content: package act.internal.util;
  
  /*-
   * #%L
   * ACT Framework
   * %%
   * Copyright (C) 2014 - 2018 ActFramework
   * %%
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   * 
   *      http://www.apache.org/licenses/LICENSE-2.0
   * 
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   * #L%
   */
  
  import act.Act;
  import act.conf.ActConfig;
  
  // Calculate the default strBuf retention limit size
  public class StrBufRetentionLimitCalculator {
      public int calculate() {
          long availableKilobytes = availableMemorySize() / 1024;
          long reservedForStrBuf = availableKilobytes / 128;
          long reservedForStrBufPerThread = reservedForStrBuf / threadsCount();
          return (int) reservedForStrBufPerThread;
      }
  
      private long availableMemorySize() {
          Runtime rt = Runtime.getRuntime();
          rt.gc();
          return rt.freeMemory();
      }
  
      private int threadsCount() {
          int workerThreads = Runtime.getRuntime().availableProcessors() * 2 * 8;
          ActConfig conf = Act.conf();
          int maxWorkerThreads = null == conf ? 0 : conf.xioMaxWorkerThreads();
          return maxWorkerThreads > 0 ? Math.min(maxWorkerThreads, workerThreads) : workerThreads;
      }
  
      public static void main(String[] args) {
          System.out.println(new StrBufRetentionLimitCalculator().calculate());
      }
  }
  