@Override
    public void deleteAll(Collection<K> keys) {
        long startNanos = Timer.nanos();
        try {
            delegate.deleteAll(keys);
        } finally {
            deleteAllProbe.recordValue(Timer.nanosElapsed(startNanos));
        }
    }
@Test
    public void deleteAll() {
        List<String> keys = Arrays.asList("1", "2");

        cacheStore.deleteAll(keys);

        verify(delegate).deleteAll(keys);
        assertProbeCalledOnce("deleteAll");
    }