Monday, June 29, 2015
Examining performance for MongoDB and the insert benchmark
My previous post has results for the insert benchmark when the database fits in RAM. In this post I look at MongoDB performance as the database gets larger than RAM. I ran these tests while preparing for a talk and going on vacation, so I am vague on some of the configuration details. The summary is that RocksDB does much better than mmapv1 and the WiredTiger B-Tree when the database is larger than RAM because it is more IO efficient. RocksDB doesn't read index pages during non-unique secondary index maintenance. It also does fewer but larger writes rather than the many smaller/random writes required by a B-Tree. This is more of a benefit for servers that use disk.