Bug #101826 mysql router 8.0.22 write error: Resource temporarily unavailable
Submitted: 1 Dec 2020 21:29 Modified: 3 Dec 2020 14:28
Reporter: Rob Wagner Email Updates:
Status: Duplicate Impact on me:
None 
Category:MySQL Router Severity:S1 (Critical)
Version:8.0.22 OS:Red Hat
Assigned to: MySQL Verification Team CPU Architecture:x86

[1 Dec 2020 21:29] Rob Wagner 
Description:
Users cannot retrieve more than a handful of rows with 8.0.22.  Errors in the log:

2020-12-01 12:55:31 routing DEBUG [7f0862c80700] fd=23 write error: Resource temporarily unavailable
2020-12-01 12:55:31 routing DEBUG [7f0862c80700] fd=23 write error: Resource temporarily unavailable
2020-12-01 12:55:31 routing DEBUG [7f0862c80700] fd=23 write error: Resource temporarily unavailable

Downgraded to 8.0.21 and problem is resolved.

Also reported here:
https://www.onooks.com/mysql-router-failing-with-write-error-resource-temporarily-unavaila...

How to repeat:
Don't have a good test case.  If we run a query that pulls back ~2000 rows from within the same network, there is no problem.  If the client is outside the network, the client hangs and we see the above errors in the mysqlrouter.log.

Downgrading to 8.0.21 resolved the issue.
[3 Dec 2020 14:09] MySQL Verification Team 
Hi,

Thanks for the report. This is a duplicate of a bug#101406 

all best
Bogdan
[3 Dec 2020 14:28] Rob Wagner 
That is great.  Encouraged to hear you have a useful testcase.