I have a buildsystem that targets a number of different distribution
releases, and so I get to rebuild a root cache quite often. Quite
frequently, the creation of the root cache tarball fails and causes the
package build that triggered the root cache creation to fail. However,
simply repeating the build invariably succeeds, and mock uses the
supposedly failed cache tarball from the previous build without problems.
I've not looked at this in detail because the workaround has been so
easy but yesterday I decided to take a look at it. I think there are two
Firstly, the cause of the tarball creation failure. Looking at the root
log, it appeared to be a change in one of the files whilst it was being
archived by tar.
DEBUG util.py, Line: 234: tar:
./usr/lib/locale/locale-archive: file changed as we read it
The same problem with the same file was menioned in a report dating back
two years on fedora-devel-list:
More googling revealed a possible cause of the problem:
So I tried forcing a "sync" before creating the tarball and lo and
behold, the problem went away. I've created at least 20 root caches
since making this change and all worked fine, which I'm very confident
wouldn't have been the case without the "sync". So here's the change I
2009-09-02 19:08:54.000000000 +0100
2009-11-18 15:20:04.353035160 +0000
@@ -110,6 +110,7 @@
# never rebuild cache unless it was a clean build.
+ mock.util.do(["sync"], shell=False)
["tar"] + self.compressArgs + ["-cf",
"-C", self.rootObj.makeChrootPath(), "."],
The second problem is I think that if the "tar" process to create the
tarball fails (and hence causes the resulting build to fail), the cache
should be invalidated so that the next build doesn't use that
presumably-broken tarball. As it happens, a faulty copy of
/usr/lib/locale/locale-archive doesn't seem to cause any problems during
my builds but that may just be my good fortune.