func (b *Batch[K, T]) GetByKey(key K) (T, bool) {
	b.Lock()
	defer b.Unlock()

	item, ok := b.items[key]
	return item, ok
}

// Len returns the no of items in the batch
func (b *Batch[K, T]) Len() int {
	b.Lock()
	defer b.Unlock()

	return len(b.keys)
}

// IsFull checks if the batch is full or not
func (b *Batch[K, T]) IsFull() bool {
	b.Lock()
	defer b.Unlock()

	return b.isFull()
}

func (p *podNetnsCache) Get(uid string) Netns {
	// lock current snapshot pod map
	p.mu.RLock()
	defer p.mu.RUnlock()
	if info, f := p.currentPodCache[uid]; f {
		return info.Netns
	}
	return nil
}

// make sure uid is in the cache, even if we don't have a netns
func (p *podNetnsCache) Ensure(uid string) {
	p.mu.Lock()
	defer p.mu.Unlock()
	if _, ok := p.currentPodCache[uid]; !ok {

 *
 * <ul>
 *   <li>for an unnested {@code lock()} and {@code unlock()}, a cycle detecting lock takes 38ns as
 *       opposed to the 24ns taken by a plain lock.
 *   <li>for nested locking, the cost increases with the depth of the nesting:
 *       <ul>
 *         <li>2 levels: average of 64ns per lock()/unlock()
 *         <li>3 levels: average of 77ns per lock()/unlock()
 *         <li>4 levels: average of 99ns per lock()/unlock()

	if responses == nil {
		return nil, errors.New("RequestStream: responses channel is nil")
	}
	m.init = true
	m.respMu.Lock()
	if m.closed {
		m.respMu.Unlock()
		return nil, ErrDisconnected
	}
	m.respWait = responses // Route directly to output.
	m.respMu.Unlock()

	// Try to grab an initial block.
	m.singleResp = false
	m.RecvSeq = m.SendSeq // Sync
	if cap(requests) > 0 {

	fw *flate.Writer
}

func (w *pooledFlateWriter) Write(p []byte) (n int, err error) {
	w.mu.Lock()
	defer w.mu.Unlock()
	if w.fw == nil {
		return 0, errors.New("Write after Close")
	}
	return w.fw.Write(p)
}

func (w *pooledFlateWriter) Close() error {
	w.mu.Lock()
	defer w.mu.Unlock()
	var err error
	if w.fw != nil {
		err = w.fw.Close()
		flateWriterPool.Put(w.fw)
		w.fw = nil
	}

	}
	ps.Lock()
	defer ps.Unlock()

	sub := &Sub[T]{ch: subCh, types: Mask(mask.Mask()), filter: filter}
	ps.subs = append(ps.subs, sub)

	// We hold a lock, so we are safe to update
	combined := Mask(atomic.LoadUint64(&ps.types))
	combined.Merge(Mask(mask.Mask()))
	atomic.StoreUint64(&ps.types, uint64(combined))

	go func() {
		<-doneCh

		ps.Lock()
		defer ps.Unlock()

type IAMStorageAPI interface {
	// The role of the read-write lock is to prevent go routines from
	// concurrently reading and writing the IAM storage. The (r)lock()
	// functions return the iamCache. The cache can be safely written to
	// only when returned by `lock()`.
	lock() *iamCache
	unlock()
	rlock() *iamCache
	runlock()
	getUsersSysType() UsersSysType

	}

	// if no update is needed return right away.
	if !update {
		z.poolMetaMutex.Lock()
		z.poolMeta = meta
		z.poolMetaMutex.Unlock()
	} else {
		newMeta := newPoolMeta(z, meta)
		if err = newMeta.save(ctx, z.serverPools); err != nil {
			return err
		}
		z.poolMetaMutex.Lock()
		z.poolMeta = newMeta
		z.poolMetaMutex.Unlock()
	}

	pools := meta.returnResumablePools()

		t.Fatal("Unexpected error", err)
	}
}

// Tests lock and unlock semantics.
func TestLockAndUnlock(t *testing.T) {
	f, err := os.CreateTemp("", "lock")
	if err != nil {
		t.Fatal(err)
	}
	f.Close()
	defer func() {
		err = os.Remove(f.Name())
		if err != nil {
			t.Fatal(err)
		}
	}()

	// lock the file
	l, err := LockedOpenFile(f.Name(), os.O_WRONLY, 0o600)
	if err != nil {

}

func (t *tierMetrics) logSuccess(tier string) {
	t.Lock()
	defer t.Unlock()

	stat := t.requestsCount[tier]
	stat.success++
	t.requestsCount[tier] = stat
}

func (t *tierMetrics) logFailure(tier string) {
	t.Lock()
	defer t.Unlock()

	stat := t.requestsCount[tier]
	stat.failure++
	t.requestsCount[tier] = stat
}

var (