}

	if m.status == scanStateStarted && update.status != scanStateStarted {
		m.status = update.status
	}

	if m.status == scanStateStarted && time.Since(m.lastHandout) > metacacheMaxClientWait {
		// Drop if client hasn't been seen for 3 minutes.
		m.status = scanStateError
		m.error = "client not seen"
	}

	if m.error == "" && update.error != "" {
		m.error = update.error
		m.status = scanStateError

}

type bufPool struct {
	sz   int
	pool sync.Pool
}

func (b *bufPool) Put(buf []byte) {
	if cap(buf) < b.sz || cap(buf) > b.sz*2 {
		// Buffer too small or will likely leak memory after being expanded.
		// Drop it.
		return
	}
	b.pool.Put(&buf)
}

func (b *bufPool) Get() []byte {
	bufp := b.pool.Get().(*[]byte)
	return (*bufp)[:b.sz]
}

func newBufPool(sz int) httputil.BufferPool {