Thread safety improvements

[jpsamaroo]

Rebase of JuliaLang/julia#42239 plus fixes a thread safety issue in init_multi.

Intended to fix/improve #73

[jpsamaroo]

Depends on JuliaLang/julia#5 for CI

[codecov]

Codecov Report

Merging #4 (88680df) into master (8799660) will increase coverage by 0.15%.
The diff coverage is 97.05%.

@@            Coverage Diff             @@
##           master       JuliaLang/julia#4      +/-   ##
==========================================
+ Coverage   79.19%   79.34%   +0.15%     
==========================================
  Files          10       10              
  Lines        1951     1966      +15     
==========================================
+ Hits         1545     1560      +15     
  Misses        406      406              

Files	Coverage Δ
src/cluster.jl	74.15% <100.00%> (+0.67%)	⬆️
src/managers.jl	46.53% <0.00%> (ø)

[JamesWrigley]

I've tried a rebased version of this branch on latest master, can confirm the example test from #73 passes 👍

➜  Distributed.jl git:(jps/threadsafe_workerstate) ~/git/julia/julia                              
               _
   _       _ _(_)_     |  Documentation: https://docs.julialang.org
  (_)     | (_) (_)    |
   _ _   _| |_  __ _   |  Type "?" for help, "]?" for Pkg help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 1.12.0-DEV.321 (2024-04-09)
 _/ |\__'_|_|_|\__'_|  |  Commit 7099bddd5f* (0 days old master)
|__/                   |

(@v1.12) pkg> st
Status `~/.julia/environments/v1.12/Project.toml`
  [295af30f] Revise v3.5.14

julia> include("distributed-thread-safety.jl")
Test Summary:               | Pass  Total     Time
RemoteChannel is threadsafe |   64     64  1m53.2s
Test.DefaultTestSet("RemoteChannel is threadsafe", Any[Test.DefaultTestSet("from worker 1 to 1 via 1", Any[Test.DefaultTestSet("from thread 1.1 to 1.1", Any[], 4, false, false, true, 1.712685455788765e9, 1.712685465251433e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from thread 1.2 to 1.1", Any[], 4, false, false, true, 1.71268546525156e9, 1.712685470893932e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from thread 1.1 to 1.2", Any[], 4, false, false, true, 1.712685470894084e9, 1.712685476819892e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from thread 1.2 to 1.2"
, Any[], 4, false, false, true, 1.712685476820029e9, 1.71268548236758e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl")], 0, false, false, true, 1.712685455788721e9, 1.712685482371097e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from worker 2 to 1 via 1", Any[Test.DefaultTestSet("from thread 2.1 to 1.1", Any[], 4, false, false, true, 1.712685482371207e9, 1.712685489590523e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from thread 2.2 to 1.1", Any[], 4, false, false, true, 1.712685489590582e9, 1.712685496875588e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from thread 2.1 to 1.2", Any[], 4, false, false, true, 1.712685496875651e9, 1.712685504261359e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from thread 2.2 to 1.2", Any[], 4, 
false, false, true, 1.712685504261427e9, 1.712685511562309e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl")], 0, false, false, true, 1.712685482371161e9, 1.712685511562352e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from worker 1 to 2 via 1", Any[Test.DefaultTestSet("from thread 1.1 to 2.1", Any[], 4, false, false, true, 1.712685511562474e9, 1.712685518686331e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from thread 1.2 to 2.1", Any[], 4, false, false, true, 1.712685518686465e9, 1.712685525761654e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from thread 1.1 to 2.2", Any[], 4, false, false, true, 1.712685525761734e9, 1.712685532856677e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from thread 1.2 to 2.2", Any[], 4, false, false, true, 1.712685532856761e9, 1.712685539948613e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl")], 0, false, false, true, 1.712685511562421e9, 1.712685539948652e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from worker 2 to 2 via 1", Any[Test.DefaultTestSet("from thread 2.1 to 2.1", Any[], 4, false, false, true, 1.712685539948781e9, 1.712685547250845e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from thread 2.2 to 2.1", Any[], 4, false, false, true, 1.712685547250929e9, 1.712685554467226e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from th
read 2.1 to 2.2", Any[], 4, false, false, true, 1.712685554467299e9, 1.712685561768197e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl"), Test.DefaultTestSet("from thread 2.2 to 2.2", Any[], 4, false, false, true, 1.71268556176827e9, 1.712685568972127e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl")], 0, false, false, true, 1.712685539948732e9, 1.712685568972152e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl")], 0, false, false, true, 1.71268545575782e9, 1.712685568972163e9, false, "/home/james/git/Distributed.jl/distributed-thread-safety.jl")

I'll also try running the Julia tests with that version.

[JamesWrigley]

I had some issues with my machine running out of memory so I skipped the SparseArrays and LinearAlgebra tests with tests/runtests.jl -LinearAlgebra -SparseArrays. I saw failures with Artifacts:

Error in testset Artifacts:
Test Failed at /home/james/git/julia/usr/share/julia/stdlib/v1.12/Artifacts/test/runtests.jl:57
  Expression: load_overrides() == empty_output
   Evaluated: Dict{Symbol, Any}(:UUID => Dict{Base.UUID, Dict{String, Union{Base.SHA1, String}}}(Base.UUID("6b5019fb-a83d-5b4e-a9f7-678a36c28df7") => Dict("jlqml" => "/home/james/git/jlqml/build")), :hash => Dict{Base.SHA1, Union{Base.SHA1
, String}}()) == Dict{Symbol, Any}(:UUID => Dict{Base.UUID, Dict{String, Union{Base.SHA1, String}}}(), :hash => Dict{Base.SHA1, Union{Base.SHA1, String}}())

Error in testset Artifacts:
Test Failed at /home/james/git/julia/usr/share/julia/stdlib/v1.12/Artifacts/test/runtests.jl:73
  Expression: load_overrides() == empty_output
   Evaluated: Dict{Symbol, Any}(:UUID => Dict{Base.UUID, Dict{String, Union{Base.SHA1, String}}}(Base.UUID("6b5019fb-a83d-5b4e-a9f7-678a36c28df7") => Dict("jlqml" => "/home/james/git/jlqml/build")), :hash => Dict{Base.SHA1, Union{Base.SHA1
, String}}()) == Dict{Symbol, Any}(:UUID => Dict{Base.UUID, Dict{String, Union{Base.SHA1, String}}}(), :hash => Dict{Base.SHA1, Union{Base.SHA1, String}}())

Error in testset Artifacts:
Test Failed at /home/james/git/julia/usr/share/julia/stdlib/v1.12/Artifacts/test/runtests.jl:87
  Expression: load_overrides(force = true) == empty_output
   Evaluated: Dict{Symbol, Any}(:UUID => Dict{Base.UUID, Dict{String, Union{Base.SHA1, String}}}(Base.UUID("6b5019fb-a83d-5b4e-a9f7-678a36c28df7") => Dict("jlqml" => "/home/james/git/jlqml/build")), :hash => Dict{Base.SHA1, Union{Base.SHA1
, String}}()) == Dict{Symbol, Any}(:UUID => Dict{Base.UUID, Dict{String, Union{Base.SHA1, String}}}(), :hash => Dict{Base.SHA1, Union{Base.SHA1, String}}())

Sockets (but I think this is something to do with my machine):

Error in testset Sockets:
Error During Test at /home/james/git/julia/usr/share/julia/stdlib/v1.12/Sockets/test/runtests.jl:228
  Test threw exception
  Expression: getnameinfo(ip"::ffff:0.1.1.1") == "::ffff:0.1.1.1"
  DNSError: ip"::ffff:1:101", temporary failure (EAI_AGAIN) 
  Stacktrace:
   [1] getnameinfo(address::Sockets.IPv6)
     @ Sockets ~/git/julia/usr/share/julia/stdlib/v1.12/Sockets/src/addrinfo.jl:246
   [2] top-level scope
     @ ~/git/julia/usr/share/julia/stdlib/v1.12/Sockets/test/runtests.jl:199
   [3] macro expansion
     @ ~/git/julia/usr/share/julia/stdlib/v1.12/Test/src/Test.jl:164 [inlined]
   [4] macro expansion
     @ ~/git/julia/usr/share/julia/stdlib/v1.12/Sockets/test/runtests.jl:228 [inlined]
   [5] macro expansion
     @ ~/git/julia/usr/share/julia/stdlib/v1.12/Test/src/Test.jl:164 [inlined]

And some errors from FileWatching:

      From worker 10:   error in running finalizer: ErrorException("`ccall` requires the compiler")                                                                                                                                            
      From worker 10:   iolock_begin at libuv.jl:48                                                                                                                                                                                            
      From worker 10:   uvfinalize at /home/james/git/julia/usr/share/julia/stdlib/v1.12/FileWatching/src/FileWatching.jl:331                                                                                                                  

But as far as I can tell these are unrelated to Distributed. If that's the case, would it be possible to get this merged and make a new release?

[JamesWrigley]

Is this why addprocs() always takes at least 1s for me? 🤔

[JamesWrigley]

Bump 🙈 Is there any chance of getting this merged in time for 1.11? CC @vchuravy

[JamesWrigley]

Superseded by #101.