Disk I/O for Media Server

[jmcguire525]

I'm trying to plan my storage pool for a media server that handles Plex and Channels DVR for multiple users. During peak hours there may be 10-15 DVR recordings (writes) and 10-15 Plex streams (reads) along with additional writes from Sonarr/Radarr going on simultaneously.

From my understanding HDD random Read/Write performance is usually calculated with small files, whereas all of my I/O will be larger files with 1M blocks, so I'm not sure if the low numbers from CrystalDiskMark apply here.

Right now my options are 16 disks (8 wide RaidZ2 x2), or 15 disks (5 wide RaidZ2 x3 + hot spare). Do I need the third VDEV to prevent any I/O bottleneck? Note: all apps and transcoding run on a separate all SSD Pool.

Specs:

• MB: ROMED6U-2L2T
• CPU: EPYC 7443P
• RAM: 192GB 2933Mhz ECC
• Drives: Exos X18 14TB

 

[AVB]

You are running way more horsepower than I but are still asking a lot depending what resolution and audio you are transcoding to for distribution. My server (see my sig) can do 3 1080P blu-ray ISOs simultaneously maybe more but I only have 3 HDTVs to test it with. You should be able to go well past that but 30 users at once I'm not sure about since that is far beyond anything I have seen let alone tried myself.

Good luck and let us know how it works out.

 

[Davvo]

I suggest you reading this resource in order to understand how pools work and which layout is the most suited to your needs.

https://www.ixsystems.com/wp-content/uploads/2022/02/ZFS_Storage_Pool_Layout_White_Paper_February_2022.pdf