[COUCHDB-1218] Better logger performance

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Won't Fix
• Assignee: Filipe David Borba Manana
• Reporter: Filipe David Borba Manana
• Created: 12/Jul/11 16:33
• Updated: 02/Sep/18 06:33
• Resolved: 02/Sep/18 06:33

Description

I made some experiments with OTP's disk_log module (available since 2001 at least) to use it to manage the log file.
It turns out I got better throughput by using it. Basically it adopts a strategy similar to the asynchronous couch_file Damien described in this thread:

http://mail-archives.apache.org/mod_mbox/couchdb-dev/201106.mbox/[e-mail]%3E

Here's a benchmark with relaximation, 50 writers, 100 readers, documents of 1Kb, delayed_commits set to false and 'info' log level (default):

http://graphs.mikeal.couchone.com/#/graph/9e19f6d9eeb318c70cabcf67bc013c7f

The reads got a better throughput (bottom graph, easier to visualize).

The patch (also attached here), which has a descriptive comment, is at:

https://github.com/fdmanana/couchdb/compare/logger_perf.patch

Issue Links

• relates to: COUCHDB-1380 logrotate doesn't work correctly with couchdb 1.2.x