private long getTotalPostCompressedBytes() {
    GemFireCacheImpl cache = (GemFireCacheImpl) getCache();
    return cache.getCachePerfStats().getTotalPostCompressedBytes();
  }
Returns the the number of post-compressed bytes stat for the cache.
geode-core/src/distributedTest/java/org/apache/geode/internal/compression/CompressionStatsDUnitTest.java