Commit graph

1653 commits

Author SHA1 Message Date
Eelco Dolstra 8e3a7bd712 nix-store --verify: Add an option ‘--repair’ to repair all missing/corrupt paths
Also, return a non-zero exit code if errors remain after
verifying/repairing.
2012-10-02 15:12:56 -04:00
Eelco Dolstra 9958bd6992 Add operation ‘nix-store --repair-path’
This operation allows fixing corrupted or accidentally deleted store
paths by redownloading them using substituters, if available.

Since the corrupted path cannot be replaced atomically, there is a
very small time window (one system call) during which neither the old
(corrupted) nor the new (repaired) contents are available.  So
repairing should be used with some care on critical packages like
Glibc.
2012-10-02 14:08:59 -04:00
Eelco Dolstra e666e1156f Handle octal escapes in /proc/self/mountinfo 2012-09-28 21:39:30 -04:00
Eelco Dolstra f406288cc7 Print a more descriptive error message if setting up the build environment fails 2012-09-28 21:37:02 -04:00
Eelco Dolstra 95c74eae26 Allow dashes in identifiers
In Nixpkgs, the attribute in all-packages.nix corresponding to a
package is usually equal to the package name.  However, this doesn't
work if the package contains a dash, which is fairly common.  The
convention is to replace the dash with an underscore (e.g. "dbus-lib"
becomes "dbus_glib"), but that's annoying.  So now dashes are valid in
variable / attribute names, allowing you to write:

  dbus-glib = callPackage ../development/libraries/dbus-glib { };

and

  buildInputs = [ dbus-glib ];

Since we don't have a negation or subtraction operation in Nix, this
is unambiguous.
2012-09-27 15:49:20 -04:00
Eelco Dolstra d534f137f0 Make the store writable before creating /nix/store/.links 2012-09-25 16:30:08 -04:00
Eelco Dolstra e464b0247d Merge branch 'readonly-store' 2012-09-25 15:38:00 -04:00
Eelco Dolstra 28bf183d2d Include <sys/types.h> for off_t
Reported by "gio" on IRC.
2012-09-25 13:00:19 -04:00
Eelco Dolstra b9c2b4d5b4 Remove setting of the immutable bit
Using the immutable bit is problematic, especially in conjunction with
store optimisation.  For instance, if the garbage collector deletes a
file, it has to clear its immutable bit, but if the file has
additional hard links, we can't set the bit afterwards because we
don't know the remaining paths.

So now that we support having the entire Nix store as a read-only
mount, we may as well drop the immutable bit.  Unfortunately, we have
to keep the code to clear the immutable bit for backwards
compatibility.
2012-09-19 16:17:54 -04:00
Eelco Dolstra b9124a5c33 Support having /nix/store as a read-only bind mount
It turns out that the immutable bit doesn't work all that well.  A
better way is to make the entire Nix store a read-only bind mount,
i.e. by doing

  $ mount --bind /nix/store /nix/store
  $ mount -o remount,ro,bind /nix/store

(This would typically done in an early boot script, before anything
from /nix/store is used.)

Since Nix needs to be able to write to the Nix store, it now detects
if /nix/store is a read-only bind mount and then makes it writable in
a private mount namespace.
2012-09-19 15:45:29 -04:00
Eelco Dolstra 76e88871b2 Templatise tokenizeString() 2012-09-19 15:43:23 -04:00
Eelco Dolstra 00092b2d35 Keep build directory if not all expected outputs were produced
Fixes issue #123 in Nixpkgs.
2012-09-18 10:11:42 -04:00
Eelco Dolstra 9fd9dedf12 nix-env --delete-generations: Support --dry-run flag
Fixes #43.
2012-09-13 18:05:04 -04:00
Eelco Dolstra 8fbe96cb31 RemoteStore::connectToDaemon(): Set close-on-exec flag
This ensures that "nix-build --run-env" doesn't keep a connection to
the worker open, preventing it from exiting.
2012-09-13 14:46:37 -04:00
Eelco Dolstra e6e495649c Vacuum the SQLite DB after running the garbage collector 2012-09-13 14:33:41 -04:00
Eelco Dolstra 2923b55f9d Delete paths in a component in topologically sorted order
The outputs of a derivation can refer to each other (even though they
cannot have cycles), so they have to be deleted in the right order.

http://hydra.nixos.org/build/3026118
2012-09-13 13:08:27 -04:00
Eelco Dolstra 6c4ac29917 Disable auto store optimisation for now
I've seen operations like "nix-store --import" take much longer on one
system.  So default to off until I've investigated this a bit further.
2012-09-13 10:28:20 -04:00
Eelco Dolstra e56f71edaf In startBuilder(), only print the new paths we're building 2012-09-13 10:06:24 -04:00
Eelco Dolstra 4fca02077c Handle gc-keep-outputs and gc-keep-derivations both enabled
If the options gc-keep-outputs and gc-keep-derivations are both
enabled, you can get a cycle in the liveness graph.  There was a hack
to handle this, but it didn't work with multiple-output derivations,
causing the garbage collector to fail with errors like ‘error: cannot
delete path `...' because it is in use by `...'’.  The garbage
collector now handles strongly connected components in the liveness
graph as a unit and decides whether to delete all or none of the paths
in an SCC.
2012-09-12 18:49:35 -04:00
Eelco Dolstra 479e9172b3 Build hook: Pass the timeout to the remote builder
Note that this will only work if the client has a very recent Nix
version (post 15e1b2c223), otherwise the
--option flag will just be ignored.

Fixes #50.
2012-09-12 12:18:14 -04:00
Eelco Dolstra 5e2ffd0b8a Fix "non-zero padding" error
Probably it's not a good idea to pass a temporary object to
StringSource.
2012-09-11 19:09:01 -04:00
Eelco Dolstra 8cf672091e Support building a derivation if some outputs are already valid (non-chroot case)
This uses scary hash rewriting.

Fixes #21.
2012-09-11 18:39:22 -04:00
Eelco Dolstra 9dbda2b3fe Remove debug line 2012-09-11 17:05:35 -04:00
Eelco Dolstra a2785b7391 Support building a derivation if some outputs are already valid
This handles the chroot and build hook cases, which are easy.
Supporting the non-chroot-build case will require more work (hash
rewriting!).

Issue #21.
2012-09-11 16:59:59 -04:00
Eelco Dolstra 295027f533 Include config.h before any other header
"config.h" must be included first, because otherwise the compiler
might not see the right value of _FILE_OFFSET_BITS.  We've had this
before; see 705868a8a9.  In this case,
GCC would compute a different address for ‘settings.useSubstitutes’ in
misc.cc because of the off_t in ‘settings’.

Reverts 3854fc9b42.

http://hydra.nixos.org/build/3016700
2012-09-11 14:45:42 -04:00
Eelco Dolstra f7b650d234 Make "nix-instantiate -" interruptible 2012-08-28 11:47:26 -04:00
Eelco Dolstra cfd968dd94 Fix stupid type error in calling std::max 2012-08-27 14:17:13 -04:00
Eelco Dolstra e94806d030 Merge branch 'master' into no-manifests 2012-08-27 11:09:07 -04:00
Eelco Dolstra a9e6752bbd Include the output name in the GC root link
Output names are now appended to resulting GC symlinks, e.g. by
nix-build.  For backwards compatibility, if the output is named "out",
nothing is appended.  E.g. doing "nix-build -A foo" on a derivation
that produces outputs "out", "bin" and "dev" will produce symlinks
"./result", "./result-bin" and "./result-dev", respectively.
2012-08-24 16:58:11 -04:00
Eelco Dolstra 4aa1e5c554 Receive reserveSpace before calling startWork()
Otherwise we can get a SIGPOLL.  Reported by Ludovic.
2012-08-22 10:58:24 -04:00
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 767101824a Avoid concatenating lists of one string 2012-08-13 15:10:29 -04:00
Eelco Dolstra e5c589d271 Don't allocate empty lists
This saves about 4 MB when evaluating a NixOS system configuration.
2012-08-13 15:02:09 -04:00
Eelco Dolstra 3e89ef597c Optimise concatenating a list to an empty list
More precisely, in concatLists, if all lists except one are empty,
then just return the non-empty list.  This reduces the number of list
element allocations by 32% when evaluating a NixOS system
configuration.
2012-08-13 14:58:54 -04:00
Eelco Dolstra 9c2d63084b Add a primop ‘elemAt’ to get an element from a list 2012-08-13 13:46:42 -04:00
Eelco Dolstra 198d0338be Add a primop ‘concatLists’
This can serve as a generic efficient list builder.  For instance, the
function ‘catAttrs’ in Nixpkgs can be rewritten from

  attr: l: fold (s: l: if hasAttr attr s then [(getAttr attr s)] ++ l else l) [] l

to

  attr: l: builtins.concatLists (map (s: if hasAttr attr s then [(getAttr attr s)] else []) l)

Statistics before:

  time elapsed: 1.08683
  size of a value: 24
  environments allocated: 1384376 (35809568 bytes)
  list elements: 6946783 (55574264 bytes)
  list concatenations: 37434
  values allocated: 1760440 (42250560 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18273
  number of thunks: 1297673
  number of thunks avoided: 1380759
  number of attr lookups: 430802
  number of primop calls: 628912
  number of function calls: 1333544

Statistics after (including new catAttrs):

  time elapsed: 0.959854
  size of a value: 24
  environments allocated: 1010198 (26829296 bytes)
  list elements: 1984878 (15879024 bytes)
  list concatenations: 30488
  values allocated: 1589760 (38154240 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18274
  number of thunks: 1040925
  number of thunks avoided: 1038428
  number of attr lookups: 438419
  number of primop calls: 474844
  number of function calls: 959366
2012-08-13 01:53:10 -04:00
Eelco Dolstra b9e5b908ed Provide an efficient implementation of ‘elem’
The one in Nixpkgs is O(n^2), this one is O(n).  Big reduction in the
number of list allocations.

Statistics before (on a NixOS system config):

  time elapsed: 1.17982
  size of a value: 24
  environments allocated: 1543334 (39624560 bytes)
  list elements: 9612638 (76901104 bytes)
  list concatenations: 37434
  values allocated: 1854933 (44518392 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18272
  number of thunks: 1392467
  number of thunks avoided: 1507311
  number of attr lookups: 430801
  number of primop calls: 691600
  number of function calls: 1492502

Statistics after:

  time elapsed: 1.08683
  size of a value: 24
  environments allocated: 1384376 (35809568 bytes)
  list elements: 6946783 (55574264 bytes)
  list concatenations: 37434
  values allocated: 1760440 (42250560 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18273
  number of thunks: 1297673
  number of thunks avoided: 1380759
  number of attr lookups: 430802
  number of primop calls: 628912
  number of function calls: 1333544
2012-08-13 01:05:35 -04:00
Eelco Dolstra 4ccd48ce24 Add a "filter" primop
Evaluation of a NixOS configuration spends quite a lot of time in the
"filter" function in Nixpkgs.  As implemented in Nixpkgs, this is a
O(n^2) operation, so it's a good candidate for providing a more
efficient (i.e. primop) implementation.  Using it gives a ~10% speed
increase and a significant reduction in the number of evaluations.

Statistics before (on a NixOS system config):

  time elapsed: 1.3258
  size of a value: 24
  environments allocated: 1980939 (50127080 bytes)
  list elements: 14679308 (117434464 bytes)
  list concatenations: 50828
  values allocated: 2098938 (50374512 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18271
  number of thunks: 1645752
  number of thunks avoided: 1921196
  number of attr lookups: 430798
  number of primop calls: 838807
  number of function calls: 1930107

Statistics after:

  time elapsed: 1.17982
  size of a value: 24
  environments allocated: 1543334 (39624560 bytes)
  list elements: 9612638 (76901104 bytes)
  list concatenations: 37434
  values allocated: 1854933 (44518392 bytes)
  attribute sets allocated: 392040
  right-biased unions: 186334
  values copied in right-biased unions: 591137
  symbols in symbol table: 18272
  number of thunks: 1392467
  number of thunks avoided: 1507311
  number of attr lookups: 430801
  number of primop calls: 691600
  number of function calls: 1492502
2012-08-13 00:28:08 -04:00
Eelco Dolstra 62f72eb9e1 Add some more evaluations stats 2012-08-12 23:41:48 -04:00
Eelco Dolstra e82767910c Add some basic profiling support to the evaluator
Setting the environment variable NIX_COUNT_CALLS to 1 enables some
basic profiling in the evaluator.  It will count calls to functions
and primops as well as evaluations of attributes.

For example, to see where evaluation of a NixOS configuration spends
its time:

$ NIX_SHOW_STATS=1 NIX_COUNT_CALLS=1 ./src/nix-instantiate/nix-instantiate '<nixos>' -A system --readonly-mode
...
calls to 39 primops:
    239532 head
    233962 tail
    191252 hasAttr
...
calls to 1595 functions:
    224157 `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/pkgs/lib/lists.nix:17:19'
    221767 `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/pkgs/lib/lists.nix:17:14'
    221767 `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/pkgs/lib/lists.nix:17:10'
...
evaluations of 7088 attributes:
    167377 undefined position
    132459 `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/pkgs/lib/attrsets.nix:119:41'
     47322 `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/pkgs/lib/attrsets.nix:13:21'
...
2012-08-12 23:29:28 -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