3

We are running MariaDB which is a fork of MySQL with NDB cluster engine. The cluster includes one mysql node and two ndb data nodes. While benchmarking the cluster, we are trying to make a bottleneck of CPU and the mysql nodes has 8 cores in total. But mysqld process uses only one to two cores and does not utilizing more than 2 cores. We tried increasing threads and warehouses but that did not help in utilizing all the CPU cores. Is there a way to make this possible. What system variables should I focus on to increase???

Any thoughts or suggestions are appreciated.

| improve this question | |
2

Solution is rather simple: Run mysqld multiple times on the same DB Server !!!.

Assign each mysqld to run on a different port.

The OS will spread the multple mysqld processes across the cores.

UPDATE

You may have to jerry rig some port forwarding using mysql-proxy

Assuming 10.240.35.180 is the SQL node

  • startup mysql on port 3307 in the SQL node
  • startup mysql on port 3308 in the SQL node
  • startup mysql on port 3309 in the SQL node
  • startup mysql on port 3310 in the SQL node

In the mgnt node, set up 4 instances of mysql-proxy

  • mysql-proxy 10.1.1.6 to 10.240.35.180 port 3307
  • mysql-proxy 10.1.1.7 to 10.240.35.180 port 3308
  • mysql-proxy 10.1.1.8 to 10.240.35.180 port 3309
  • mysql-proxy 10.1.1.9 to 10.240.35.180 port 3310

Now place IPs 10.1.1.6 - 10.1.1.9 in config.ini and startup mysql cluster. This sounds like a very major stretch, but it's your only shot at getting mysqld running across multiple cores.

BTW : back on August 10, 2011, someone asked a similar question in ServerFault and gave a detailed explanantion from the MySQL Cluster Team.

Give it a Try !!!

| improve this answer | |
  • No. At present, only InnoDB (since 5.1.38) has parameters capable of engaging multicore activity : dba.stackexchange.com/a/5968/877 – RolandoMySQLDBA Dec 2 '11 at 18:05
  • Is there a way to utilize all cores with one mysqld process? Another item to discuss is as mysql node is a part of cluster. All the nodes are managed by the config.ini file in the NDBD management node, where we list out the mysql nodes under [mysqld] section for each node. The mysql cluster have system parameter "hostname=ip/hostname" but it does not accept a "ip:port". Also could not find a system variable to mention the mysql port. So if I run multiple mysqld servers in the same machine with same ip but different port how do I add this to the config.ini to make the cluster understand this – lampscholar Dec 2 '11 at 18:08
1

I don't know which version of MySQL Cluster is distributed with MariaDB, which may affect the answer.

Generally, to get more throughput from a MySQLD instance connected to a Cluster, we recommend using multiple cluster connections from the MySQLD instance. This is described in this blog : http://johanandersson.blogspot.com/2008/02/mysql-cluster-features-what-they-are.html#multiconnect

This feature is added in mysql cluster 6.3, so if MariaDB distribute that version then you should be able to use it.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.