@Override public Long call() { try { LlapManagementProtocolClientImpl client = new LlapManagementProtocolClientImpl(conf, instance.getHost(), instance.getManagementPort(), retryPolicy, socketFactory); LlapDaemonProtocolProtos.PurgeCacheResponseProto resp = client.purgeCache(null, LlapDaemonProtocolProtos .PurgeCacheRequestProto.newBuilder().build()); return resp.getPurgedMemoryBytes(); } catch (Exception e) { LOG.warn("Exception while purging cache.", e); return 0L; } } }