Why is Vertica using so little memory?

Nicholas_Chamma

Are there any configuration settings I should look at to make sure Vertica is not artificially constrained in any way from using as much memory as is available?

I am finding that Vertica is using surprisingly little memory given how much activity it's handling. We are troubleshooting some basic performance issues, and I want to make sure we have no obvious misconfigurations.

Nick

Abhishek_Rana

Hi,

Memory is a resource & In vertica it is managed by resource pool configurations. Only resource pool configuration parameters can make less memory to get utilized by vertica.

Eg:

Take a look at the concurrency settings as well. If you force Vertica to reserve enough system resources to run 100 queries at once, but you're only running 10, then Vertica's going to be leaving a lot of memory idle just in case more queries come along.



You can check, resource_pools,resource_pool_status,resource_acquisitions tables to know how memory is utilized by vertica & how much memory your transactions
are actually taking. This might give you a clear picture & you might see that, your transactions actually are taking very less memory which in turn is good in performance perspective.

Also, you can check "system_resource_usage" table to see memory_usage,cpu_usage & i/o usage by vertica. It will confirm the actual vertica usages so far.

Regards'

Abhishek