updated vendor
This commit is contained in:
+1
-1
@@ -109,7 +109,7 @@ func (g *Group) TryGo(f func() error) bool {
|
||||
if g.sem != nil {
|
||||
select {
|
||||
case g.sem <- token{}:
|
||||
// Note: this allows barging iff channels in general allow barging.
|
||||
// Note: this allows barging if and only if channels in general allow barging.
|
||||
default:
|
||||
return false
|
||||
}
|
||||
|
||||
+5
-5
@@ -83,7 +83,7 @@ func (s *Weighted) Acquire(ctx context.Context, n int64) error {
|
||||
default:
|
||||
isFront := s.waiters.Front() == elem
|
||||
s.waiters.Remove(elem)
|
||||
// If we're at the front and there're extra tokens left, notify other waiters.
|
||||
// If we're at the front and there are extra tokens left, notify other waiters.
|
||||
if isFront && s.size > s.cur {
|
||||
s.notifyWaiters()
|
||||
}
|
||||
@@ -139,15 +139,15 @@ func (s *Weighted) notifyWaiters() {
|
||||
|
||||
w := next.Value.(waiter)
|
||||
if s.size-s.cur < w.n {
|
||||
// Not enough tokens for the next waiter. We could keep going (to try to
|
||||
// Not enough tokens for the next waiter. We could keep going (to try to
|
||||
// find a waiter with a smaller request), but under load that could cause
|
||||
// starvation for large requests; instead, we leave all remaining waiters
|
||||
// blocked.
|
||||
//
|
||||
// Consider a semaphore used as a read-write lock, with N tokens, N
|
||||
// readers, and one writer. Each reader can Acquire(1) to obtain a read
|
||||
// lock. The writer can Acquire(N) to obtain a write lock, excluding all
|
||||
// of the readers. If we allow the readers to jump ahead in the queue,
|
||||
// readers, and one writer. Each reader can Acquire(1) to obtain a read
|
||||
// lock. The writer can Acquire(N) to obtain a write lock, excluding all
|
||||
// of the readers. If we allow the readers to jump ahead in the queue,
|
||||
// the writer will starve — there is always one token available for every
|
||||
// reader.
|
||||
break
|
||||
|
||||
Reference in New Issue
Block a user