October 2023 - ruby-core - ml.ruby-lang.org

[ruby-core:113788] [Ruby master Bug#19717] `ConditionVariable#signal` is not fair when the wakeup is consistently spurious.
by ioquatix (Samuel Williams) 10 Jan '24

10 Jan '24

Issue #19717 has been reported by ioquatix (Samuel Williams). ---------------------------------------- Bug #19717: `ConditionVariable#signal` is not fair when the wakeup is consistently spurious. https://bugs.ruby-lang.org/issues/19717 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- For background, see this issue <https://github.com/socketry/async/issues/99>. It looks like `ConditionVariable#signal` is not fair, if the calling thread immediately reacquires the resource. I've given a detailed reproduction here as it's non-trivial: <https://github.com/ioquatix/ruby-condition-variable-timeout>. Because the spurious wakeup occurs, the thread is pushed to the back of the waitq, which means any other waiting thread will acquire the resource, and that thread will perpetually be at the back of the queue. I believe the solution is to change `ConditionVarialbe#signal` should only remove the thread from the waitq if it's possible to acquire the lock. Otherwise it should be left in place, so that the order is retained, this should result in fair scheduling. -- https://bugs.ruby-lang.org/

3 12

[ruby-core:115104] [Ruby master Feature#19965] Make the name resolution interruptible
by mame (Yusuke Endoh) 09 Jan '24

09 Jan '24

Issue #19965 has been reported by mame (Yusuke Endoh). ---------------------------------------- Feature #19965: Make the name resolution interruptible https://bugs.ruby-lang.org/issues/19965 * Author: mame (Yusuke Endoh) * Status: Open * Priority: Normal ---------------------------------------- ## Problem Currently, Ruby name resolution is not interruptible. ``` $ cat /etc/resolv.conf nameserver 198.51.100.1 $ ./local/bin/ruby -rsocket -e 'Addrinfo.getaddrinfo("www.ruby-lang.org", 80)' ^C^C^C^C ``` If you set a non-responsive IP as the nameserver, you cannot stop `Addrinfo.getaddrinfo` by pressing Ctrl+C. Note that `Timeout.timeout` does not work either. This is because there is no way to cancel `getaddrinfo(3)`. ## Proposal I wrote a patch to make `getaddrinfo(3)` work in a separate pthread. https://github.com/ruby/ruby/pull/8695 Whenever it needs name resolution, it creates a worker pthread, and executes `getaddrinfo(3)` in it. The caller thread waits for the worker to complete. When an interrupt occurs, the caller thread leaves stop waiting and leaves the worker pthread. The detached worker pthread will exit after `getaddrinfo(3)` completes (or name resolution times out). ## Evaluation By applying this patch, name resolution is now interruptible. ``` $ ./local/bin/ruby -rsocket -e 'pp Addrinfo.getaddrinfo("www.ruby-lang.org", 80)' ^C-e:1:in `getaddrinfo': Interrupt from -e:1:in `<main>' ``` As a drawback, name resolution performance will be degraded. ``` 10000.times { Addrinfo.getaddrinfo("www.ruby-lang.org", 80) } # Before patch: 2.3 sec. # After ptach: 3.0 sec. ``` However, I think that name resolution is typically short enough for the application's runtime. For example, the difference is small for the performance of `URI.open`. ``` 100.times { URI.open("https://www.ruby-lang.org").read } # Before patch: 3.36 sec. # After ptach: 3.40 sec. ``` ## Alternative approaches I proposed using c-ares to resolve this issue (#19430). However, there was an opinion that it would be a problem that c-ares does not respect the platform-dependent own name resolution. ## Room for improvement * Currently, this patch works only when pthread is available. * It might be possible to force to stop the worker threads by using `pthread_cancel`. However, `pthread_cancel` with `getaddrinfo(3)` seems still premature; there seems to be a bug in glibc until recently: https://bugzilla.redhat.com/show_bug.cgi?id=1405071 https://sourceware.org/bugzilla/show_bug.cgi?id=20975 * It would be more efficient to pool worker pthreads instead of creating them each time. -- https://bugs.ruby-lang.org/

3 6

[ruby-core:112208] [Ruby master Bug#19409] Object's shape is reset after a ractor move
by luke-gru (Luke Gruber) 04 Jan '24

04 Jan '24

Issue #19409 has been reported by luke-gru (Luke Gruber). ---------------------------------------- Bug #19409: Object's shape is reset after a ractor move https://bugs.ruby-lang.org/issues/19409 * Author: luke-gru (Luke Gruber) * Status: Open * Priority: Normal * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- I believe an object should have the same shape after being moved from 1 ractor to another. ```ruby class Obj attr_accessor :a, :b, :c, :d def initialize @a = 1 @b = 2 @c = 3 end end r = Ractor.new do obj = receive #p RubyVM::Shape.of(obj) obj.d = 4 p obj.a, obj.b, obj.c, obj.d # gets wrong values due to object shape id being reset on object end obj = Obj.new #p RubyVM::Shape.of(obj) r.send(obj, move: true) r.take ``` -- https://bugs.ruby-lang.org/

2 2

[ruby-core:112211] [Ruby master Bug#19411] GC issue with moved objects
by luke-gru (Luke Gruber) 04 Jan '24

04 Jan '24

Issue #19411 has been reported by luke-gru (Luke Gruber). ---------------------------------------- Bug #19411: GC issue with moved objects https://bugs.ruby-lang.org/issues/19411 * Author: luke-gru (Luke Gruber) * Status: Open * Priority: Normal * ruby -v: 3.2.0 * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- This crashes: ```ruby class Obj def initialize @obj = 3 end end GC.stress = true r = Ractor.new do obj = receive p obj end obj = Obj.new r.send(obj, move: true) r.take ``` It only crashes with nested objects, if you remove the ivar set in `initialize` it works fine. Maybe missing `RB_GC_GUARD`? -- https://bugs.ruby-lang.org/

1 2

[ruby-core:112010] [Ruby master Bug#19375] File objects are currently shareable
by luke-gru (Luke Gruber) 29 Dec '23

29 Dec '23

Issue #19375 has been reported by luke-gru (Luke Gruber). ---------------------------------------- Bug #19375: File objects are currently shareable https://bugs.ruby-lang.org/issues/19375 * Author: luke-gru (Luke Gruber) * Status: Open * Priority: Normal * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- I don't know the internals of file.c but I don't think files are thread-safe. -- https://bugs.ruby-lang.org/

1 2

[ruby-core:111789] [Ruby master Feature#19333] Setting (Fiber Local|Thread Local|Fiber Storage) to nil should delete value in order to avoid memory leaks.
by ioquatix (Samuel Williams) 28 Dec '23

28 Dec '23

Issue #19333 has been reported by ioquatix (Samuel Williams). ---------------------------------------- Feature #19333: Setting (Fiber Local|Thread Local|Fiber Storage) to nil should delete value in order to avoid memory leaks. https://bugs.ruby-lang.org/issues/19333 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal ---------------------------------------- As it stands, Fiber Locals, Thread Locals and Fiber Storage have no way of deleting key-value associations. ```ruby 100.times do |i| name = :"variable-#{i}" Thread.current[name] = 10 end ``` Because of this, dynamically generated associations can leak over time. This is worse for things like Threads that might be pooled (or maybe an argument against user-space pooling). In any case, having a way to delete those associations would allow application code to at least delete the associations when they no longer make sense. I propose that assigning `nil` to "locals" or "storage" should effectively delete them. e.g. ```ruby 100.times do |i| name = :"variable-#{i}" Thread.current[name] = 10 Thread.current[name] = nil # delete association end ``` A more invasive alternative would be to define new interfaces like `Thread::Local`, `Fiber::Local` and `Fiber::Storage::Local` (or something) which correctly clean up on GC. -- https://bugs.ruby-lang.org/

3 8

[ruby-core:112446] [Ruby master Bug#19442] Remove USE_RINCGC flag
by eightbitraptor (Matthew Valentine-House) 28 Dec '23

28 Dec '23

Issue #19442 has been reported by eightbitraptor (Matthew Valentine-House). ---------------------------------------- Bug #19442: Remove USE_RINCGC flag https://bugs.ruby-lang.org/issues/19442 * Author: eightbitraptor (Matthew Valentine-House) * Status: Open * Priority: Normal * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- [GitHub PR #7317](https://github.com/ruby/ruby/pull/7313) Ruby doesn't compile when USE_RINCGC is disabled. It's also not being tested in CI. As @nobu has pointed out in comments on the PR, fixing it is simple. I think there are 2 approaches we could take: 1. Remove `USE_RINCGC` entirely and always run with incremental GC enabled. We have a precedent for this: `USE_RGENGC=0` was removed [in this commit](https://github.com/ruby/ruby/commit/62c2b8c74e47652fc5bbaf6150f4acd… almost 3 years ago. `USE_RINCGC=0` is in a similar state. It has been broken for almost a year (since [this commit](https://github.com/ruby/ruby/commit/dde164e968e382d50b07ad455946888…) and [disabled in CI for more than 2 years](https://github.com/ruby/ruby/commit/46d3ea2c2569e2e5a9ee3e7e206f07f0…. 2. We could fix `USE_RINCGC`. If we do this we should re-enable the CI task so that we continue to keep it working in the future. I am very much in favour of option 1, because I don't think this flag is being actively used, and removing it will simplify the code and reduce the cognitive overhead of working with the GC. However I am happy to defer to the team here. -- https://bugs.ruby-lang.org/

6 9

[ruby-core:115208] [Ruby master Feature#19982] Bump required Visual Studio version to 2015 after 3.3
by kddnewton (Kevin Newton) 27 Dec '23

27 Dec '23

Issue #19982 has been reported by kddnewton (Kevin Newton). ---------------------------------------- Feature #19982: Bump required Visual Studio version to 2015 after 3.3 https://bugs.ruby-lang.org/issues/19982 * Author: kddnewton (Kevin Newton) * Status: Open * Priority: Normal ---------------------------------------- Visual Studio 2013 is finally being EOL'd next April. (https://learn.microsoft.com/en-us/visualstudio/productinfo/vs-servicing#old…) Let's drop support for it after Ruby 3.3 is released. If we bump the required version to Visual Studio 2015, we'll get better C99 support and be able to rely on some more standards. Personally I'm excited about `snprintf` being actually implemented. (https://learn.microsoft.com/en-us/cpp/overview/visual-cpp-language-conforma…) As support for the argument, CPython requires VS2017 (https://github.com/python/cpython/blob/main/PCbuild/readme.txt) and gnulib requires VS2015(https://www.gnu.org/software/gnulib/manual/html_node/Supported-Platf…. -- https://bugs.ruby-lang.org/

5 5

[ruby-core:113951] [Ruby master Bug#19738] `ObjectSpace.each_object.to_a` crashes in `make runirb`.
by ioquatix (Samuel Williams) 26 Dec '23

26 Dec '23

Issue #19738 has been reported by ioquatix (Samuel Williams). ---------------------------------------- Bug #19738: `ObjectSpace.each_object.to_a` crashes in `make runirb`. https://bugs.ruby-lang.org/issues/19738 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- ``` > make runirb RUBY_ON_BUG='gdb -x ./.gdbinit -p' ./miniruby -I./lib -I. -I.ext/common ./tool/runruby.rb --extout=.ext -- --disable-gems -r irb -e 'IRB.start("make runirb")' irb(main):001:0> ObjectSpace.each_object.to_a Assertion Failed: ./vm_method.c:1366:callable_method_entry_or_negative:RB_TYPE_P(klass, T_CLASS) || RB_TYPE_P(klass, T_ICLASS) ruby 3.3.0dev (2023-06-19T19:19:45Z master 9ff4399dec) [arm64-darwin22] ``` I have no idea why. ---Files-------------------------------- error.txt (12.9 KB) -- https://bugs.ruby-lang.org/

2 3

[ruby-core:114345] [Ruby master Bug#19831] warning message of linker with macOS Sonoma beta
by hsbt (Hiroshi SHIBATA) 26 Dec '23

26 Dec '23

Issue #19831 has been reported by hsbt (Hiroshi SHIBATA). ---------------------------------------- Bug #19831: warning message of linker with macOS Sonoma beta https://bugs.ruby-lang.org/issues/19831 * Author: hsbt (Hiroshi SHIBATA) * Status: Open * Priority: Normal * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- Xcode 15 beta and macOS Sonoma beta show the following warnings with `make` ``` (snip) linking miniruby ld: warning: ignoring duplicate library '-lpthread' miniruby: replacing existing signature exe/ruby: replacing existing signature builtin_binary.inc updated compiling builtin.c linking static-library libruby.3.3-static.a linking ruby ld: warning: ignoring duplicate library '-lgmp' ld: warning: ignoring duplicate library '-ldl' ld: warning: ignoring duplicate library '-lobjc' ld: warning: ignoring duplicate library '-lpthread' ld: warning: ignoring duplicate library '-lpthread' (snip) ``` I'm not investigate that yet. It may be caused by `ld-prime` that is new linker of macOS platform. ``` $ pkgutil --pkg-info=com.apple.pkg.CLTools_Executables package-id: com.apple.pkg.CLTools_Executables version: 15.0.0.0.1.1690355577 volume: / location: / install-time: 1690967267 ``` -- https://bugs.ruby-lang.org/

1 3