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43 lines
1.4 KiB
Markdown
43 lines
1.4 KiB
Markdown
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## pwalk: parallel implementation of filepath.Walk
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This is a wrapper for [filepath.Walk](https://pkg.go.dev/path/filepath?tab=doc#Walk)
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which may speed it up by calling multiple callback functions (WalkFunc) in parallel,
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utilizing goroutines.
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By default, it utilizes 2\*runtime.NumCPU() goroutines for callbacks.
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This can be changed by using WalkN function which has the additional
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parameter, specifying the number of goroutines (concurrency).
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### Caveats
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Please note the following limitations of this code:
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* Unlike filepath.Walk, the order of calls is non-deterministic;
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* Only primitive error handling is supported:
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* filepath.SkipDir is not supported;
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* no errors are ever passed to WalkFunc;
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* once any error is returned from any WalkFunc instance, no more new calls
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to WalkFunc are made, and the error is returned to the caller of Walk;
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* if more than one walkFunc instance will return an error, only one
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of such errors will be propagated and returned by Walk, others
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will be silently discarded.
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### Documentation
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For the official documentation, see
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https://pkg.go.dev/github.com/opencontainers/selinux/pkg/pwalk?tab=doc
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### Benchmarks
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For a WalkFunc that consists solely of the return statement, this
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implementation is about 10% slower than the standard library's
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filepath.Walk.
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Otherwise (if a WalkFunc is doing something) this is usually faster,
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except when the WalkN(..., 1) is used.
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