Commit graph

642 commits

Author SHA1 Message Date
Eelco Dolstra
d950cfe70b Check if MS_PRIVATE is defined
http://hydra.nixos.org/build/2955671
2012-08-20 15:55:49 -04:00
Eelco Dolstra
56e30e161c In the chroot, make all mounted filesystems private
This is required on systemd, which mounts filesystems as "shared"
subtrees.  Changes to shared trees in a private mount namespace are
propagated to the outside world, which is bad.
2012-08-20 15:27:30 -04:00
Eelco Dolstra
f0eab0636b Don't bind-mount /proc since we mount our own 2012-08-20 15:27:00 -04:00
Eelco Dolstra
862c4c5ec5 Fix 1755 permission on temporary directories left behind by ‘-K’ 2012-08-19 16:32:42 -04:00
Eelco Dolstra
325d1cfebf Don't warn about maximum link count exceeded on 0-byte files 2012-08-07 16:22:54 -04:00
Eelco Dolstra
d025142f52 Handle amount of disk space saved by hard linking being negative
Fixes bogus messages like "currently hard linking saves
17592186044416.00 MiB".
2012-08-05 21:45:27 -04:00
Eelco Dolstra
b6c989b801 Fix race condition when two processes create a hard link to a file in .links
This is a problem because one process may set the immutable bit before
the second process has created its link.

Addressed random Hydra failures such as:

error: cannot rename `/nix/store/.tmp-link-17397-1804289383' to
`/nix/store/rsvzm574rlfip3830ac7kmaa028bzl6h-nixos-0.1pre-git/upstart-interface-version':
Operation not permitted
2012-08-05 21:41:44 -04:00
Eelco Dolstra
108e14bb18 Fix race condition when two processes create the same link in /nix/store/.links 2012-08-05 18:17:55 -04:00
Eelco Dolstra
6763084ae5 Count bytes freed deleting unused links 2012-08-01 22:43:03 -04:00
Eelco Dolstra
01d56c1eec Drop the block count in the garbage collector 2012-08-01 22:34:46 -04:00
Eelco Dolstra
967d066d8e nix-store --gc: Make ‘--max-freed 0’ do the right thing
That is, delete almost nothing (it will still remove unused links from
/nix/store/.links).
2012-08-01 19:14:58 -04:00
Eelco Dolstra
1df702d347 removeUnusedLinks(): Print stats on disk space saved by hard linking 2012-08-01 19:01:50 -04:00
Eelco Dolstra
234ce610e0 Doh 2012-08-01 16:09:47 -04:00
Eelco Dolstra
7b10562370 Make ‘nix-store --optimise’ interruptible 2012-08-01 16:06:49 -04:00
Eelco Dolstra
3a4623afbb Set permissions on temporary build directories to 0700
Fixes #39.
2012-07-26 15:04:40 -04:00
Eelco Dolstra
e98c029717 Handle platforms that don't support linking to a symlink
E.g. Darwin doesn't allow this.
2012-07-23 18:42:18 -04:00
Eelco Dolstra
fd63c8bfcd Unlink the right file 2012-07-23 18:06:37 -04:00
Eelco Dolstra
680ab6f83d Garbage collect unused links in /nix/store/.links
Incremental optimisation requires creating links in /nix/store/.links
to all files in the store.  However, this means that if we delete a
store path, no files are actually deleted because links in
/nix/store/.links still exists.  So we need to check /nix/store/.links
for files with a link count of 1 and delete them.
2012-07-23 17:14:16 -04:00
Eelco Dolstra
6193105710 Automatically optimise the Nix store when a new path is added
Auto-optimisation is enabled by default.  It can be turned off by
setting auto-optimise-store to false in nix.conf.
2012-07-23 17:14:15 -04:00
Eelco Dolstra
564fb7d9fa optimiseStore(): Use a content-addressed file store in /nix/store/.links
optimiseStore() now creates persistent, content-addressed hard links
in /nix/store/.links.  For instance, if it encounters a file P with
hash H, it will create a hard link

  P' = /nix/store/.link/<H>

to P if P' doesn't already exist; if P' exist, then P is replaced by a
hard link to P'.  This is better than the previous in-memory map,
because it had the tendency to unnecessarily replace hard links with a
hard link to whatever happened to be the first file with a given hash
it encountered.  It also allows on-the-fly, incremental optimisation.
2012-07-23 17:14:15 -04:00
Eelco Dolstra
6852289c46 Use lutimes() if available to canonicalise the timestamp of symlinks
Also use utimes() instead of utime() if lutimes() is not available.
2012-07-23 16:52:25 -04:00
Eelco Dolstra
b7fd2c2822 Use "#pragma once" to prevent repeated header file inclusion 2012-07-18 14:59:03 -04:00
Eelco Dolstra
ccc52adfb2 Add function queryPathFromHashPart()
To implement binary caches efficiently, Hydra needs to be able to map
the hash part of a store path (e.g. "gbg...zr7") to the full store
path (e.g. "/nix/store/gbg...kzr7-subversion-1.7.5").  (The binary
cache mechanism uses hash parts as a key for looking up store paths to
ensure privacy.)  However, doing a search in the Nix store for
/nix/store/<hash>* is expensive since it requires reading the entire
directory.  queryPathFromHashPart() prevents this by doing a cheap
database lookup.
2012-07-17 18:55:39 -04:00
Eelco Dolstra
3a9fdf2747 Return an exit code of 100 for cached failed builds
Exit code 100 should be returned for all permanent failures.  This
includes cached failures.

Fixes #34.
2012-07-17 15:55:30 -04:00
Eelco Dolstra
6c01fb4d68 Update Nix 1.1 release notes 2012-07-17 10:06:20 -04:00
Eelco Dolstra
53b24f3518 Allow disabling log compression 2012-07-17 09:40:12 -04:00
Eelco Dolstra
1aba0bf0fa nix-store -r: do substitutions in parallel
I.e. when multiple non-derivation arguments are passed to ‘nix-store
-r’ to be substituted, do them in parallel.
2012-06-27 16:58:15 -04:00
Eelco Dolstra
42f5a2fc29 Mount an empty /dev/shm tmpfs in the chroot
This ensures that whatever the builder writes in /dev/shm is
automatically cleaned up.
2012-06-27 09:52:27 -04:00
Eelco Dolstra
3ee208516f Check the return code of the clone() call 2012-06-27 09:52:06 -04:00
Eelco Dolstra
1db38ae81b When using chroots, use a private PID namespace
In a private PID namespace, processes have PIDs that are separate from
the rest of the system.  The initial child gets PID 1.  Processes in
the chroot cannot see processes outside of the chroot.  This improves
isolation between builds.  However, processes on the outside can see
processes in the chroot and send signals to them (if they have
appropriate rights).

Since the builder gets PID 1, it serves as the reaper for zombies in
the chroot.  This might turn out to be a problem.  In that case we'll
need to have a small PID 1 process that sits in a loop calling wait().
2012-06-25 15:45:16 -04:00
Eelco Dolstra
5489086456 Use a private UTS namespace to provide a deterministic host/domain name to builders
In chroot builds, set the host name to "localhost" and the domain name
to "(none)" (the latter being the kernel's default).  This improves
determinism a bit further.

P.S. I have to idea what UTS stands for.
2012-06-25 14:12:17 -04:00
Eelco Dolstra
723a68c826 Improve error message 2012-06-23 00:57:14 -04:00
Eelco Dolstra
7ffa523fd1 In chroot builds, use a private SysV IPC namespace
This improves isolation a bit further, and it's just one extra flag in
the unshare() call.

P.S. It would be very cool to use CLONE_NEWPID (to put the builder in
a private PID namespace) as well, but that's slightly more risky since
having a builder start as PID 1 may cause problems.
2012-06-23 00:51:40 -04:00
Eelco Dolstra
df716c98d2 In chroot builds, use a private network namespace
On Linux it's possible to run a process in its own network namespace,
meaning that it gets its own set of network interfaces, disjunct from
the rest of the system.  We use this to completely remove network
access to chroot builds, except that they get a private loopback
interface.  This means that:

- Builders cannot connect to the outside network or to other processes
  on the same machine, except processes within the same build.

- Vice versa, other processes cannot connect to processes in a chroot
  build, and open ports/connections do not show up in "netstat".

- If two concurrent builders try to listen on the same port (e.g. as
  part of a test), they no longer conflict with each other.

This was inspired by the "PrivateNetwork" flag in systemd.
2012-06-23 00:28:35 -04:00
Eelco Dolstra
f5398d374b Compress build logs on the fly using bzip2 2012-05-30 10:12:29 -04:00
Eelco Dolstra
4bc4da331a Reserve some disk space for the garbage collector
We can't open a SQLite database if the disk is full.  Since this
prevents the garbage collector from running when it's most needed, we
reserve some dummy space that we can free just before doing a garbage
collection.  This actually revives some old code from the Berkeley DB
days.

Fixes #27.
2012-05-29 22:59:12 -04:00
Eelco Dolstra
2c26985835 Add option ‘build-keep-log’ to enable/disable writing of build logs
Fixes #26.
2012-05-29 16:42:05 -04:00
Eelco Dolstra
db5b86ef13 * Add an option ‘build-use-substitutes’, which can be set to ‘false’
to disable use of substitutes; i.e., force building from source.
  Fixes Nix/221.
2012-04-30 19:15:34 -04:00
Eelco Dolstra
46cdc6ad51 Handle EPERM when creating a hard link for the chroot
There is a race condition when doing parallel builds with chroots and
the immutable bit enabled.  One process may call makeImmutable()
before the other has called link(), in which case link() will fail
with EPERM.  We could retry or wrap the operation in a lock, but since
this condition is rare and I'm lazy, we just use the existing copy
fallback.

Fixes #9.
2012-04-30 10:58:04 -04:00
Eelco Dolstra
6387830c3b Merge pull request #2 from viric/master
Again, adding the sync option
2012-04-23 03:29:03 -07:00
Eelco Dolstra
1132dd27ea Fix obscure race condition in GC root creation
This should fix rare Hydra errors of the form:

error: symlinking `/nix/var/nix/gcroots/per-user/hydra/hydra-roots/7sfhs5fdmjxm8sqgcpd0pgcsmz1kq0l0-nixos-iso-0.1pre33785-33795' to `/nix/store/7sfhs5fdmjxm8sqgcpd0pgcsmz1kq0l0-nixos-iso-0.1pre33785-33795': File exists
2012-04-16 18:47:01 +02:00
Eelco Dolstra
31e34fcf93 Close almost all file descriptors in the builder
This regression was accidentally introduced in
35355fc1fc.
2012-04-15 00:20:32 +02:00
Eelco Dolstra
f2467eb6a0 On Linux, pretend we're building on Linux 2.6
Setting the UNAME26 personality causes "uname" to return "2.6.x",
regardless of the kernel version.  This improves determinism in
a few misbehaved packages.
2012-04-05 13:03:19 +02:00
Eelco Dolstra
446b827bae Mac OS X fix 2012-03-26 23:18:36 +02:00
Eelco Dolstra
480dda0e42 Delete non-directory valid paths right away
It's unlikely that rename() is faster than unlink() on a regular file
or symlink, so don't bother.
2012-03-26 20:56:30 +02:00
Eelco Dolstra
117670be57 Make the garbage collector more concurrent
Make the garbage collector more concurrent by deleting valid paths
outside the region where we're holding the global GC lock.  This
should greatly reduce the time during which new builds are blocked,
since the deletion accounts for the vast majority of the time spent in
the GC.

To ensure that this is safe, the valid paths are invalidated and
renamed to some arbitrary path while we're holding the lock.  This
ensures that we when we finally delete the path, it's not a (newly)
valid or locked path.
2012-03-26 20:43:33 +02:00
Eelco Dolstra
8be1979f1a Remove the --max-links GC option
We don't need this anymore now that current filesystems support more
than 32,000 files in a directory.
2012-03-26 20:00:02 +02:00
Lluís Batlle i Rossell
85799bf89e Fixing the default of sync-before-registering
Setting 'false' as default, as suggested by Eelco.

I also added a comment about the setting in the code.
2012-03-22 20:05:54 +01:00
Lluís Batlle i Rossell
25de80e2b6 Adding a nix option to sync before registering a path, for non-ext*
filesystems.
2012-03-22 19:57:42 +01:00
Eelco Dolstra
19d9762ad5 nix-store --clear-failed-paths: Clear derivation outputs
If the argument to ‘nix-store --clear-failed-paths’ is a derivation,
then clear the failed state of its outputs.
2012-03-20 18:23:26 +01:00