Hardlinks are lost by git build cacher #827
Comments
|
I spiked up something to track hardlinks in the commit message of the build cache. master...richardc:rc-spike-hardlink-recording It does fix it for my reproduction, but it's a little messy and is possibly a wrong-headed approach |
avar
added a commit
to avar/git
that referenced
this issue
Mar 13, 2018
Add a INSTALL_SYMLINKS option which if enabled, changes the default
hardlink installation method to one where the relevant binaries in
libexec/git-core are symlinked back to ../../bin, instead of being
hardlinked.
This new option also overrides the behavior of the existing
NO_*_HARDLINKS variables which in some cases would produce symlinks
within to libexec/, e.g. "git-add" symlinked to "git" which would be
copy of the "git" found in bin/, now "git-add" in libexec/ is always
going to be symlinked to the "git" found in the bin/ directory.
This option is being added because:
1) I think it makes what we're doing a lot more obvious. E.g. I'd
never noticed that the libexec binaries were really just hardlinks
since e.g. ls(1) won't show that in any obvious way. You need to
start stat(1)-ing things and look at the inodes to see what's
going on.
2) Some tools have very crappy support for hardlinks, e.g. the Git
shipped with GitLab is much bigger than it should be because
they're using a chef module that doesn't know about hardlinks, see
chef/omnibus#827
I've also ran into other related issues that I think are explained
by this, e.g. compiling git with debugging and rpm refusing to
install a ~200MB git package with 2GB left on the FS, I think that
was because it doesn't consider hardlinks, just the sum of the
byte size of everything in the package.
As for the implementation, the "../../bin" noted above will vary given
some given some values of "../.." and "bin" depending on the depth of
the gitexecdir relative to the destdir, and the "bindir" target,
e.g. setting "bindir=/tmp/git/binaries gitexecdir=foo/bar/baz" will do
the right thing and produce this result:
$ file /tmp/git/foo/bar/baz/git-add
/tmp/git/foo/bar/baz/git-add: symbolic link to ../../../binaries/git
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
avar
added a commit
to avar/git
that referenced
this issue
Mar 14, 2018
Add a INSTALL_SYMLINKS option which if enabled, changes the default
hardlink installation method to one where the relevant binaries in
libexec/git-core are symlinked back to ../../bin, instead of being
hardlinked.
This new option also overrides the behavior of the existing
NO_*_HARDLINKS variables which in some cases would produce symlinks
within to libexec/, e.g. "git-add" symlinked to "git" which would be
copy of the "git" found in bin/, now "git-add" in libexec/ is always
going to be symlinked to the "git" found in the bin/ directory.
This option is being added because:
1) I think it makes what we're doing a lot more obvious. E.g. I'd
never noticed that the libexec binaries were really just hardlinks
since e.g. ls(1) won't show that in any obvious way. You need to
start stat(1)-ing things and look at the inodes to see what's
going on.
2) Some tools have very crappy support for hardlinks, e.g. the Git
shipped with GitLab is much bigger than it should be because
they're using a chef module that doesn't know about hardlinks, see
chef/omnibus#827
I've also run into other related issues that I think are explained
by this, e.g. compiling git with debugging and rpm refusing to
install a ~200MB git package with 2GB left on the FS, I think that
was because it doesn't consider hardlinks, just the sum of the
byte size of everything in the package.
As for the implementation, the "../../bin" noted above will vary given
some values of "../.." and "bin" depending on the depth of the
gitexecdir relative to the destdir, and the "bindir" target,
e.g. setting "bindir=/tmp/git/binaries gitexecdir=foo/bar/baz" will do
the right thing and produce this result:
$ file /tmp/git/foo/bar/baz/git-add
/tmp/git/foo/bar/baz/git-add: symbolic link to ../../../binaries/git
FIXME: Needs to actually be rebased on the NO_INSTALL_CP_FALLBACK
change, now it just clobbers it.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
gitster
pushed a commit
to git/git
that referenced
this issue
Mar 15, 2018
Add a INSTALL_SYMLINKS option which if enabled, changes the default
hardlink installation method to one where the relevant binaries in
libexec/git-core are symlinked back to ../../bin, instead of being
hardlinked.
This new option also overrides the behavior of the existing
NO_*_HARDLINKS variables which in some cases would produce symlinks
within to libexec/, e.g. "git-add" symlinked to "git" which would be
copy of the "git" found in bin/, now "git-add" in libexec/ is always
going to be symlinked to the "git" found in the bin/ directory.
This option is being added because:
1) I think it makes what we're doing a lot more obvious. E.g. I'd
never noticed that the libexec binaries were really just hardlinks
since e.g. ls(1) won't show that in any obvious way. You need to
start stat(1)-ing things and look at the inodes to see what's
going on.
2) Some tools have very crappy support for hardlinks, e.g. the Git
shipped with GitLab is much bigger than it should be because
they're using a chef module that doesn't know about hardlinks, see
chef/omnibus#827
I've also ran into other related issues that I think are explained
by this, e.g. compiling git with debugging and rpm refusing to
install a ~200MB git package with 2GB left on the FS, I think that
was because it doesn't consider hardlinks, just the sum of the
byte size of everything in the package.
As for the implementation, the "../../bin" noted above will vary given
some given some values of "../.." and "bin" depending on the depth of
the gitexecdir relative to the destdir, and the "bindir" target,
e.g. setting "bindir=/tmp/git/binaries gitexecdir=foo/bar/baz" will do
the right thing and produce this result:
$ file /tmp/git/foo/bar/baz/git-add
/tmp/git/foo/bar/baz/git-add: symbolic link to ../../../binaries/git
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
dscho
pushed a commit
to git-for-windows/git
that referenced
this issue
May 29, 2018
Add a INSTALL_SYMLINKS option which if enabled, changes the default
hardlink installation method to one where the relevant binaries in
libexec/git-core are symlinked back to ../../bin, instead of being
hardlinked.
This new option also overrides the behavior of the existing
NO_*_HARDLINKS variables which in some cases would produce symlinks
within to libexec/, e.g. "git-add" symlinked to "git" which would be
copy of the "git" found in bin/, now "git-add" in libexec/ is always
going to be symlinked to the "git" found in the bin/ directory.
This option is being added because:
1) I think it makes what we're doing a lot more obvious. E.g. I'd
never noticed that the libexec binaries were really just hardlinks
since e.g. ls(1) won't show that in any obvious way. You need to
start stat(1)-ing things and look at the inodes to see what's
going on.
2) Some tools have very crappy support for hardlinks, e.g. the Git
shipped with GitLab is much bigger than it should be because
they're using a chef module that doesn't know about hardlinks, see
chef/omnibus#827
I've also ran into other related issues that I think are explained
by this, e.g. compiling git with debugging and rpm refusing to
install a ~200MB git package with 2GB left on the FS, I think that
was because it doesn't consider hardlinks, just the sum of the
byte size of everything in the package.
As for the implementation, the "../../bin" noted above will vary given
some given some values of "../.." and "bin" depending on the depth of
the gitexecdir relative to the destdir, and the "bindir" target,
e.g. setting "bindir=/tmp/git/binaries gitexecdir=foo/bar/baz" will do
the right thing and produce this result:
$ file /tmp/git/foo/bar/baz/git-add
/tmp/git/foo/bar/baz/git-add: symbolic link to ../../../binaries/git
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
dscho
pushed a commit
to git-for-windows/git
that referenced
this issue
May 29, 2018
Add a INSTALL_SYMLINKS option which if enabled, changes the default
hardlink installation method to one where the relevant binaries in
libexec/git-core are symlinked back to ../../bin, instead of being
hardlinked.
This new option also overrides the behavior of the existing
NO_*_HARDLINKS variables which in some cases would produce symlinks
within to libexec/, e.g. "git-add" symlinked to "git" which would be
copy of the "git" found in bin/, now "git-add" in libexec/ is always
going to be symlinked to the "git" found in the bin/ directory.
This option is being added because:
1) I think it makes what we're doing a lot more obvious. E.g. I'd
never noticed that the libexec binaries were really just hardlinks
since e.g. ls(1) won't show that in any obvious way. You need to
start stat(1)-ing things and look at the inodes to see what's
going on.
2) Some tools have very crappy support for hardlinks, e.g. the Git
shipped with GitLab is much bigger than it should be because
they're using a chef module that doesn't know about hardlinks, see
chef/omnibus#827
I've also ran into other related issues that I think are explained
by this, e.g. compiling git with debugging and rpm refusing to
install a ~200MB git package with 2GB left on the FS, I think that
was because it doesn't consider hardlinks, just the sum of the
byte size of everything in the package.
As for the implementation, the "../../bin" noted above will vary given
some given some values of "../.." and "bin" depending on the depth of
the gitexecdir relative to the destdir, and the "bindir" target,
e.g. setting "bindir=/tmp/git/binaries gitexecdir=foo/bar/baz" will do
the right thing and produce this result:
$ file /tmp/git/foo/bar/baz/git-add
/tmp/git/foo/bar/baz/git-add: symbolic link to ../../../binaries/git
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Description
The build cache does not preserve hardlinks in the install directory. This means things like git end up with the version in
embedded/bin/gitand a copy (installed by the software definition as a hardlink) asembedded/libexec/git-core/gitOmnibus Version
5.6.10 Reproduced with master@9a3a97bb0c6b
Platform Version
CentOS7
omnibus 9a3a97b
Replication Case
https://gitlab.com/richardc/omnibus-helloworld/tree/git-hardlink-caches
The
hardlinksproject deliberately creates a hardlink from"#{install_dir}/bin/helloworld"On first run, this correctly creates a hardlinked file in the output directory, and the resulting packages also feature hardlinks:
(Link count of 2 in the second column)
On a subsequent build, and a build cache hit, they are present as two identical files, not the expected hardlink.
The text was updated successfully, but these errors were encountered: