Drop custom implementation of Fiber::ExecutionContext::Concurrent#16135
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straight-shoota merged 3 commits intocrystal-lang:masterfrom Sep 11, 2025
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Gotta love those removed / added line ratios 😍
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NOTE: since the class overrides |
ysbaddaden
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feature/concurrent-context-extends-parallel-context
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The concurrent context doesn't exhibit any performance improvement over the parallel context (see #16135). So we may as well use a parallel context as default context, and allow resizing it for more parallelism (see #15956). The default configuration is without parallelism (MT:1), thus the execution context remains concurrent only, which is backward compatible (nothing changes). Resizing the context to enable parallelism will be at the discretion of the application: it can keep using the `CRYSTAL_WORKERS` environment variable, and/or fallback to the number of CPUs or use a hardcoded value, and/or provide a command line argument, or anything else. Co-authored-by: Johannes Müller <straightshoota@gmail.com>
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Co-authored-by: Johannes Müller <straightshoota@gmail.com>
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The
Concurrentimplementation mostly duplicates theParallelone, and the parallel schedulers now take a few shortcuts when parallelism is set to 1 (skip stealing, quick evloop check) andConcurrentdoesn't exhibit any noticeable performance improvement overParallel.Having a single implementation instead of two, almost identical, will ease maintenance.
I kept the type and didn't deprecate it yet. It's only value is that you can't mistakenly resize the context and an exception is raised when you try to (related to #15956).