Add the secondary cache information into LRUCache:: GetPrintableOptions (#10346)

Summary:
If the primary cache is LRU cache and there is a secondary cache, add  Secondary Cache printable options into LRUCache::GetPrintableOptions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10346

Test Plan:
1. Current Unit Tests should pass.
2. Use db_bench (with compressed_secondary_cache ) and the LOG should includes the new printable options from Seoncdary Cache.

Reviewed By: jay-zhuang

Differential Revision: D37779310

Pulled By: gitbw95

fbshipit-source-id: 88ce1f7df6b5f25740e598d9e7fa91e4c414cb8f

cache/compressed_secondary_cache.cc

@@ -139,7 +139,7 @@ std::string CompressedSecondaryCache::GetPrintableOptions() const {
   snprintf(buffer, kBufferSize, "    compression_type : %s\n",
            CompressionTypeToString(cache_options_.compression_type).c_str());
   ret.append(buffer);
-  snprintf(buffer, kBufferSize, "    compression_type : %d\n",
+  snprintf(buffer, kBufferSize, "    compress_format_version : %d\n",
            cache_options_.compress_format_version);
   ret.append(buffer);
   return ret;

cache/lru_cache.cc

@@ -757,6 +757,17 @@ void LRUCache::WaitAll(std::vector<Handle*>& handles) {
   }
 }
 
+std::string LRUCache::GetPrintableOptions() const {
+  std::string ret;
+  ret.reserve(20000);
+  ret.append(ShardedCache::GetPrintableOptions());
+  if (secondary_cache_) {
+    ret.append("  secondary_cache:\n");
+    ret.append(secondary_cache_->GetPrintableOptions());
+  }
+  return ret;
+}
+
 }  // namespace lru_cache
 
 std::shared_ptr<Cache> NewLRUCache(

cache/lru_cache.h

@@ -482,6 +482,7 @@ class LRUCache
   virtual DeleterFn GetDeleter(Handle* handle) const override;
   virtual void DisownData() override;
   virtual void WaitAll(std::vector<Handle*>& handles) override;
+  std::string GetPrintableOptions() const override;
 
   //  Retrieves number of elements in LRU, for unit test purpose only.
   size_t TEST_GetLRUSize();