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136 commits

Author SHA1 Message Date
Eelco Dolstra 11800e6198 download-from-binary-cache: parallelise fetching of NAR info files
Getting substitute information using the binary cache substituter has
non-trivial latency overhead.  A package or NixOS system configuration
can have hundreds of dependencies, and in the worst case (when the
local info cache is empty) we have to do a separate HTTP request for
each of these.  If the ping time to the server is t, getting N info
files will take tN seconds; e.g., with a ping time of 0.1s to
nixos.org, sequentially downloading 1000 info files (a typical NixOS
config) will take at least 100 seconds.

To fix this problem, the binary cache substituter can now perform
requests in parallel.  This required changing the substituter
interface to support a function querySubstitutablePathInfos() that
queries multiple paths at the same time, and rewriting queryMissing()
to take advantage of parallelism.  (Due to local caching,
parallelising queryMissing() is sufficient for most use cases, since
it's almost always called before building a derivation and thus fills
the local info cache.)

For example, parallelism speeds up querying all 1056 paths in a
particular NixOS system configuration from 116s to 2.6s.  It works so
well because the eccentricity of the top-level derivation in the
dependency graph is only 9.  So we only need 10 round-trips (when
using an unlimited number of parallel connections) to get everything.

Currently we do a maximum of 150 parallel connections to the server.
Thus it's important that the binary cache server (e.g. nixos.org) has
a high connection limit.  Alternatively we could use HTTP pipelining,
but WWW::Curl doesn't support it and libcurl has a hard-coded limit of
5 requests per pipeline.
2012-07-06 19:08:20 -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 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 194d21f9f6 * Sync with the trunk. 2011-12-16 23:33:01 +00:00
Eelco Dolstra 273b288a7e * importPath() -> importPaths(). Because of buffering of the input
stream it's now necessary for the daemon to process the entire
  sequence of exported paths, rather than letting the client do it.
2011-12-16 22:31:25 +00:00
Shea Levy af2e53fd48 Include all outputs of derivations in the closure of explicitly-passed derivation paths
This required adding a queryOutputDerivationNames function in the store API
2011-11-06 06:28:20 +00:00
Eelco Dolstra a3883cbd28 * Store the size of a store path in the database (to be precise, the
size of the NAR serialisation of the path, i.e., `nix-store --dump
  PATH').  This is useful for Hydra.
2010-11-16 17:11:46 +00:00
Eelco Dolstra f92c9a0ac5 * Allow unprivileged users to do `nix-store --clear-failed-paths' and
`nix-store --query-failed-paths'.
2010-05-04 10:45:10 +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 07cdfb09fb * Open the connection to the daemon lazily (on demand) so that
read-only operations (like nix-env -qa) work properly when the
  daemon isn't running.
2008-12-11 14:30:25 +00:00
Eelco Dolstra ff762fb499 * Pass HashType values instead of strings. 2008-12-03 16:10:17 +00:00
Eelco Dolstra 64519cfd65 * Unify the treatment of sources copied to the store, and recursive
SHA-256 outputs of fixed-output derivations.  I.e. they now produce
  the same store path:

  $ nix-store --add x
  /nix/store/j2fq9qxvvxgqymvpszhs773ncci45xsj-x

  $ nix-store --add-fixed --recursive sha256 x
  /nix/store/j2fq9qxvvxgqymvpszhs773ncci45xsj-x

  the latter being the same as the path that a derivation

    derivation {
      name = "x";
      outputHashAlgo = "sha256";
      outputHashMode = "recursive";
      outputHash = "...";
      ...
    };

  produces.

  This does change the output path for such fixed-output derivations.
  Fortunately they are quite rare.  The most common use is fetchsvn
  calls with SHA-256 hashes.  (There are a handful of those is
  Nixpkgs, mostly unstable development packages.)
  
* Documented the computation of store paths (in store-api.cc).
2008-12-03 15:06:30 +00:00
Eelco Dolstra 3c92ea399d * Make nix-env --dry-run print the paths to be substituted correctly
again.  (After the previous substituter mechanism refactoring I
  didn't update the code that obtains the references of substitutable
  paths.)  This required some refactoring: the substituter programs
  are now kept running and receive/respond to info requests via
  stdin/stdout.
2008-08-02 12:54:35 +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 66c51dc215 * nix-store --dump-db / --load-db to dump/load the Nix DB.
* nix-store --register-validity: option to supply the content hash of
  each path.
* Removed compatibility with Nix <= 0.7 stores.
2008-01-29 18:17:36 +00:00
Eelco Dolstra c370755583 * Flag `--no-build-hook' to disable distributed builds.
* queryDeriver in daemon mode: don't barf if the other side returns an
  empty string (which means there is no deriver).
2007-11-16 16:15:26 +00:00
Eelco Dolstra f3441e6122 * Pass various options to the worker so that flags like -K or -j work
in multi-user Nix (NIX-72).
* Client/worker: exchange a protocol version number for future
  compatibility.
2007-09-18 09:11:20 +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
Eelco Dolstra 6d1a1191b0 * Support queryDeriver() in multi-user installations. 2007-06-12 16:53:44 +00:00
Eelco Dolstra bdadb98de8 * `nix-store --import' now also works in remote mode. The worker
always requires a signature on the archive.  This is to ensure that
  unprivileged users cannot add Trojan horses to the Nix store.
2007-02-21 17:34:02 +00:00
Eelco Dolstra 0f5da8a83c * Support exportPath() in remote mode. 2007-02-21 16:34:00 +00:00
Eelco Dolstra 43c4d18c6a * nix-store --import': import an archive created by nix-store
--export' into the Nix store, and optionally check the cryptographic
  signatures against /nix/etc/nix/signing-key.pub.  (TODO: verify
  against a set of public keys.)
2007-02-21 15:45:32 +00:00
Eelco Dolstra b824a1daee * Start of `nix-store --export' operation for serialising a store
path.  This is like `nix-store --dump', only it also dumps the
  meta-information of the store path (references, deriver).  Will add
  a `--sign' flag later to add a cryptographic signature, which we
  will use for exchanging store paths between build farm machines in a
  secure manner.
2007-02-20 23:17:20 +00:00
Eelco Dolstra a3e6415ba8 * New primop builtins.filterSource, which can be used to filter files
from a source directory.  All files for which a predicate function
  returns true are copied to the store.  Typical example is to leave
  out the .svn directory:

    stdenv.mkDerivation {
      ...
      src = builtins.filterSource
        (path: baseNameOf (toString path) != ".svn")
        ./source-dir;
      # as opposed to
      #   src = ./source-dir;
    }

  This is important because the .svn directory influences the hash in
  a rather unpredictable and variable way.
2006-12-12 23:05:01 +00:00
Eelco Dolstra a9c4f66cfb * Allow unprivileged users to run the garbage collector and to do
`nix-store --delete'.  But unprivileged users are not allowed to
  ignore liveness.
* `nix-store --delete --ignore-liveness': ignore the runtime roots as
  well.
2006-12-05 02:18:46 +00:00
Eelco Dolstra 29cf434a35 * The determination of the root set should be made by the privileged
process, so forward the operation.
* Spam the user about GC misconfigurations (NIX-71).
* findRoots: skip all roots that are unreadable - the warnings with
  which we spam the user should be enough.
2006-12-05 01:31:45 +00:00
Eelco Dolstra 74033a844f * Add indirect root registration to the protocol so that unprivileged
processes can register indirect roots.  Of course, there is still
  the problem that the garbage collector can only read the targets of
  the indirect roots when it's running as root...
2006-12-04 23:29:16 +00:00
Eelco Dolstra 4740baf3a6 * When NIX_REMOTE=daemon, connect to /nix/var/nix/daemon.socket
instead of forking a worker.
2006-12-04 14:21:39 +00:00
Eelco Dolstra f5f0cf423f * Refactoring. 2006-12-04 13:28:14 +00:00
Eelco Dolstra 4251f94b32 * Use a Unix domain socket instead of pipes. 2006-12-03 02:36:44 +00:00
Eelco Dolstra 7951c3c546 * Some hackery to propagate the worker's stderr and exceptions to the
client.
2006-12-03 02:08:13 +00:00
Eelco Dolstra e25fad691a * Move addTempRoot() to the store API, and add another function
syncWithGC() to allow clients to register GC roots without needing
  write access to the global roots directory or the GC lock.
2006-12-02 16:41:36 +00:00
Eelco Dolstra a824d58b56 * Merge addToStore and addToStoreFixed.
* addToStore now adds unconditionally, it doesn't use readOnlyMode.
  Read-only operation is up to the caller (who can call
  computeStorePathForPath).
2006-12-01 20:51:18 +00:00
Eelco Dolstra 0565b5f2b3 * More remote operations.
* Added new operation hasSubstitutes(), which is more efficient than
  querySubstitutes().size() > 0.
2006-11-30 22:43:55 +00:00
Eelco Dolstra 765bdfe542 * When NIX_REMOTE is set to "slave", fork off nix-worker in slave
mode.  Presumably nix-worker would be setuid to the Nix store user.
  The worker performs all operations on the Nix store and database, so
  the caller can be completely unprivileged.

  This is already much more secure than the old setuid scheme, since
  the worker doesn't need to do Nix expression evaluation and so on.
  Most importantly, this means that it doesn't need to access any user
  files, with all resulting security risks; it only performs pure
  store operations.

  Once this works, it is easy to move to a daemon model that forks off
  a worker for connections established through a Unix domain socket.
  That would be even more secure.
2006-11-30 19:54:43 +00:00
Eelco Dolstra 9adc074dc3 * Oops. 2006-11-30 18:35:50 +00:00