public static void evict(Configuration conf, Request request) {
    if (!HiveConf.getBoolVar(conf, HiveConf.ConfVars.LLAP_IO_PROACTIVE_EVICTION_ENABLED)) {
      return;
    }

    try {
      LlapRegistryService llapRegistryService = LlapRegistryService.getClient(conf);
      Collection<LlapServiceInstance> instances = llapRegistryService.getInstances().getAll();
      if (instances.size() == 0) {
        // Not in LLAP mode.
        return;
      }
      LOG.info("Requesting proactive LLAP cache eviction.");
      LOG.debug("Request: {}", request);
      // Fire and forget - requests are enqueued on the single threaded executor and this (caller) thread won't wait.
      for (LlapServiceInstance instance : instances) {
        EvictionRequestTask task = new EvictionRequestTask(conf, instance, request);
        EXECUTOR.execute(task);
      }

    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }
Trigger LLAP cache eviction of buffers related to entities residing in request parameter.
@param conf
@param request
ql/src/java/org/apache/hadoop/hive/llap/ProactiveEviction.java