Hello,

I have following Maxscale configuration for read-write splitting the load between maria1 and maria3; maria2 is used for backup purpose only so it has the last priority and weight=0.

This configuration is used for a Galera Cluster of 3 MariaDB nodes in 10.1 version branch.

I'm using Maxscale 2.1.4 and I don't know why but the SELECT statements go all to maria1, and none to maria3.

[RW]

type=service

router=readwritesplit

servers=maria1,maria2,maria3

max_slave_connections=1

router_options=slave_selection_criteria=LEAST_GLOBAL_CONNECTIONS,master_accept_reads=true

user=mastersplit

localhost_match_wildcard_host=1

weightby=myweight

[maria1]

type=server

address=10.181.111.74

protocol=MySQLBackend

priority=1

myweight=1

[maria2]

type=server

address=10.181.111.32

protocol=MySQLBackend

priority=3

myweight=0

[maria3]

type=server

address=10.181.111.14

protocol=MySQLBackend

priority=2

myweight=1

The command

SELECT @@hostname

is always returning the first node's name even without the option master_accept_reads.

I also tried with :

router_options=slave_selection_criteria=LEAST_CURRENT_OPERATIONS,master_accept_reads=true

I attached a screen cap of the observed load of queries on all 3 servers grouped by query type.

Node 1 is getting all the load from maxscale and node 3 isn't even getting a part of the SELECT load.

The strange thing this is that maxscale's RW Split service shows that 49% goes to slaves :
Number of queries forwarded to master: 17530969 (50.20%)
Number of queries forwarded to slave: 17392880 (49.80%)
Number of queries forwarded to all: 5062417 (14.50%)

But as master_accept_reads=1, it seems that master=master and slave=master too without the weight being taken into account because there isn't event 10% load going to node 3.

Expected behavior would be :75% of the load going to master (50% as master + 25% because master_accept_reads=1 and weight is 1/2) and 25% of the SELECT load going to slave node3.