Purpose of multiple storage drives if you don't have enough data to fill them

[cryptothedog]

I have seen a lot of people on here that have 4 or 5 storage devices and one cache drive but not nearly enough data to fill them and the data is spread out between all of them....Is there a reason why you would go with multiple storage drives (with the exception of parity) as opposed to just one really large hard drive and one large cache drive (since it is much faster than storage). Is it a performance thing to spread them out across multiple drives in the array? I have about 4tb of data and have a few random 1tb drives that house the data. Is there any reason why I shouldn't just go buy like 2 10tb drives (for parity reasons) and have like 1 large cache drive and that's it to run things off of?

Edited November 30, 2021 by cryptothedog

[whipdancer]

A lot of times, people start with what they have on hand - several smaller drives.

[ConnerVT]

Or, you just can't stand to see all of those empty drive slots in your case.  😝

[trurl]

I usually recommend fewer larger drives. Best to keep some free space on all drives, but no good reason to have lots of drives with little on them.

 

Each additional disk takes additional hardware to connect, at some point additional license, most importantly, each additional disk is an additional point of failure.

[Squid]

Another reason (that I don't agree with) is that some people prefer to have a setup where on any given drive, only a certain media type is present.  Movies on disks 1-3, TV on disks 4-5 etc

 

[cryptothedog]

18 minutes ago, Squid said:

Another reason (that I don't agree with) is that some people prefer to have a setup where on any given drive, only a certain media type is present.  Movies on disks 1-3, TV on disks 4-5 etc

 

Isn't that what the folders created by the shares are for? To organize stuff? lol

Edited December 1, 2021 by cryptothedog

[Frank1940]

Today, HD drive capacity has become insanely large.  (I believe is reached 18TB!)   There is a thought process which every Unraid user should go through.  Basically when deciding to build an Unraid server, they should be looking at two things: 

1. What am I going to be storing on this server?
2. How fast do I expect my data requirements to grow?

The first question is very simple for most people to answer.  The second one is real tough one.  Modern HD's in Unraid service will have a expected service life approaching five years or, perhaps, a bit more.  So if you expect to generate 5TB of new data a year, you need to plan for an initial store capacity of 25TB.  If you are looking at 3 data drives and one parity drive.  You should size your parity drive at 8-10TB.  Start with one data drive and plan to add the second when the first drive is about 75% full.  Picking the 75% point allows one to shop for sales. 

 

By the time, your array of 3 data drives is nearly full, you can be expecting that some of the drives may be reaching their end-of-life.  So you replace parity with a larger drive and, as required, you upgrade the data drives. OR you could add another data drive to the array.  But you have set yourself up with a plan that makes sense in the long term. 

 

By the way, the failure rates are large capacity HD is about the same as small capacity drives.  So an array with fewer drives will always have fewer problems than one with more drives (on a statistical basis)!   (Your mileage may vary...)

 

[cryptothedog]

6 minutes ago, Frank1940 said:

Today, HD drive capacity has become insanely large.  (I believe is reached 18TB!)   There is a thought process which every Unraid user should go through.  Basically when deciding to build an Unraid server, they should be looking at two things: 

1. What am I going to be storing on this server?
2. How fast do I expect my data requirements to grow?

The first question is very simple for most people to answer.  The second one is real tough one.  Modern HD's in Unraid service will have a expected service life approaching five years or, perhaps, a bit more.  So if you expect to generate 5TB of new data a year, you need to plan for an initial store capacity of 25TB.  If you are looking at 3 data drives and one parity drive.  You should size your parity drive at 8-10TB.  Start with one data drive and plan to add the second when the first drive is about 75% full.  Picking the 75% point allows one to shop for sales. 

 

By the time, your array of 3 data drives is nearly full, you can be expecting that some of the drives may be reaching their end-of-life.  So you replace parity with a larger drive and, as required, you upgrade the data drives. OR you could add another data drive to the array.  But you have set yourself up with a plan that makes sense in the long term. 

 

By the way, the failure rates are large capacity HD is about the same as small capacity drives.  So an array with fewer drives will always have fewer problems than one with more drives (on a statistical basis)!   (Your mileage may vary...)

 

Great insight! Thanks, I hadn't really thought of it like that. I was mainly just curious if there was some sort of performance benefit or if people just liked storing random stuff on random drives...still doesn't make sense for the ones that have like 6 drives and 10% of each is full.