[Yum] [PATCH 4 of 4] hard link packages between local caches

Daniel P. Berrange berrange at redhat.com
Wed May 30 18:15:40 UTC 2007


When syncing multiple repositories across many architectures there will be
a fairly large number of duplicate RPMs present in all repositories. This
is particularly true of x86_64 multilib distros which share most of the
i386 packages. Downloading many GB of packages for x86_64 repo which are
already present in a i386 synced repo is wasteful of time, disk space and
bandwidth. So this patch adds an extra argument --package-cache which takes
a directory path. This argument can be repeated multiple times. Before 
downloading a package, reposync will check each of these directories to see
if they already contain a copy of the package. If so, the local package will
be hard-linked into the destdir.

Typical usage would be to list the i386 repo cache, when running a sync of
the x86_64 repository, and vica-verca.

To give an idea of the saving, Fedora rawhide currently has ~7400 rpms in
i386 repos, and 13,000 in x86_64 trees. ~6900 of these RPMs where present
in both trees. Hardlinking saved 8 GB of disk space & avoid 8 GB of file
downloads :-)

Dan
--
|=- Red Hat, Engineering, Emerging Technologies, Boston.  +1 978 392 2496 -=|
|=-           Perl modules: http://search.cpan.org/~danberr/              -=|
|=-               Projects: http://freshmeat.net/~danielpb/               -=|
|=-  GnuPG: 7D3B9505   F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505  -=| 
-------------- next part --------------
diff -r 09e3be327b9e reposync.py
--- a/reposync.py	Wed May 30 13:26:50 2007 -0400
+++ b/reposync.py	Wed May 30 13:26:53 2007 -0400
@@ -103,6 +103,8 @@ def parseArgs():
         help="Use a temp dir for storing/accessing yum-cache")
     parser.add_option("-d", "--delete", default=False, action="store_true",
         help="delete local packages no longer present in repository")
+    parser.add_option("-k", "--package-cache", default=[], dest='pkgcache', action='append',
+        help="additional directory to search for pre-existing packages")
     parser.add_option("-p", "--download_path", dest='destdir', 
         default=os.getcwd(), help="Path to download packages to: defaults to current dir")
     parser.add_option("-g", "--gpgcheck", default=False, action="store_true",
@@ -135,6 +137,14 @@ def main():
     my = RepoSync(opts=opts)
     my.doConfigSetup(fn=opts.config, init_plugins=False)
 
+    # Populate cache of existing download RPMs from other
+    # repositories we can link to
+    pkgcache = {}
+    for dir in opts.pkgcache:
+        cache = localpkgs(dir)
+        for k in cache.keys():
+            pkgcache[k] = cache[k]
+
     # Force unprivileged users to have a private temporary cachedir
     # if they've not given an explicit cachedir
     if os.getuid() != 0 and not opts.cachedir:
@@ -183,7 +193,18 @@ def main():
             download_list = list(reposack)
 
         local_repo_path = opts.destdir + '/' + repo.id
-        if opts.delete and os.path.exists(local_repo_path):
+        # make sure the repo subdir is here before we go on.
+        if not os.path.exists(local_repo_path):
+            try:
+                os.makedirs(local_repo_path)
+            except IOError, e:
+                my.logger.error("Could not make repo subdir: %s" % e)
+                my.closeRpmDB()
+                sys.exit(1)
+
+        # Check if there's any local files no longer on the remote
+        # repo which need purging
+        if opts.delete:
             current_pkgs = localpkgs(local_repo_path)
 
             download_set = {}
@@ -199,6 +220,7 @@ def main():
                 if not opts.quiet:
                     my.logger.info("Removing obsolete %s", pkg)
                 os.unlink(current_pkgs[pkg]['path'])
+
 
         download_list.sort(sortPkgObj)
         n = 0
@@ -206,47 +228,63 @@ def main():
             n = n + 1
             repo = my.repos.getRepo(pkg.repoid)
             remote = pkg.returnSimple('relativepath')
+            rpmname = os.path.basename(remote)
             local = local_repo_path + '/' + remote
             localdir = os.path.dirname(local)
+            pkg.localpath = local # Hack: to set the localpath we want.
             if not os.path.exists(localdir):
                 os.makedirs(localdir)
 
-            if (os.path.exists(local) and 
+            # If we have a local RPM with same name, and it is
+            # on the same storage device, and it has same size
+            # then we can hardlink it into local dir.
+            if (not os.path.exists(local) and
+                pkgcache.has_key(rpmname) and
+                os.stat(local_repo_path).st_dev == pkgcache[rpmname]['device'] and
+                pkgcache[rpmname]['size'] == int(pkg.returnSimple('packagesize'))):
+
+                if not opts.quiet:
+                    my.logger.info("[%s: %-5d of %-5d ] Linking existing %s" % (repo.id, n, len(download_list), remote))
+                os.link(pkgcache[rpmname]['path'], local)
+
+            # Optionally check gpg signature of local package
+            if os.path.exists(local) and opts.gpgcheck:
+                result, error = my.sigCheckPkg(pkg)
+                if result != 0:
+                    if not opts.quiet:
+                        my.logger.error("[%s: %-5d of %-5d ] Removing non-matching %s" % (repo.id, n, len(download_list), remote))
+                    os.unlink(local)
+
+            # If we have a local pkg with same name, check its size
+            if (os.path.exists(local) and
                 str(os.path.getsize(local)) == pkg.returnSimple('packagesize')):
                 
                 if not opts.quiet:
                     my.logger.error("[%s: %-5d of %-5d ] Skipping existing %s" % (repo.id, n, len(download_list), remote))
                 continue
-    
+
+            # If we're just printing URLs, skip to next repo
             if opts.urls:
                 url = urljoin(repo.urls[0],remote)
                 print '%s' % url
                 continue
     
-            # make sure the repo subdir is here before we go on.
-            if not os.path.exists(local_repo_path):
-                try:
-                    os.makedirs(local_repo_path)
-                except IOError, e:
-                    my.logger.error("Could not make repo subdir: %s" % e)
-                    my.closeRpmDB()
-                    sys.exit(1)
             
             # Disable cache otherwise things won't download            
             repo.cache = 0
             if not opts.quiet:
                 my.logger.info( '[%s: %-5d of %-5d ] Downloading %s' % (repo.id, n, len(download_list), remote))
-            pkg.localpath = local # Hack: to set the localpath we want.
+
             path = repo.getPackage(pkg)
             if opts.gpgcheck:
                 result, error = my.sigCheckPkg(pkg)
                 if result != 0:
                     if result == 1:
-                        my.logger.warning('Removing %s, due to missing GPG key.' % os.path.basename(remote))
+                        my.logger.warning('Removing %s, due to missing GPG key.' % rpmname)
                     elif result == 2:
-                        my.logger.warning('Removing %s due to failed signature check.' % os.path.basename(remote))
+                        my.logger.warning('Removing %s due to failed signature check.' % rpmname)
                     else:
-                        my.logger.warning('Removing %s due to failed signature check: %s' % (os.path.basename(remote), error))
+                        my.logger.warning('Removing %s due to failed signature check: %s' % (rpmname, error))
                     os.unlink(path)
                     continue
 


More information about the Yum mailing list