Log the open-options to the LOG.

Summary: Log the open-options to the LOG. Use options_ instead of options because SanitizeOptions could modify the max_file_open limit.

Test Plan: num db_bench

Reviewers: heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D4833

db/db_impl.cc

@@ -141,12 +141,14 @@ DBImpl::DBImpl(const Options& options, const std::string& dbname)
 
   stats_ = new CompactionStats[options.num_levels];
   // Reserve ten files or so for other uses and give the rest to TableCache.
-  const int table_cache_size = options.max_open_files - 10;
+  const int table_cache_size = options_.max_open_files - 10;
   table_cache_ = new TableCache(dbname_, &options_, table_cache_size);
 
   versions_ = new VersionSet(dbname_, &options_, table_cache_,
                              &internal_comparator_);
 
+  options_.Dump(options_.info_log);
+
 #ifdef USE_SCRIBE
   logger_ = new ScribeLogger("localhost", 1456);
 #endif

include/leveldb/options.h

@@ -206,6 +206,8 @@ struct Options {
 
   // Create an Options object with default values for all fields.
   Options();
+
+  void Dump(Logger * log) const;
 };
 
 // Options that control read operations

util/options.cc

@@ -6,6 +6,7 @@
 
 #include "leveldb/comparator.h"
 #include "leveldb/env.h"
+#include "leveldb/filter_policy.h"
 
 namespace leveldb {
 
@@ -39,4 +40,25 @@ Options::Options()
       db_stats_log_interval(1800) {
 }
 
+void
+Options::Dump(
+    Logger * log) const
+{
+    Log(log,"            Options.comparator: %s", comparator->Name());
+    Log(log,"     Options.create_if_missing: %d", create_if_missing);
+    Log(log,"       Options.error_if_exists: %d", error_if_exists);
+    Log(log,"       Options.paranoid_checks: %d", paranoid_checks);
+    Log(log,"                   Options.env: %p", env);
+    Log(log,"              Options.info_log: %p", info_log);
+    Log(log,"     Options.write_buffer_size: %zd", write_buffer_size);
+    Log(log,"        Options.max_open_files: %d", max_open_files);
+    Log(log,"           Options.block_cache: %p", block_cache);
+    Log(log,"            Options.block_size: %zd", block_size);
+    Log(log,"Options.block_restart_interval: %d", block_restart_interval);
+    Log(log,"           Options.compression: %d", compression);
+    Log(log,"         Options.filter_policy: %s", filter_policy == NULL ? "NULL" : filter_policy->Name());
+
+}   // Options::Dump
+
+
 }  // namespace leveldb