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16 commits

Author SHA1 Message Date
Eelco Dolstra 863dcff6c5 * Started removing closure store expressions, i.e., the explicit
representation of closures as ATerms in the Nix store.  Instead, the
  file system pointer graph is now stored in the Nix database.  This
  has many advantages:

  - It greatly simplifies the implementation (we can drop the notion
    of `successors', and so on).

  - It makes registering roots for the garbage collector much easier.
    Instead of specifying the closure expression as a root, you can
    simply specify the store path that must be retained as a root.
    This could not be done previously, since there was no way to find
    the closure store expression containing a given store path.
    
  - Better traceability: it is now possible to query what paths are
    referenced by a path, and what paths refer to a path.
2005-01-19 11:16:11 +00:00
Eelco Dolstra fa9259f5f5 * Simplify the substitute mechanism:
- Drop the store expression.  So now a substitute is just a
    command-line invocation (a program name + arguments).  If you
    register a substitute you are responsible for registering the
    expression that built it (if any) as a root of the garbage
    collector.
  - Drop the substitutes-rev DB table.
2004-12-20 13:43:32 +00:00
Eelco Dolstra dcc433de47 * Operation `--delete-generations' to delete generations of a
profile.  Arguments are either generation number, or `old' to delete
  all non-current generations.  Typical use:

  $ nix-env --delete-generations old
  $ nix-collect-garbage

* istringstream -> string2Int.
2004-09-10 13:32:08 +00:00
Eelco Dolstra 5c443b6550 * Main the `substitutes-rev' table again, but now in a way that
doesn't take \Theta(n^2) space/time complexity.
2004-08-31 16:13:10 +00:00
Eelco Dolstra eb233e728f * `--min-age' flag in nix-store and nix-collect-garbage to only delete
unreachable paths that haven't been used for N hours.  For instance,
  `nix-collect-garbage --min-age 168' only deletes paths that haven't
  been accessed in the last week.

  This is useful for instance in the build farm where many derivations
  can be shared between consecutive builds, and we wouldn't want a
  garbage collect to throw them all away.  We could of course register
  them as roots, but then we'd to unregister them at some point, which
  would be a pain to manage.  The `--min-age' flag gives us a sort of
  MRU caching scheme.

  BUG: this really shouldn't be in gc.cc since that violates
  mechanism/policy separation.
2004-08-25 16:54:08 +00:00
Eelco Dolstra fdec72c6cc * `nix-collect-garbage' now actually performs a garbage collection, it
doesn't just print the set of paths that should be deleted.  So
  there is no more need to pipe the result into `nix-store --delete'
  (which doesn't even exist anymore).
2004-08-25 15:39:13 +00:00
Eelco Dolstra 818047881e * Put the garbage collector in nix-store: operation `--gc',
suboperations `--print-live', `--print-dead', and `--delete'.  The
  roots are not determined by nix-store; they are read from standard
  input.  This is to make it easy to customise what the roots are.

  The collector now no longer fails when store expressions are missing
  (which legally happens when using substitutes).  It never tries to
  fetch paths through substitutes.

  TODO: acquire a global lock on the store while garbage collecting.
  
* Removed `nix-store --delete'.
2004-08-25 11:43:49 +00:00
Eelco Dolstra 91dc023665 * Added a switch `--fallback'. From the manual:
Whenever Nix attempts to realise a derivation for which a closure is
  already known, but this closure cannot be realised, fall back on
  normalising the derivation.

  The most common scenario in which this is useful is when we have
  registered substitutes in order to perform binary distribution from,
  say, a network repository.  If the repository is down, the
  realisation of the derivation will fail.  When this option is
  specified, Nix will build the derivation instead.  Thus, binary
  installation falls back on a source installation.  This option is
  not the default since it is generally not desirable for a transient
  failure in obtaining the substitutes to lead to a full build from
  source (with the related consumption of resources).
2004-06-28 10:42:57 +00:00
Eelco Dolstra 2db9748221 * Remove debug output. 2004-06-21 10:01:17 +00:00
Eelco Dolstra daf0a923c7 * Wrap calls to registerSubstitute() in a single transaction to
improve throughput.
* Don't build the `substitute-rev' table for now, since it caused
  Theta(N^2) time and log file consumption when adding N substitutes.
  Maybe we can do without it.
2004-06-21 07:38:17 +00:00
Eelco Dolstra 112ee89501 * Re-enable support for substitutes in the normaliser.
* A better substitute mechanism.

  Instead of generating a store expression for each store path for
  which we have a substitute, we can have a single store expression
  that builds a generic program that is invoked to build the desired
  store path, which is passed as an argument.

  This means that operations like `nix-pull' only produce O(1) files
  instead of O(N) files in the store when registering N substitutes.
  (It consumes O(N) database storage, of course, but that's not a
  performance problem).

* Added a test for the substitute mechanism.
  
* `nix-store --substitute' reads the substitutes from standard input,
  instead of from the command line.  This prevents us from running
  into the kernel's limit on command line length.
2004-06-20 19:17:54 +00:00
Eelco Dolstra 76c0e85929 * The environment variable NIX_ROOT can now be set to execute Nix in a
chroot() environment.
* A operation `--validpath' to register path validity.  Useful for
  bootstrapping in a pure Nix environment.
* Safety checks: ensure that files involved in store operations are in
  the store.
2004-02-14 21:44:18 +00:00
Eelco Dolstra 46a71c857c * Option --force-realise' in nix-store --query'. 2004-01-09 14:18:28 +00:00
Eelco Dolstra 078e20885e * Help text for all (non-script) programs, so no more:
$ nix-instantiate --help
error: unknown flag `--help`
Try `nix-instantiate --help' for more information.

:-)
2003-12-01 15:55:05 +00:00
Eelco Dolstra 9898746ef3 * nix-env: a tool to manage user environments.
* Replace all directory reading code by a generic readDirectory()
  function.
2003-11-19 17:27:16 +00:00
Eelco Dolstra dfc9c64ead * "Fix expression" -> "Nix expression".
* More refactoring.
2003-11-18 12:06:07 +00:00
Renamed from src/nix-store/nix.cc (Browse further)