From 829363b449fc6f0f9c973f530222f5767c625704 Mon Sep 17 00:00:00 2001
From: sdong <siying.d@fb.com>
Date: Mon, 2 Feb 2015 11:09:21 -0800
Subject: [PATCH] Options::PrepareForBulkLoad() to increase parallelism of
 flushes

Summary: Increasing parallelism of flushes will help bulk load throughput.

Test Plan: Compile it.

Reviewers: MarkCallaghan, yhchiang, rven, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D32685
---
 util/options.cc | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/util/options.cc b/util/options.cc
index 75307f13f..69aca5ab1 100644
--- a/util/options.cc
+++ b/util/options.cc
@@ -505,6 +505,15 @@ Options::PrepareForBulkLoad()
   // increasing the total time needed for compactions.
   num_levels = 2;
 
+  // Need to allow more write buffers to allow more parallism
+  // of flushes.
+  max_write_buffer_number = 6;
+  min_write_buffer_number_to_merge = 1;
+
+  // When compaction is disabled, more parallel flush threads can
+  // help with write throughput.
+  max_background_flushes = 4;
+
   // Prevent a memtable flush to automatically promote files
   // to L1. This is helpful so that all files that are
   // input to the manual compaction are all at L0.