45 lines
1 KiB
Go
45 lines
1 KiB
Go
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package vsphere
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import (
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"context"
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"sync"
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)
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// throttledExecutor provides a simple mechanism for running jobs in separate
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// goroutines while limit the number of concurrent jobs running at any given time.
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type throttledExecutor struct {
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limiter chan struct{}
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wg sync.WaitGroup
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}
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// newThrottledExecutor creates a new ThrottlesExecutor with a specified maximum
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// number of concurrent jobs
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func newThrottledExecutor(limit int) *throttledExecutor {
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if limit == 0 {
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panic("Limit must be > 0")
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}
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return &throttledExecutor{limiter: make(chan struct{}, limit)}
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}
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// run schedules a job for execution as soon as possible while respecting the maximum concurrency limit.
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func (t *throttledExecutor) run(ctx context.Context, job func()) {
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t.wg.Add(1)
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go func() {
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defer t.wg.Done()
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select {
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case t.limiter <- struct{}{}:
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defer func() {
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<-t.limiter
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}()
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job()
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case <-ctx.Done():
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return
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}
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}()
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}
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// wait blocks until all scheduled jobs have finished
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func (t *throttledExecutor) wait() {
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t.wg.Wait()
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}
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