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2010-02-03 * Revert r19797, and use a simpler solution: just don't monitor buildEelco Dolstra1-12/+2
hooks for silence. It's unnecessary because the remote nix-store command is already monitoring the real build.
2010-02-03 * While waiting for a lock, print a sign of life every 5 minutes.Eelco Dolstra1-2/+12
This prevents remote builders from being killed by the `max-silent-time' inactivity monitor while they are waiting for a long garbage collection to finish. This happens fairly often in the Hydra build farm.
2010-02-02 * Remove most Cygwin-specific code. Cygwin 1.7 implements advisoryEelco Dolstra1-58/+3
POSIX locks, and simulates Unix-style file deletion semantics sufficiently. Note that this means that Nix won't work on Cygwin 1.5 anymore.
2009-04-21 * Use foreach in a lot of places.Eelco Dolstra1-2/+2
2009-03-23 * No longer block while waiting for a lock on a store path. InsteadEelco Dolstra1-4/+13
poll for it (i.e. if we can't acquire the lock, then let the main select() loop wait for at most a few seconds and then try again). This improves parallelism: if two nix-store processes are both trying to build a path at the same time, the second one shouldn't block; it should first see if it can build other goals. Also, it prevents the deadlocks that have been occuring in Hydra lately, where a process waits for a lock held by another process that's waiting for a lock held by the first. The downside is that polling isn't really elegant, but POSIX doesn't provide a way to wait for locks in a select() loop. The only solution would be to spawn a thread for each lock to do a blocking fcntl() and then signal the main thread, but that would require pthreads.
2009-02-16 * Release output locks as soon as possible, not when the destructor ofEelco Dolstra1-0/+8
the DerivationGoal runs. Otherwise, if a goal is a top-level goal, then the lock won't be released until nix-store finishes. With --keep-going and lots of top-level goals, it's possible to run out of file descriptors (this happened sometimes in the build farm for Nixpkgs). Also, for failed derivation, it won't be possible to build it again until the lock is released. * Idem for locks on build users: these weren't released in a timely manner for failed top-level derivation goals. So if there were more than (say) 10 such failed builds, you would get an error about having run out of build users.
2008-05-21 * GCC 4.3.0 (Fedora 9) compatibility fixes. Reported by Gour andEelco Dolstra1-0/+1
Armijn Hemel.
2007-08-28 * Fix a race condition with parallel builds where multipleEelco Dolstra1-0/+7
fixed-output derivations or substitutions try to build the same store path at the same time. Locking generally catches this, but not between multiple goals in the same process. This happened especially often (actually, only) in the build farm with fetchurl downloads of the same file being executed on multiple machines and then copied back to the main machine where they would clobber each other (NIXBF-13). Solution: if a goal notices that the output path is already locked, then go to sleep until another goal finishes (hopefully the one locking the path) and try again.
2007-08-28 * PathLocks::lockPaths: don't allow reacquiring a lock we alreadyEelco Dolstra1-4/+2
hold.
2006-09-04 * Use a proper namespace.Eelco Dolstra1-2/+9
* Optimise header file usage a bit. * Compile the parser as C++.
2006-06-20 * Concurrent GC on Cygwin.Eelco Dolstra1-50/+79
2006-06-19 * On Windows we cannot delete open (lock) files, so we delete lockEelco Dolstra1-4/+47
files after we've closed them. Since this only succeeds if the lock is no longer opened by any process, the token trick used on Unix is not necessary.
2006-06-15 * In `nix-env -i|-u|-e', lock the profile to prevent races betweenEelco Dolstra1-4/+7
concurrent nix-env operations on the same profile. Fixes NIX-7.
2005-01-31 * Don't delete active lock files.Eelco Dolstra1-3/+2
2005-01-27 * Make lock removal safe by signalling to blocked processes that theEelco Dolstra1-22/+43
lock they are waiting on has become stale (we do this by writing a meaningless token to the unlinked file).
2004-05-11 * True parallel builds. Nix can now run as many build jobs inEelco Dolstra1-2/+20
parallel as possible (similar to GNU Make's `-j' switch). This is useful on SMP systems, but it is especially useful for doing builds on multiple machines. The idea is that a large derivation is initiated on one master machine, which then distributes sub-derivations to any number of slave machines. This should not happen synchronously or in lock-step, so the master must be capable of dealing with multiple parallel build jobs. We now have the infrastructure to support this. TODO: substitutes are currently broken.
2004-01-15 * Catch SIGINT to terminate cleanly when the user tries to interruptEelco Dolstra1-1/+6
Nix. This is to prevent Berkeley DB from becoming wedged. Unfortunately it is not possible to throw C++ exceptions from a signal handler. In fact, you can't do much of anything except change variables of type `volatile sig_atomic_t'. So we set an interrupt flag in the signal handler and check it at various strategic locations in the code (by calling checkInterrupt()). Since this is unlikely to cover all cases (e.g., (semi-)infinite loops), sometimes SIGTERM may now be required to kill Nix.
2003-12-21 * Bug fix: parallel builds of the same derivation failed due to lock file ↵Eelco Dolstra1-3/+5
removal.
2003-11-21 * Remove lock files after building. Eelco Dolstra1-1/+13
2003-11-18 * libnix -> libstore.Eelco Dolstra1-0/+90