The following commit has been merged in the master branch:
commit 9cd41fdda1c27169c52d73b3b3ce71991d724994
Author: Guillem Jover <[email protected]>
Date: Sun Mar 21 09:23:09 2010 +0100
dpkg: Defer the fsync and rename for normal files in tar extraction
This way it's done in one pass afterwards, to avoid massive I/O
degradation due to the serialization from each write + fsync. This
restores extraction times to numbers closer to the ones before the
fsync patch introduced in 1.15.6.
diff --git a/debian/changelog b/debian/changelog
index a17d260..60aefd2 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -12,6 +12,10 @@ dpkg (1.15.6.1) UNRELEASED; urgency=low
the code to use STL's min() and max() instead of preprocessor macros, to
avoid multiple evaluation of arguments. Regression introduced in 1.15.6.
Based on a patch by Robert Luberda <[email protected]>. Closes: #574816
+ * Defer the fsync and rename for normal files in tar extraction so that
+ it's done in one pass afterwards, to avoid massive I/O degradation due to
+ the serialization from each write + fsync. This restores extraction times
+ to numbers closer to the ones before the fsync patch introduced in 1.15.6.
[ Raphaël Hertzog ]
* Accept source packages without "Format" field for compatibility with very
diff --git a/src/archives.c b/src/archives.c
index 1f3663f..79fef4e 100644
--- a/src/archives.c
+++ b/src/archives.c
@@ -661,8 +661,10 @@ int tarobject(struct TarInfo *ti) {
am=(nifd->namenode->statoverride ? nifd->namenode->statoverride->mode :
ti->Mode) & ~S_IFMT;
if (fchmod(fd,am))
ohshite(_("error setting permissions of `%.255s'"),ti->Name);
- if (fsync(fd))
- ohshite(_("unable to sync file '%.255s'"), ti->Name);
+
+ /* Postpone the fsync, to try to avoid massive I/O degradation. */
+ nifd->namenode->flags |= fnnf_deferred_fsync;
+
pop_cleanup(ehflag_normaltidy); /* fd= open(fnamenewvb.buf) */
if (close(fd))
ohshite(_("error closing/writing `%.255s'"),ti->Name);
@@ -777,22 +779,82 @@ int tarobject(struct TarInfo *ti) {
* in dpkg-new.
*/
- if (rename(fnamenewvb.buf,fnamevb.buf))
- ohshite(_("unable to install new version of `%.255s'"),ti->Name);
+ if (ti->Type == NormalFile0 || ti->Type == NormalFile0) {
+ nifd->namenode->flags |= fnnf_deferred_rename;
- /* CLEANUP: now the new file is in the destination file, and the
- * old file is in dpkg-tmp to be cleaned up later. We now need
- * to take a different attitude to cleanup, because we need to
- * remove the new file.
- */
+ debug(dbg_eachfiledetail, "tarobject done and installation deferred");
+ } else {
+ if (rename(fnamenewvb.buf, fnamevb.buf))
+ ohshite(_("unable to install new version of `%.255s'"), ti->Name);
- nifd->namenode->flags |= fnnf_placed_on_disk;
- nifd->namenode->flags |= fnnf_elide_other_lists;
+ /* CLEANUP: now the new file is in the destination file, and the
+ * old file is in dpkg-tmp to be cleaned up later. We now need
+ * to take a different attitude to cleanup, because we need to
+ * remove the new file. */
+
+ nifd->namenode->flags |= fnnf_placed_on_disk;
+ nifd->namenode->flags |= fnnf_elide_other_lists;
+
+ debug(dbg_eachfiledetail, "tarobject done and installed");
+ }
- debug(dbg_eachfiledetail,"tarobject done and installed");
return 0;
}
+void
+tar_deferred_extract(struct pkginfo *pkg)
+{
+ struct fileinlist *cfile;
+ struct filenamenode *usenode;
+ const char *usename;
+
+ for (cfile = pkg->clientdata->files; cfile; cfile = cfile->next) {
+ debug(dbg_eachfile, "deferred extract of '%.255s'", cfile->namenode->name);
+
+ if (!(cfile->namenode->flags & fnnf_deferred_rename))
+ continue;
+
+ debug(dbg_eachfiledetail, "deferred extract needs rename");
+
+ usenode = namenodetouse(cfile->namenode, pkg);
+ usename = usenode->name + 1; /* Skip the leading '/'. */
+
+ setupfnamevbs(usename);
+
+ if (cfile->namenode->flags & fnnf_deferred_fsync) {
+ int fd;
+
+ debug(dbg_eachfiledetail, "deferred extract needs fsync");
+
+ fd = open(fnamenewvb.buf, O_WRONLY);
+ if (fd < 0)
+ ohshite(_("unable to open '%.255s'"), fnamenewvb.buf);
+ if (fsync(fd))
+ ohshite(_("unable to sync file '%.255s'"), fnamenewvb.buf);
+ if (close(fd))
+ ohshite(_("error closing/writing `%.255s'"), fnamenewvb.buf);
+
+ cfile->namenode->flags &= ~fnnf_deferred_fsync;
+ }
+
+ if (rename(fnamenewvb.buf, fnamevb.buf))
+ ohshite(_("unable to install new version of `%.255s'"),
+ cfile->namenode->name);
+
+ cfile->namenode->flags &= ~fnnf_deferred_rename;
+
+ /* CLEANUP: now the new file is in the destination file, and the
+ * old file is in dpkg-tmp to be cleaned up later. We now need
+ * to take a different attitude to cleanup, because we need to
+ * remove the new file. */
+
+ cfile->namenode->flags |= fnnf_placed_on_disk;
+ cfile->namenode->flags |= fnnf_elide_other_lists;
+
+ debug(dbg_eachfiledetail, "deferred extract done and installed");
+ }
+}
+
static int
try_deconfigure_can(bool (*force_p)(struct deppossi *), struct pkginfo *pkg,
struct deppossi *pdep, const char *action,
diff --git a/src/archives.h b/src/archives.h
index 7da1561..2390bb8 100644
--- a/src/archives.h
+++ b/src/archives.h
@@ -66,6 +66,7 @@ int unlinkorrmdir(const char *filename);
int tarobject(struct TarInfo *ti);
int tarfileread(void *ud, char *buf, int len);
+void tar_deferred_extract(struct pkginfo *pkg);
bool filesavespackage(struct fileinlist *, struct pkginfo *,
struct pkginfo *pkgbeinginstalled);
diff --git a/src/filesdb.h b/src/filesdb.h
index ac7c274..45a3bf5 100644
--- a/src/filesdb.h
+++ b/src/filesdb.h
@@ -69,6 +69,8 @@ struct filenamenode {
fnnf_elide_other_lists= 000010, /* must remove from other packages'
lists */
fnnf_no_atomic_overwrite= 000020, /* >=1 instance is a dir, cannot rename
over */
fnnf_placed_on_disk= 000040, /* new file has been placed on the disk
*/
+ fnnf_deferred_fsync = 000200,
+ fnnf_deferred_rename = 000400,
} flags; /* Set to zero when a new node is created. */
const char *oldhash; /* valid iff this namenode is in the newconffiles list
*/
struct stat *filestat;
diff --git a/src/processarc.c b/src/processarc.c
index 9a0fa15..fe5ca1f 100644
--- a/src/processarc.c
+++ b/src/processarc.c
@@ -639,6 +639,8 @@ void process_archive(const char *filename) {
p1[0] = -1;
subproc_wait_check(c1, BACKEND " --fsys-tarfile", PROCPIPE);
+ tar_deferred_extract(pkg);
+
if (oldversionstatus == stat_halfinstalled || oldversionstatus ==
stat_unpacked) {
/* Packages that were in `installed' and `postinstfailed' have been reduced
* to `unpacked' by now, by the running of the prerm script.
--
dpkg's main repository
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