Method Evict

src/leveldb/persistent_cache/persistent_cache_metadata.cc:31–57

}

CacheFile* PersistentCacheMetaData::Evict() {
  CacheFile* evicted_file = nullptr;

  {
    std::lock_guard<std::mutex> _(evictable_files_lock_);
    if (!evictable_files_.empty()) {
      auto iter = evictable_files_.begin();
      while (iter != evictable_files_.end() && (*iter)->refs_) {
        ++iter;
      }
      if (iter != evictable_files_.end()) {
        evicted_file = *iter;
        evictable_files_.erase(iter);
        LEVELDB_LOG("Find evictable file for evict, current evictable files size: %lu\n",
                    evictable_files_.size());
      }
    }
  }

  if (!evicted_file) {
    using std::placeholders::_1;
    auto fn = std::bind(&PersistentCacheMetaData::RemoveFileInfo, this, _1);
    evicted_file = cache_file_index_.Evict(fn);
  }

  return evicted_file;
}

void PersistentCacheMetaData::Clear() {
  cache_file_index_.Clear([](CacheFile* arg) { delete arg; });