777) == -1) + { + int errsv = errno; + if (G_UNLIKELY (errsv != EEXIST)) + { + gs_set_error_from_errno (error, errsv); + goto out; + } + } + transaction_str = g_strdup_printf ("pid=%llu", (unsigned long long) getpid ()); if (!g_file_make_symbolic_link (self->transaction_lock_path, transaction_str, cancellable, error)) @@ -942,6 +988,65 @@ ostree_repo_prepare_transaction (OstreeRepo *self, return ret; } +static gboolean +rename_pending_loose_objects (OstreeRepo *self, + GCancellable *cancellable, + GError **error) +{ + gboolean ret = FALSE; + gs_dirfd_iterator_cleanup GSDirFdIterator child_dfd_iter = { 0, }; + + if (!gs_dirfd_iterator_init_at (self->tmp_dir_fd, self->boot_id, FALSE, &child_dfd_iter, error)) + goto out; + + while (TRUE) + { + struct dirent *out_dent; + + if (!gs_dirfd_iterator_next_dent (&child_dfd_iter, &out_dent, cancellable, error)) + goto out; + + if (out_dent == NULL) + break; + + if (strncmp (out_dent->d_name, "tmpobject-", 10) == 0) + { + char loose_path[_OSTREE_LOOSE_PATH_MAX]; + gs_free gchar *checksum = NULL; + OstreeObjectType type; + ostree_object_from_string (out_dent->d_name + 10, + &checksum, + &type); + + _ostree_loose_path (loose_path, checksum, type, self->mode); + + if (!_ostree_repo_ensure_loose_objdir_at (self->objects_dir_fd, loose_path, + cancellable, error)) + goto out; + + if (G_UNLIKELY (renameat (child_dfd_iter.fd, out_dent->d_name, + self->objects_dir_fd, loose_path) < 0)) + { + (void) unlinkat (self->tmp_dir_fd, out_dent->d_name, 0); + if (errno != EEXIST) + { + gs_set_error_from_errno (error, errno); + g_prefix_error (error, "Storing file '%s': ", loose_path); + goto out; + } + } + continue; + } + } + + if (!gs_shutil_rm_rf_at (self->tmp_dir_fd, self->boot_id, cancellable, error)) + goto out; + + ret = TRUE; + out: + return ret; +} + static gboolean cleanup_tmpdir (OstreeRepo *self, GCancellable *cancellable, @@ -1109,6 +1214,15 @@ ostree_repo_commit_transaction (OstreeRepo *self, g_return_val_if_fail (self->in_transaction == TRUE, FALSE); + if (syncfs (self->tmp_dir_fd) < 0) + { + gs_set_error_from_errno (error, errno); + goto out; + } + + if (! rename_pending_loose_objects (self, cancellable, error)) + goto out; + if (!cleanup_tmpdir (self, cancellable, error)) goto out; diff --git a/src/libostree/ostree-repo-private.h b/src/libostree/ostree-repo-private.h index b36e6d94..b7f926d8 100644 --- a/src/libostree/ostree-repo-private.h +++ b/src/libostree/ostree-repo-private.h @@ -34,6 +34,8 @@ G_BEGIN_DECLS struct OstreeRepo { GObject parent; + char *boot_id; + GFile *repodir; GFile *tmp_dir; int tmp_dir_fd; @@ -82,6 +84,11 @@ _ostree_repo_ensure_loose_objdir_at (int dfd, const char *loose_path, GCancellable *cancellable, GError **error); +void +_ostree_repo_get_tmpobject_path (OstreeRepo *repo, + char *output, + const char *checksum, + OstreeObjectType objtype); gboolean _ostree_repo_find_object (OstreeRepo *self, @@ -101,6 +108,7 @@ _ostree_repo_has_loose_object (OstreeRepo *self, OstreeObjectType objtype, gboolean *out_is_stored, char *loose_path_buf, + GFile **out_stored_path, GCancellable *cancellable, GError **error); diff --git a/src/libostree/ostree-repo.c b/src/libostree/ostree-repo.c index f27911de..d98ea0b7 100644 --- a/src/libostree/ostree-repo.c +++ b/src/libostree/ostree-repo.c @@ -326,6 +326,7 @@ ostree_repo_finalize (GObject *object) g_clear_object (&self->parent_repo); + g_free (self->boot_id); g_clear_object (&self->repodir); g_clear_object (&self->tmp_dir); if (self->tmp_dir_fd) @@ -1277,6 +1278,16 @@ ostree_repo_open (OstreeRepo *self, if (self->inited) return TRUE; + /* We use a per-boot identifier to keep track of which file contents + * possibly haven't been sync'd to disk. + */ + if (!g_file_get_contents ("/proc/sys/kernel/random/boot_id", + &self->boot_id, + NULL, + error)) + goto out; + g_strdelimit (self->boot_id, "\n", '\0'); + if (!gs_file_open_dir_fd (self->objects_dir, &self->objects_dir_fd, cancellable, error)) { g_prefix_error (error, "Reading objects/ directory: "); @@ -1715,6 +1726,13 @@ load_metadata_internal (OstreeRepo *self, cancellable, error)) goto out; + if (self->in_transaction && fd < 0) + { + _ostree_repo_get_tmpobject_path (self, loose_path_buf, sha256, objtype); + if (!openat_allow_noent (self->tmp_dir_fd, loose_path_buf, &fd, cancellable, error)) + goto out; + } + if (fd != -1) { if (out_variant) @@ -2111,27 +2129,55 @@ _ostree_repo_has_loose_object (OstreeRepo *self, OstreeObjectType objtype, gboolean *out_is_stored, char *loose_path_buf, + GFile **out_stored_path, GCancellable *cancellable, GError **error) { gboolean ret = FALSE; struct stat stbuf; - int res; + int res = -1; + gboolean tmp_file = FALSE; - _ostree_loose_path (loose_path_buf, checksum, objtype, self->mode); - - do - res = fstatat (self->objects_dir_fd, loose_path_buf, &stbuf, AT_SYMLINK_NOFOLLOW); - while (G_UNLIKELY (res == -1 && errno == EINTR)); - if (res == -1 && errno != ENOENT) + if (self->in_transaction) { - gs_set_error_from_errno (error, errno); - goto out; + _ostree_repo_get_tmpobject_path (self, loose_path_buf, checksum, objtype); + do + res = fstatat (self->tmp_dir_fd, loose_path_buf, &stbuf, AT_SYMLINK_NOFOLLOW); + while (G_UNLIKELY (res == -1 && errno == EINTR)); + if (res == -1 && errno != ENOENT) + { + gs_set_error_from_errno (error, errno); + goto out; + } + } + + if (res == 0) + tmp_file = TRUE; + else + { + _ostree_loose_path (loose_path_buf, checksum, objtype, self->mode); + + do + res = fstatat (self->objects_dir_fd, loose_path_buf, &stbuf, AT_SYMLINK_NOFOLLOW); + while (G_UNLIKELY (res == -1 && errno == EINTR)); + if (res == -1 && errno != ENOENT) + { + gs_set_error_from_errno (error, errno); + goto out; + } } ret = TRUE; *out_is_stored = (res != -1); - out: + + if (out_stored_path) + { + if (res != -1) + *out_stored_path = g_file_resolve_relative_path (tmp_file ? self->tmp_dir : self->objects_dir, loose_path_buf); + else + *out_stored_path = NULL; + } +out: return ret; } @@ -2143,21 +2189,10 @@ _ostree_repo_find_object (OstreeRepo *self, GCancellable *cancellable, GError **error) { - gboolean ret = FALSE; gboolean has_object; char loose_path[_OSTREE_LOOSE_PATH_MAX]; - - if (!_ostree_repo_has_loose_object (self, checksum, objtype, &has_object, loose_path, - cancellable, error)) - goto out; - - ret = TRUE; - if (has_object) - *out_stored_path = g_file_resolve_relative_path (self->objects_dir, loose_path); - else - *out_stored_path = NULL; -out: - return ret; + return _ostree_repo_has_loose_object (self, checksum, objtype, &has_object, loose_path, + out_stored_path, cancellable, error); } /**