Commit graph

103 commits

Author SHA1 Message Date
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
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
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
Eelco Dolstra
bd50c01972 Ensure that Perl processes delete their entry in the temproots directory
By moving the destructor object to libstore.so, it's also run when
download-using-manifests and nix-prefetch-url exit.  This prevents
them from cluttering /nix/var/nix/temproots with stale files.
2012-03-13 17:07:49 +01:00
Eelco Dolstra
35355fc1fc Set the close-on-exec flag on file descriptors 2012-03-05 20:29:00 +01:00
Eelco Dolstra
58ac7a17a4 Don't use deletePath() to delete a single file 2012-02-15 00:28:01 +01:00
Eelco Dolstra
d5a5a83ad4 Use data() instead of c_str() where appropriate 2012-02-09 18:27:45 +01:00
Eelco Dolstra
6f5e3326ce * Move topoSortPaths() out of gc.cc. 2011-12-30 15:02:50 +00:00
Eelco Dolstra
b1004f40f7 * Reject a build if there is a cycle among the outputs. This is
necessary because existing code assumes that the references graph is
  acyclic.
2011-12-30 14:47:14 +00:00
Eelco Dolstra
524fa8a4f1 * Oops. 2011-12-22 16:27:03 +00:00
Eelco Dolstra
b33da599c5 * In the garbage collector, delete invalid paths before deleting
unreachable paths.  This matters when using --max-freed etc.:
  unreachable paths could become reachable again, so it's nicer to
  keep them if there is "real" garbage to be deleted.  Also, don't use
  readDirectory() but read the Nix store and delete invalid paths in
  parallel.  This reduces GC latency on very large Nix stores.
2011-12-22 15:55:53 +00:00
Eelco Dolstra
58d974336c * Drop unnecessary call to canonPath() (nixStore is already canonical). 2011-12-22 14:33:34 +00:00
Eelco Dolstra
93227ff65c * Eliminate all uses of the global variable ‘store’ from libstore.
This should also fix:

    nix-instantiate: ./../boost/shared_ptr.hpp:254: T* boost::shared_ptr<T>::operator->() const [with T = nix::StoreAPI]: Assertion `px != 0' failed.

  which was caused by hashDerivationModulo() calling the ‘store’
  object (during store upgrades) before openStore() assigned it.
2011-08-31 21:11:50 +00:00
Eelco Dolstra
64fd29855a * Wrap deleteFromStore() in a transaction. Otherwise there might be a
race with other processes that add new referrers to a path,
  resulting in the garbage collector crashing with "foreign key
  constraint failed".  (Nix/4)
* Make --gc --print-dead etc. interruptible.
2010-10-14 15:55:51 +00:00
Eelco Dolstra
e2e168f7c2 `nix-store --verify' improvements:
* If a path has disappeared, check its referrers first, and don't try
  to invalidate paths that have valid referrers.  Otherwise we get a
  foreign key constraint violation.
* Read the whole Nix store directory instead of statting each valid
  path, which is slower.
* Acquire the global GC lock.
2010-08-31 11:47:31 +00:00
Eelco Dolstra
80e722278c * When using the build hook, distinguish between the stderr of the
hook script proper, and the stdout/stderr of the builder.  Only the
  latter should be saved in /nix/var/log/nix/drvs.
* Allow the verbosity to be set through an option.
* Added a flag --quiet to lower the verbosity level.
2010-08-30 14:53:03 +00:00
Eelco Dolstra
20acd43c25 * Disable the GC reachability check for now (when creating new roots),
as it's hopelessly inefficient.
2010-08-30 14:11:57 +00:00
Eelco Dolstra
44f6e6de77 * Set gc-keep-outputs' or gc-keep-derivations' to false with
`--delete --ignore-liveness'.
2010-03-08 21:31:42 +00:00
Eelco Dolstra
c4d388add4 * Get derivation outputs from the database instead of the .drv file,
which requires more I/O.
2010-02-22 12:44:36 +00:00
Eelco Dolstra
103cfee056 * Revert r19650 (implement gc-keep-outputs by looking for derivations
with the same name as the output) and instead use the
  DerivationOutputs table in the database, which is the correct way to
  to do things.
2010-02-22 11:44:17 +00:00
Eelco Dolstra
4bbbe25802 * Remove most Cygwin-specific code. Cygwin 1.7 implements advisory
POSIX locks, and simulates Unix-style file deletion semantics
  sufficiently.  Note that this means that Nix won't work on Cygwin
  1.5 anymore.
2010-02-02 15:28:36 +00:00
Eelco Dolstra
5388944e8d * Make the garbage collector do the right thing when `gc-keep-outputs'
is enabled by not depending on the deriver.
2010-01-25 16:04:32 +00:00
Eelco Dolstra
f9e766db98 * Randomise the order in which we delete entries to make the collector
less biased towards deleting paths that come alphabetically first
  (e.g. /nix/store/000...).  This matters when using --max-freed etc.
2009-11-24 09:53:18 +00:00
Eelco Dolstra
ca50c83fbb 2009-11-23 21:21:29 +00:00
Eelco Dolstra
ae6bf87273 * `nix-store --gc --print-roots': also print the path of the actual
root symlink, not just its target.  E.g.:

  /nix/var/nix/profiles/system-99-link -> /nix/store/76kwf88657nq7wgk1hx3l1z5q91zb9wd-system
2009-11-23 17:23:12 +00:00
Eelco Dolstra
c364d5d1e3 * Made the garbage collector a lot faster. It no longer computes the
complete set of live and dead paths before starting the actual
  deletion, but determines liveness on demand.  I.e. for any path in
  the store, it first tries to delete all the referrers, and then the
  path itself.  This means that the collector can start deleting paths
  almost immediately.
2009-11-23 16:34:24 +00:00
Eelco Dolstra
8824d60fe5 * Remove the --use-atime / --max-atime garbage collector flags. Many
(Linux) machines no longer maintain the atime because it's too
  expensive, and on the machines where --use-atime is useful (like the
  buildfarm), reading the atimes on the entire Nix store takes way too
  much time to make it practical.
2009-11-20 17:12:38 +00:00
Eelco Dolstra
d5eab2fc82 * Use foreach in a lot of places. 2009-04-21 11:52:16 +00:00
Eelco Dolstra
5dd8fb2069 * Don't use ULLONG_MAX in maxFreed - use 0 to mean "no limit".
18446744073709551615ULL breaks on GCC 3.3.6 (`integer constant is
  too large for "long" type').
2009-03-26 11:02:07 +00:00
Eelco Dolstra
92cb7c4dfe * Put chroots in the Nix store. This ensures that we can create hard
links to the inputs.
2008-12-12 17:14:57 +00:00
Eelco Dolstra
0008b0006d * Simplify deleting .lock files in /nix/store: just don't delete them
if they belong a path that's currently being built.  This gets rid
  of some Cygwin-specific code.
2008-12-12 17:03:18 +00:00
Eelco Dolstra
f32fef1b07 * GC option `--max-atime' that specifies an upper limit to the last
accessed time of paths that may be deleted.  Anything more recently
  used won't be deleted.  The time is specified in time_t,
  e.g. seconds since 1970-01-01 00:00:00 UTC; use `date +%s' to
  convert to time_t from the command line. 

  Example: to delete everything that hasn't been used in the last two
  months:

  $ nix-store --gc -v --max-atime $(date +%s -d "2 months ago")
2008-09-17 14:52:35 +00:00
Eelco Dolstra
4af2fdba6d * Typo. 2008-09-17 13:00:55 +00:00
Eelco Dolstra
c987061aa4 * Some refactoring. Better output with `-v' for --use-atime. 2008-09-17 12:54:07 +00:00
Eelco Dolstra
7ab68961e4 * Garbage collector: added an option `--use-atime' to delete paths in
order of ascending last access time.  This is useful in conjunction
  with --max-freed or --max-links to prefer deleting non-recently used
  garbage, which is good (especially in the build farm) since garbage
  may become live again.

  The code could easily be modified to accept other criteria for
  ordering garbage by changing the comparison operator used by the
  priority queue in collectGarbage().
2008-09-17 10:02:55 +00:00
Eelco Dolstra
c03b729319 * Increase the sleep periods a bit to make the test less likely to
fail on slow machines.  Of course it would be better if this test
  wasn't timing dependent...
2008-08-14 09:26:30 +00:00
Eelco Dolstra
d3aa183beb * Garbage collector: option `--max-freed' to stop after at least N
bytes have been freed, `--max-links' to stop when the Nix store
  directory has fewer than N hard links (the latter being important
  for very large Nix stores on filesystems with a 32000 subdirectories
  limit).
2008-06-18 14:20:16 +00:00
Eelco Dolstra
a72709afd8 * Some refactoring: put the GC options / results in separate structs.
* The garbage collector now also prints the number of blocks freed.
2008-06-18 09:34:17 +00:00
Eelco Dolstra
94fd46fa1c * Note. 2008-06-14 16:02:31 +00:00
Eelco Dolstra
826b271d9a * Garbage collector: don't do a complete topological sort of the Nix
store under the reference relation, since that means that the
  garbage collector will need a long time to start deleting paths.
  Instead just delete the referrers of a path first.
2008-06-13 18:25:24 +00:00
Eelco Dolstra
30c9f909b2 * Print some progress info during the early GC stages. 2008-06-13 17:21:20 +00:00
Eelco Dolstra
b0e92f6d47 * Merged the no-bdb branch (-r10900:HEAD
https://svn.nixos.org/repos/nix/nix/branches/no-bdb).
2008-06-09 13:52:45 +00:00
Eelco Dolstra
633518628f * nix-env -e: support uninstalling by path, so that one can say
$ nix-env -e $(which firefox)

  or

    $ nix-env -e /nix/store/nywzlygrkfcgz7dfmhm5xixlx1l0m60v-pan-0.132

* nix-env -i: if an argument contains a slash anywhere, treat it as a
  path and follow it through symlinks into the Nix store.  This allows
  things like

    $ nix-build -A firefox
    $ nix-env -i ./result

* nix-env -q/-i/-e: don't complain when the `*' selector doesn't match
  anything.  In particular, `nix-env -q \*' doesn't fail anymore on an
  empty profile.
2007-11-29 16:18:24 +00:00
Eelco Dolstra
149e273023 * Don't need gc.hh. 2007-11-15 15:07:27 +00:00
Michael Raskin
6fc60e2060 Added possibility to specify garbage collection levels for store paths; so packages can share intermediate results of compilation and GC will collect it automatically while never touching tarballs, for example. 2007-11-15 03:47:12 +00:00
Eelco Dolstra
e0d7e47862 * PathLocks::lockPaths: don't allow reacquiring a lock we already
hold.
2007-08-28 09:39:03 +00:00
Eelco Dolstra
9e975458b4 * Get rid of the substitutes database table (NIX-47). Instead, if we
need any info on substitutable paths, we just call the substituters
  (such as download-using-manifests.pl) directly.  This means that
  it's no longer necessary for nix-pull to register substitutes or for
  nix-channel to clear them, which makes those operations much faster
  (NIX-95).  Also, we don't have to worry about keeping nix-pull
  manifests (in /nix/var/nix/manifests) and the database in sync with
  each other.

  The downside is that there is some overhead in calling an external
  program to get the substitutes info.  For instance, "nix-env -qas"
  takes a bit longer.

  Abolishing the substitutes table also makes the logic in
  local-store.cc simpler, as we don't need to store info for invalid
  paths.  On the downside, you cannot do things like "nix-store -qR"
  on a substitutable but invalid path (but nobody did that anyway).

* Never catch interrupts (the Interrupted exception).
2007-08-12 00:29:28 +00:00