Hi.

First post.  Unraid virgin.  Please be gentle.......!!

 

I am a 'home' enthusiast with enough knowledge and skill to be dangerous!  Have licensed Unraid for a basic setup.

 

I have re-purposed an old PC running a 2500K with 16GB memory, 1Gb NIC, 8 x SATA onboard (4 x 3Gb/s and 4 x 6Gb/s) .  The case is a large Akasa in which there are 9 x 3.5 drive bays in which I have added 3 x 8TB Ironwolf drives and 2 x 256GB Samsung Pro SSD's as cache.  Running of a USB 2.0 Sandisk Cruzer disk (following recommendations I found in here).

 

Admission: Never really got on with 'Linux' before (attention span of a gnat!) so I was determined to persevere with the initial 'trail' of Unraid to see if I could set it up asa media server - SONARR, RADARR, SABNZBD, EMBY.  So I made a few mistakes along the way with not understanding fully cache setup, 'MOVE' etc.  Nothing major, but it resulted in one or two amber triangles on the shares as files got let behind on different disks/caches as I did different set ups.

 

So........

 

Although there is still much to get to grips with, I set up two cache pools with a drive in each (and attached to the 6Gb SATA ports) because there will be nothing on the cache that I could not get back to if a cache failed.  I am not planning on running VM's.  Now that I have everything set up and running OK (in my mind), I found that the normal read/write to/from the array is well over 200 MB/s.  When the parity check run it often starts up at about 270MB/s and stays well above 200 for the complete check.

 

Now given the purpose of the Unraid for media duties, and given that my network is a 1Gb home LAN, the array speed is far faster than the LAN speed and my LAN saturates before the array runs out of steam. 

 

Hence my question- if the array outperforms my LAN, and given my use-case, is there any need for a cache at all?

Edited August 2, 20223 yr by Bob Corless

Technically nothing wrong with it, the Docker services might chug like they were on an old HDD-based PC though because they are... for that it's the random read/write speeds that matter, and HDDs are just bad at that.

Makes sense.  Thanks.

Also obviously your drives will rarely spin down since things will constantly be writing to at least some of them if that matters to you.