EXPECT_TRUE(cache.Lookup("b", &value));
  EXPECT_EQ(value, 2);
  EXPECT_TRUE(cache.Lookup("c", &value));
  EXPECT_EQ(value, 3);
  EXPECT_TRUE(cache.Lookup("d", &value));
  EXPECT_EQ(value, 4);
  cache.Clear();
  EXPECT_FALSE(cache.Lookup("a", &value));
  EXPECT_FALSE(cache.Lookup("b", &value));
  EXPECT_FALSE(cache.Lookup("c", &value));
  EXPECT_FALSE(cache.Lookup("d", &value));
}

  new_entry->timestamp = timer_seconds_();
  block_map_.emplace(std::make_pair(key, new_entry));
  return new_entry;
}

// Remove blocks from the cache until we do not exceed our maximum size.
void RamFileBlockCache::Trim() {
  while (!lru_list_.empty() && cache_size_ > max_bytes_) {
    RemoveBlock(block_map_.find(lru_list_.back()));
  }
}

/// Move the block to the front of the LRU list if it isn't already there.

  calls.push_back(block_size);
  // Cache miss followed by cache hit.
  TF_EXPECT_OK(ReadCache(&cache, "", block_size, 1, &out));
  TF_EXPECT_OK(ReadCache(&cache, "", block_size, 1, &out));
  calls.push_back(2 * block_size);
  // Cache miss followed by cache hit.  Causes eviction of LRU element.
  TF_EXPECT_OK(ReadCache(&cache, "", 2 * block_size, 1, &out));

// function. Otherwise return nullptr in result and error Status from the
// function.
//
// If `library_filename` has already been loaded, we return a cached handle.
// Device and Kernels/Ops are registered as globals when a library is loaded
// for the first time.
TF_Library* TF_LoadPluggableDeviceLibrary(const char* library_filename,

  TFE_ContextAddFunctionDef(ctx, function_def.data(), function_def.size(),
                            status);
  CHECK_EQ(TF_OK, TF_GetCode(status)) << TF_Message(status);

  for (bool clear_cache : {true, false, true}) {
    if (clear_cache) {
      TFE_ContextClearCaches(ctx);
    }
    TFE_TensorHandle* m = TestMatrixTensorHandle(ctx);
    TFE_TensorHandle* retval[1] = {nullptr};
    int num_retvals = 1;

  // Since `p` is allocated by plugin, free it using plugin's method.
  plugin_memory_free_(p);
  return ret;
}

void ModularFileSystem::FlushCaches(TransactionToken* token) {
  if (ops_->flush_caches != nullptr) ops_->flush_caches(filesystem_.get());
}

Status ModularFileSystem::SetOption(const std::string& name,
                                    const std::vector<string>& values) {

      });

  uint64_t stat_cache_max_age = kStatCacheDefaultMaxAge;
  size_t stat_cache_max_entries = kStatCacheDefaultMaxEntries;
  const char* stat_cache_max_age_env = std::getenv(kStatCacheMaxAge);
  if (stat_cache_max_age_env &&
      absl::SimpleAtoi(stat_cache_max_age_env, &value)) {
    stat_cache_max_age = value;
  }
  const char* stat_cache_max_entries_env = std::getenv(kStatCacheMaxEntries);

}

Status ImmediateExecutionTensorHandle::SummarizeValue(
    std::string& summary) const {
  Status status;
  AbstractTensorPtr resolved(
      // TODO(allenl): Resolve should be const, and the caches that get updated
      // marked mutable.
      const_cast<ImmediateExecutionTensorHandle*>(this)->Resolve(&status));
  if (!status.ok()) {
    return status;
  }
  summary = resolved->SummarizeValue();