I've been a long time unRAID user and have had split level set up in various ways on my user shares since the beginning.  The argument for split level was mainly around keeping similar files together, allowing disks to remain spun down in the case of movies being split into multiple files, etc.

 

However now I am questioning why it is even needed at all... performance from accessing multiple files across different disks in the array is very good, and I no longer allow any of my disks to spin down (I hate the spin up delay)... so I question why should I even bother worrying about this and should I not just set all of my shares to use a split level of 99 so unraid can put files wherever it wants?  I use the high water file allocation method which generally groups files copied to the array around the same time together anyway (not that it matters).

 

I've been working through a RFS to XFS migration and as a result of moving content back and forth between disks my existing split level arrangements have gone out the window anyway so this is what triggered the thought... I do also make use of included/excluded disks so again, I can't see any real valid use for split level anymore?

 

Thoughts anyone?

Sounds like you've done a good job of talking yourself out of using split levels, and that's fine. I'm not sure if you are implying no one should ever use split levels, or really what you are asking.

 

If you just want approval, then the scenario you have laid out (no spindown, highwater, don't really care which physical drive the file is on) is perfect for letting unraid put files wherever.

 

I'm a little more OCD, I need to know which file sets are on which disks. No other reason than just because.

Not implying that at all... but I think you answered my question and gave me the "approval" I was looking for :-)

 

So other than to just be very particular about what is stored where, you have confirmed my understanding that based on my specific scenario I shouldn't expect any performance-related issues or long-term file system issues.

 

Thanks!

Initially, I had set unraid to spin down the drives. As you can imagine, whenever I tried to play something in xbmc/kodi, the drive hosting the file would be spun up. Naturally, having the subtitle file on the same drive meant that only one drive was spinning while watching a movie rather than two. That's where the split level came in handy.

 

Fast forward a few years, I got annoyed with the delay of spinning drives up, and read some articles talking about how the constant parking and unparking of the head can cause issues in the long term for some hard drives,  so I decided to avoid spinning down altogether.

 

Sure, my electricity bill is probably higher, but not by that much, and the drives are happy spinning along 24/7. I have drives that have been spinning for almost 6 years non stop and going strong.

 

So now, the split level is no longer a concern for me. All new shares created have everything scattered all over. But it doesn't matter. It is unraid's job to host the files and protect them. I don't care where each file is located

Initially, I had set unraid to spin down the drives. As you can imagine, whenever I tried to play something in xbmc/kodi, the drive hosting the file would be spun up. Naturally, having the subtitle file on the same drive meant that only one drive was spinning while watching a movie rather than two. That's where the split level came in handy.

 

Fast forward a few years, I got annoyed with the delay of spinning drives up, and read some articles talking about how the constant parking and unparking of the head can cause issues in the long term for some hard drives,  so I decided to avoid spinning down altogether.

 

Sure, my electricity bill is probably higher, but not by that much, and the drives are happy spinning along 24/7. I have drives that have been spinning for almost 6 years non stop and going strong.

 

So now, the split level is no longer a concern for me. All new shares created have everything scattered all over. But it doesn't matter. It is unraid's job to host the files and protect them. I don't care where each file is located

 

I agree with you completely!  Drive spin up delay is so annoying, not just for watching movies but even for regular file browsing.  And I too also did my research and concluded the same regarding constant spin up/spin down of drives - I also have disks that have been spinning for 6 years plus.  Saving energy (and money) has always been a concern but with an array consisting of mostly WD reds, with 10 disks the power draw on average for me is less than 40W more to have everything spun up vs spinning up and down based on how often I write to the array.

 

Thanks for chiming in on this...

Agree -- if your drives are always spinning, then there's no real reason to worry about the split level.    A lot of folks are OCD about what files are on which disk ... but the reality is it makes NO difference (except for avoiding spin-up delays); and in fact somewhat misses the key advantage of user shares => which are designed to "hide" the underlying disk structure.

 

I don't leave my disks spinning 24/7, but I do have all the drives in any given share set as a "spin-up group", so when one spins up, they all do ... and they don't spin down for 3 hours.    Basically this means that once I start using the system, there's no delay except for the initial access.

 

I decided to avoid spinning down altogether.

Sure, my electricity bill is probably higher, but not by that much, and the drives are happy spinning along 24/7. I have drives that have been spinning for almost 6 years non stop and going strong.

To put some numbers on it...

 

The spec sheet for the drives in my server say they're 9W average power consumption. I have eight of them.

The rule of thumb is that for most of the US: something running 24/7/365 costs you $1/yr/w.

So, each of the 8 drives in my server costs me $9/yr, for a total of $72/yr, or $6/mo.

 

Yeah, for that, I'll just leave them spinning.