So we received a report that the thread pool crashed due to an
Interrupted exception.
Relevant log tail:
copying path '/nix/store/0kal2k73inviikxv9f1ciaj39lkl9a87-etc-os-release' to 'ssh://192.168.0.27'...
Lix crashed. This is a bug. We would appreciate if you report it along with what caused it at https://git.lix.systems/lix-project/lix/issues with the following information included:
error (ignored): error: interrupted by the user
Exception: nix::Interrupted: error: interrupted by the user
Relevant stack trace:
4# __cxa_rethrow in /nix/store/22nxhmsfcv2q2rpkmfvzwg2w5z1l231z-gcc-13.3.0-lib/lib/libstdc++.so.6
5# nix::ignoreExceptionExceptInterrupt(nix::Verbosity) in /nix/store/ghxr2ykqc3rrfcy8rzdys0rzx9ah5fqj-lix-2.92.0-dev-pre20241005-ed9b7f4/lib/liblixutil.so
6# nix::ThreadPool::doWork(bool) in /nix/store/ghxr2ykqc3rrfcy8rzdys0rzx9ah5fqj-lix-2.92.0-dev-pre20241005-ed9b7f4/lib/liblixutil.so
7# 0x00007FA7A00E86D3 in /nix/store/22nxhmsfcv2q2rpkmfvzwg2w5z1l231z-gcc-13.3.0-lib/lib/libstdc++.so.6
8# 0x00007FA79FE99A42 in /nix/store/3dyw8dzj9ab4m8hv5dpyx7zii8d0w6fi-glibc-2.39-52/lib/libc.so.6
9# 0x00007FA79FF1905C in /nix/store/3dyw8dzj9ab4m8hv5dpyx7zii8d0w6fi-glibc-2.39-52/lib/libc.so.6
Notably, this is *not* in the main thread, so this implies that the
thread didn't get joined properly before their destructors got called.
That, in turn, should have only possibly happened because join() threw
on a previous iteration of the loop joining threads, I think. Or if it
threw while in the ThreadPool destructor. Either way we had better stop
letting Interrupted fall out of our child threads!
If:
- Interrupted was thrown inside the action in the main thread: it would
have fallen out of doWork if state->exception was already set and got
caught by ThreadPool::process, calling shutdown() and the join loop
which would crash the process entirely.
- Interrupted was thrown inside the action on a secondary thread: it
would have been caught and put into the exception field and then
possibly rethrown to fall out of the thread (since it was previously
ignoreExceptionExceptInterrupt).
The one possible hole in this hypothesis is that there is an "error
(ignored)" line in there implying that at least one Interrupted got
eaten by an ignoreExceptionInDestructor. It's also unclear whether this
got reordered because of stderr buffering.
Fixes: #542
Change-Id: I322cf050da660af78f5cb0e08ec6e6d27d09ac76
I followed @pennae's advice and moved the constructor definition of
`AttrName` from the header file `nixexpr.hh` to `nixexpr.cc`.
Change-Id: I733f56c25635b366b11ba332ccec38dd7444e793
The approach that was taken here was to add default values to the type
definitions rather than specify them whenever they are missing.
Now the only remaining warning is '-Wunused-parameter' which @jade said
is usually counterproductive and that we can just disable it:
#456 (comment)
So this change adds the flags '-Wall', '-Wextra' and
'-Wno-unused-parameter', so that all warnings are enabled except for
'-Wunused-parameter'.
Change-Id: Ic223a964d67ab429e8da804c0721ba5e25d53012
There was a bug report about a potential call to `memcpy` with a null
pointer which is not reproducible:
#492
This occurred in `src/libstore/filetransfer.cc` in `InnerSource::read`.
To ensure that this doesn't happen, an early return is added before
calling `memcpy` if the length of the data to be copied is 0.
This change also adds a test that ensures that when `InnerSource::read`
is called with an empty file, it throws an `EndOfFile` exception.
Change-Id: Ia18149bee9a3488576c864f28475a3a0c9eadfbb
these two functions are now nearly trivial and much better inline into
makeGoalCommon. keeping them separate also separates information about
goal completion flows and how failure information ends up in `Worker`.
Change-Id: I6af86996e4a2346583371186595e3013c88fb082
we can use our newfound powers of Goal::work Is A Real Promise to remove
completed goals from continuation promises. apart from being much easier
to follow it's also a lot more efficient because we have the iterator to
the item we are trying to remove, skipping a linear search of the cache.
Change-Id: Ie0190d051c5f4b81304d98db478348b20c209df5
Goal::work() is a fully usable promise that does not rely on the worker
to report completion conditions. as such we no longer need the `notify`
field that enabled this interplay. we do have to clear goal caches when
destroying the worker though, otherwise goal promises may (incorrectly)
keep goals alive due to strong shared pointers created by childStarted.
Change-Id: Ie607209aafec064dbdf3464fe207d70ba9ee158a
derivation goals still hold a BuildResult member variable since parts of
these results of accumulated in different places, but the Goal class now
no longer has such a field. substitution goals don't need it at all, and
derivation goals should also be refactored to not drop their buildResult
Change-Id: Ic6d3d471cdbe790a6e09a43445e25bedec6ed446
the field is simply duplicated between the two, and now that we can
return WorkResults from Worker::run we no longer need both of them.
Change-Id: I82fc47d050b39b7bb7d1656445630d271f6c9830
this will be needed to move all interesting result fields out of Goal
proper and into WorkResult. once that is done we can treat goals as a
totally internal construct of the worker mechanism, which also allows
us to fully stop exposing unclear intermediate state to Worker users.
Change-Id: I98d7778a4b5b2590b7b070bdfc164a22a0ef7190
since we now propagate goal exceptions properly we no longer need to
check topGoals for a reason to abort early. any early abort reasons,
whether by exception or a clean top goal failure, can now be handled
by inspecting the goal result in the main loop. this greatly reduces
goal-to-goal interactions that do not happen at the main loop level.
since the underscore-free name is now available for use as variables
we'll migrate to that where we currently use `_topGoals` for locals.
Change-Id: I5727c5ea7799647c0a69ab76975b1a03a6558aa6
drop childException since it's no longer needed. also makes
waitForInput, childFinished, and childTerminated redundant.
Change-Id: I05d88ffd323c5b5c909ac21056162f69ffb0eb9f
there's no reason to have the worker set information on goals that the
goals themselves return from their entry point. doing this in the goal
`work()` function is much cleaner, and a prerequisite to removing more
implicit strong shared references to goals that are currently running.
Change-Id: Ibb3e953ab8482a6a21ce2ed659d5023a991e7923
this simplifies the worker loop, and lets us remove it entirely later.
note that ideally only one promise waiting for interrupts should exist
in the entire system. not one per event loop, one per *process*. extra
interrupt waiters make interrupt response nondeterministic and as such
aren't great for user experience. if anything wants to react to aborts
caused by explicit interruptions, or anything else, those things would
be much better served using RAII guards such as Finally (or KJ_DEFER).
Change-Id: I41d035ff40172d536e098153c7375b0972110d51
this was a triumph. i'm making a note here: huge success. it's hard to
overstate my satisfaction! i'm not even angry. i'm being so sincere ri
actually, no. we *are* angry. this was one dumbass odyssey. nobody has
asked for this. but not doing it would have locked us into old, broken
protocols forever or (possibly worse) forced us to write our own async
framework building on the old did-you-mean-continuations in Worker. if
we had done that we'd be locked into ever more, and ever more complex,
manual state management all over the place. this just could not stand.
Change-Id: I43a6de1035febff59d2eff83be9ad52af4659871
with async runtime scheduling we can no longer guarantee exact error
counts for builds that do not set keepGoing. the old behavior can be
recovered with a number of hacks that affect scheduling, but none of
those are very easy to follow now advisable. exact error counts will
like not be needed for almost all uses except tests, and *those* had
better check the actual messages rather than how many they got. more
messages can even help to avoid unnecessary rebuilds for most users.
Change-Id: I1c9aa7a401227dcaf2e19975b8cb83c5d4f85d64
In 0e6b3435a1, installation of the HTML manual
was accidentally dropped: setting install_dir on a custom_target only sets the
directory where something is going to be installed if it is installed at all,
but does not itself trigger installation. The latter has to be explicitly
requested, which is just what we do here to get the manual back.
Change-Id: Iff8b791de7e7cb4c8d747c2a9b1154b5fcc32fe0
The test suite can load the global configuration files under certain
circumstances, and, though we would really rather it didn't ever do that
at all, we should at least break the mechanism.
Fixes: #474
Change-Id: Ib27cb43dd5dfaa70ac491c395b5ba308fd7bd289
due to event loop scheduling behavior it's possible for a derivation
goal to fully finish (having seen all paths it was asked to create),
but to not notify the worker of this in time to prevent another goal
asking the recently-finished goal for more outputs. if this happened
the finished goal would ignore the request for more outputs since it
considered itself fully done, and the delayed result reporting would
cause the requesting goal to assume its request had been honored. if
the requested goal had finished *properly* the worker would recreate
it instead of asking for more outputs, and this would succeed. it is
thus safe to always recreate goals once they are done, so we now do.
Change-Id: Ifedd69ca153372c623abe9a9b49cd1523588814f
This moves the "legacy"/"nix2" commands under a new `src/legacy/`
directory, instead of being scattered around in a bunch of different
directories.
A new `liblegacy` build target is defined, and the `nix` binary is
linked against it.
Then, `RegisterLegacyCommand` is replaced with `LegacyCommand::add`
calls in functions like `registerNixCollectGarbage()`. These
registration functions are called explicitly in `src/nix/main.cc`.
See: #359
Change-Id: Id450ffc3f793374907599cfcc121863b792aac1a
we'll now loop to update displayed statistics, and use this loop to
limit the update rate to 50 times per second. we could have updated
much more frequently before this (once per iteration of `runImpl`),
much faster than would ever be useful in practice. aggressive stats
updates can even impede progress due to terminal or network delays.
Change-Id: Ifba755a2569f73c919b1fbb06a142c0951395d6d
Worker::run() is now entirely based on the kj event loop and promises,
so we need not handle awakeness of goals manually any more. every goal
can instead, once it has finished a partial work call, defer itself to
being called again in the next iteration of the loop. same end effect.
Change-Id: I320eee2fa60bcebaabd74d1323fa96d1402c1d15
notably we will check whether we want to do GC at all only once during
startup, and we'll only attempt GC every ten seconds rather than every
time a goal has finished a partial work call. this shouldn't cause any
problems in practice since relying on auto-gc is not deterministic and
stores in which builds can fill all remaining free space in merely ten
seconds are severely troubled even when gargage collection runs a lot.
Change-Id: I1175a56bf7f4e531f8be90157ad88750ff2ddec4
Revert submission 1946
Reason for revert: regression in building (found via bisection)
Reported by users:
> error: path '/nix/store/04ca5xwvasz6s3jg0k7njz6rzi0d225w-jq-1.7.1-dev' does not exist in the store
Reverted changes: /q/submissionid:1946
Change-Id: I6f1a4b2f7d7ef5ca430e477fc32bca62fd97036b
nothing needs to signal being still active but not actively pollable,
only that immediate polling for the next goal work phase is in order.
Change-Id: Ia43c1015e94ba4f5f6b9cb92943da608c4a01555
this was immensely inefficient on large caches, as can exist when many
derivations are buildable simultaneously. since we have smart pointers
to goals we can do cache maintenance in goal deleters instead, and use
the exact iterators instead of doing a linear search. this *does* rely
on goals being deleted to remove them from the cache, which isn't true
for toplevel goals. those would have previously been removed when done
in all cases, removing the cache entry when keep-going is set. this is
arguably incorrect since it might result in those goals being retried,
although that could only happen with dynamic derivations or the likes.
(luckily dynamic derivations not complete enough to allow this at all)
Change-Id: I8e750b868393588c33e4829333d370f2c509ce99
makeDerivationGoalCommon had the right idea, but it didn't quite go far
enough. let's do the rest and remove the remaining factory duplication.
Change-Id: I1fe32446bdfb501e81df56226fd962f85720725b
this was a debugging aid from day one that should not have any impact on
build semantics, and if it *does* have an impact on build semantics then
build semantics are seriously broken. keeping the order imposed by these
keys will be impossible once we let a real event loop schedule our jobs.
Change-Id: I5c313324e1f213ab6453d82f41ae5e59de809a5b
without circular references we do not need weak goal pointers except for
caches, which should not prevent goal destructors running. caches though
cannot create circular references even when they keep strong references.
if we removed goals from caches when their work() is fully finished, not
when their destructors are run, we could keep strong pointers in caches.
since we do not gain much from this we keep those pointers weak for now.
Change-Id: I1d4a6850ff5e264443c90eb4531da89f5e97a3a0