Bug #90739 MySQL Router doesn't support 500 connections
Submitted: 3 May 2018 17:53 Modified: 4 May 2018 0:58
Reporter: Alexandre Almeida Email Updates:
Status: Duplicate Impact on me:
None 
Category:MySQL Router Severity:S1 (Critical)
Version:2.1.5 OS:CentOS (7X)
Assigned to: CPU Architecture:x86
Tags: Connections, MySQL, mysqlrouter, router, router

[3 May 2018 17:53] Alexandre Almeida 
Description:
With more than 500 MySQL Router abends. Actually, 511 connections. On a small enviroment with 2 servers with Centos 7X, MySQL 5.7, MySQL Router 2.1.5 and Keepalived, designed to support a website with the CMS wordpress.

Everything goes like a charm below 500 simultaneous connections. However, when 511 connections hit the MySQL Router, it does stop accepting connections. The binary still running, but, no connection is accept anymore.

How to repeat:
Use mysqlslap to connect to MySQL Router with more than 600 simultaneous connections.
[4 May 2018 0:58] MySQL Verification Team 
Thank you for the bug report. Duplicate of bug: https://bugs.mysql.com/bug.php?id=80260. Please see last comment about the ~500 known limitation:

 [5 Jan 3:12] Philip Olson

Posted by developer:
 
This change is now documented in several places, including: the release notes, the FAQ, and Router's max_connections documentation that previously referenced this known ~500 connection limitation.

This is documented as a v8.0.4 change that is tracked via WL #9857.