Fix runaway thread explosion when ForkJoinPool parallelism is < 2 #43
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Last commit published: 3ec10cc0465f9f52e827986bc5a95fa29e667fe5 - version: PR PublishingThe artifacts published by this PR:
Repository DeclarationIn order to use the artifacts published by the PR, add the following repository to your buildscript: repositories {
maven {
name = "Maven for PR #43" // https://github.com/neoforged/InstallerTools/pull/43
url = uri("https://prmaven.neoforged.net/InstallerTools/pr43")
content {
includeModule("net.neoforged.installertools", "binarypatch-applier")
includeModule("net.neoforged.installertools", "binarypatcher")
includeModule("net.neoforged.installertools", "cli-utils")
includeModule("net.neoforged.installertools", "installertools")
includeModule("net.neoforged.installertools", "jarsplitter")
includeModule("net.neoforged.installertools", "problems-api")
includeModule("net.neoforged.installertools", "zipinject")
}
}
} |
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Technici4n
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Jan 8, 2026
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Looks good but why mention Java < 25? Did this behavior change?
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yes it did in 25 |
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🚀 This PR has been released as InstallerTools version |
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covers has observed in the wild that the installer may create a runaway number of threads (thousands upon thousands).
The analysis has shown that this is the case in java < 25 if the common ForkJoinPool has parallelism of less than 2. In that case, CompletableFuture#runAsync using that pool will fall back to use one thread per submitted task.
Since we submit tasks for every class in the game at once, that will lead to this issue.
The solution is to detect this and use a dedicated worker thread instead, which is also what Java 25 does.
See: https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/CompletableFuture.html