Move three info logging within DB Mutex to use log buffer (#10029)

Summary:
info logging with DB Mutex could potentially invoke I/O and cause performance issues. Move three of the cases to use log buffer.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10029

Test Plan: Run existing tests.

Reviewed By: jay-zhuang

Differential Revision: D36561694

fbshipit-source-id: cabb93fea299001a6b4c2802fcba3fde27fa062c

db/compaction/compaction_job.cc

@@ -2115,10 +2115,10 @@ Status CompactionJob::InstallCompactionResults(
 
   {
     Compaction::InputLevelSummaryBuffer inputs_summary;
-    ROCKS_LOG_INFO(db_options_.info_log,
+    ROCKS_LOG_BUFFER(log_buffer_,
                      "[%s] [JOB %d] Compacted %s => %" PRIu64 " bytes",
-                   compaction->column_family_data()->GetName().c_str(), job_id_,
-                   compaction->InputLevelSummary(&inputs_summary),
+                     compaction->column_family_data()->GetName().c_str(),
+                     job_id_, compaction->InputLevelSummary(&inputs_summary),
                      compact_->total_bytes + compact_->total_blob_bytes);
   }
 

db/db_impl/db_impl_compaction_flush.cc

@@ -1857,11 +1857,12 @@ Status DBImpl::RunManualCompaction(
     }
   }
 
-  ROCKS_LOG_INFO(immutable_db_options_.info_log,
-                 "[%s] Manual compaction starting", cfd->GetName().c_str());
-
   LogBuffer log_buffer(InfoLogLevel::INFO_LEVEL,
                        immutable_db_options_.info_log.get());
+
+  ROCKS_LOG_BUFFER(&log_buffer, "[%s] Manual compaction starting",
+                   cfd->GetName().c_str());
+
   // We don't check bg_error_ here, because if we get the error in compaction,
   // the compaction will set manual.status to bg_error_ and set manual.done to
   // true.

db/flush_job.cc

@@ -951,7 +951,7 @@ Status FlushJob::WriteLevel0Table() {
       }
       LogFlush(db_options_.info_log);
     }
-    ROCKS_LOG_INFO(db_options_.info_log,
+    ROCKS_LOG_BUFFER(log_buffer_,
                      "[%s] [JOB %d] Level-0 flush table #%" PRIu64 ": %" PRIu64
                      " bytes %s"
                      "%s",