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Code reviewHardcr-g410
Subject Concurrency bugsLevel Senior–Staff~30 minCommon in Concurrency interviewsIndustries Software development

Question

Review this Go bounded semaphore used to cap concurrent uploads. Workers call Acquire before an upload and Release after.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.

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Code to reviewgo
type Sem struct {	mu    sync.Mutex	cond  *sync.Cond	avail int} func NewSem(n int) *Sem {	s := &Sem{avail: n}	s.cond = sync.NewCond(&s.mu)	return s} func (s *Sem) Acquire() {	s.mu.Lock()	if s.avail == 0 {		s.cond.Wait()	}	s.avail--	s.mu.Unlock()} func (s *Sem) Release() {	s.mu.Lock()	s.avail++	s.cond.Signal()	s.mu.Unlock()}
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