23 April 2021

Unraid 6.9 and Multiple Pools

Unraid OS 6.9 adds multiple pool support to your server's repertoire. Read on to learn why and how to use this new feature.

Multiple Pools

With the release of Unraid 6.9, we have included support for Multiple Pools, granting you even further control around how you arrange storage devices in your server.

So what does this new functionality offer?

Separate Storage for Caching, VMs, and Containers

With a single pool, the same underlying storage for your VMs and containers is being used to provide a cache for your data written to shares. This means when a large copy to a share is taking place, performance in those other applications may suffer. While this may not be noticeable for the average home usage, with power users and multi-user environments, the cost of resource contention is more obvious and overt.

With multiple pools, you can now create groups of storage devices to dedicate to specific functions.

Get More out of your SSDs

Many users leverage SSDs for the cache pool in Unraid 6. This is to increase performance to applications that live in that pool as Docker Containers or Virtual Machines. However, given that most users only have a 1gbps network, those SSDs are never really pushed when it comes to performance. Yet, users are still having to reserve a chunk of space in that SSD pool for the purpose of network file transfer caching. With multiple pools, these users can now set up a pool of HDDs for the purposes of write caching over the 1gbps network, leaving the full performance and capacity of their SSD pool for the applications that can benefit from it the most.

Proper Multiple Pools Set Up

See this video by Spaceinvader One to learn about how to properly set up and use multiple cache pools on your server for the best performance!

Tiered Performance with NVMe

For the most extreme performance use-cases, you can create a pool of NVMe SSDs that doesn't co-mingle with standard SSDs or HDDs. This will allow you to get the full performance out of NVMe which is ideal for high-demand I/O applications or for file caching over a 10gbps network.

Tiered Performance with NVMe

Multiple Pools, please see the official Documentation.

Dedicate Various Pools to Different Shares

For multi-user and/or multi-application environments, it may be best to dedicate different shares to different pools to ensure performance contention doesn't become a problem.

For example, if you have IP cameras in your home or business that are constantly capturing footage, you may want dedicated write caching for them to a specific pool. This allows for your general storage usage performance to not be impacted by those cameras.

Another example use case would be multiple teams of video editors working on different projects. You may want to dedicate a specific pool for one project/group and another for a different project/group to ensure the two groups/projects don't compete with each other for access to resources.

These are just a few examples of how multiple pools will improve performance for all our users and enable new and powerful use-cases for Unraid OS!

Are you using Multiple Pools?

Let us know your use case for Multiple Pools in the Unraid forums!