[MDEV-24773] slave_compressed_protocol doesn't work properly with semi-sync replication Created: 2021-02-03  Updated: 2023-11-01  Resolved: 2021-04-26

Status: Closed
Project: MariaDB Server
Component/s: Replication
Affects Version/s: 10.3, 10.4, 10.5
Fix Version/s: 10.3.29, 10.4.19, 10.5.10

Type: Bug Priority: Critical
Reporter: Nilnandan Joshi Assignee: Sujatha Sivakumar (Inactive)
Resolution: Fixed Votes: 0
Labels: None

Issue Links:
Problem/Incident
causes MDEV-32655 rpl_semi_sync_slave_compressed_protoc... Closed
Relates
relates to MDEV-32551 "Read semi-sync reply magic number er... Closed

 Description   

slave_compressed_protocol doesn't work properly with semi-sync replication. When it is enabled, It leads to intermittent SBM (Slave Behind Master) spikes and sometime gives below error. 

2021-01-29 15:34:40 11 [ERROR] Read semi-sync reply magic number error
 
2021-01-29 15:34:50 9 [Warning] Timeout waiting for reply of binlog (file: master-bin.000001, pos: 479), semi-sync up to file master-bin.000001, position 329.
 
2021-01-29 15:34:50 9 [Note] Semi-sync replication switched OFF.

Looks like this is upstream bug. https://bugs.mysql.com/bug.php?id=86230
"The receiver thread for semisynchronous replication was not able to receive acknowledgements from slaves that used compression of the master/slave protocol (slave_compressed_protocol = ON) "

 Comments   
Comment by Sujatha Sivakumar (Inactive) [ 2021-02-08 ]

Hello Andrei,

Can you please review the fix for MDEV-24773

Patch: https://github.com/MariaDB/server/commit/4f9c5a8cf545133c3d29c0de3f7e2e57564607f2

BuildBot Test: http://buildbot.askmonty.org/buildbot/grid?category=main&branch=bb-10.3-sujatha

Thank you

Comment by Andrei Elkin [ 2021-04-21 ]

The patch looks good to appove. Please find one note of a general character on github. Thank you for creative efforts and, naturally, to Venkat !

Comment by Sujatha Sivakumar (Inactive) [ 2021-04-26 ]

Fixed is implemented in 10.3.29.

Patch was cherry-picked to higher versions and tested on buildbot.
No merge conflicts were observed.

10.4 patch: https://github.com/MariaDB/server/commit/a2ba707c3feb4870ca7760abaef8dc3389f8da26
10.5 patch: https://github.com/MariaDB/server/commit/f19408e8519071e9410124f8ec4e5b7733d334e3

Generated at Thu Feb 08 09:32:33 UTC 2024 using Jira 8.20.16#820016-sha1:9d11dbea5f4be3d4cc21f03a88dd11d8c8687422.