More Cores or higher Clock Speed?

[starcat]

How multithreaded is unRAID, i.e. what is better having more cores or higher clock speed? I.e. which one of those CPUs is a better match for a really maxed out unRAID system:

 

Q8300 Core 2 Quad with 2.5Ghz (4MB L2-Cache) or

E8400 Core 2 Duo with 3Ghz (6MB L2-Cache)

[BryantD]

unRAID can only use a max of 2 cores but a single core works just fine.

[Joe L.]

What do you mean by "maxed-out" ??

 

If you just mean "a lot of disks" a single lowly pentium-1 would probably work as well as almost anything else.  Most everything above that should work just fine.  The only time a second core will be useful is if you are running vmware or something like it added onto the unRAID server.  (The vmware process can use the second core)

 

For stock unRAID, one core is plenty and usually only a few percent busy.

 

You will get a better answer if you describe how you will be using your server.

 

Joe L.

[WeeboTech]

unRAID can only use a max of 2 cores but a single core works just fine.

 

I don't know if this is exactly true.

The wording implies that unRAID is limited to use of a max of 2 cores.

 

The linux environment itself will make use of all cores available.

Therefore, The unRAID environment will probably use as many cores as available

The unRAID daemons and other unRAID applications may not make use of all cores simultaneously, but other linux applications in the unRAID environment may use them.

 

Installing a dual core and a quad core will probably reveal little performance variation unless you are adding other applications onto the unRAID environment.

Torrent, upnp, slimserver, vmware, etc. etc.

 

For the regular unRAID environment a 2ghz or better dual core processor will suffice.

unRAID will run fine on a single core 2ghz celeron.

It has been proven to run fine on a single core 1ghz celerom-M.

 

 

If it were my choice between CPUs as noted below.

I would choose the E8400 Core 2 Duo with 3Ghz (6MB L2-Cache) for it's lower power utilization.

I would try to govern the cpu down to lowest clock around 2ghz

 

I use a 2.66ghz duo core 2. I recompile the kernel and clock it down to 1.6ghz with some tools.

I only bought it because it was a great price for a used CPU that I may reuse one day in future.

[starcat]

Hi guys, thanks for your replies. By maxed out I mean Supermicro X7SBE with IPMI processor, 8GB ECC DDR-800 memory, 20+1 disks with the current beta, 64bit CPU, two Supermicro AOC-SAT2-MV8 controllers. I absolutely need a 64bit CPU which rules out Celerons and Pentiums as I am considering going with Solaris/ZFS in case I don't like the performance of unRAID. Solaris/ZFS is extremely threaded by default and will greatly benefit from the 64bit and Quad CPU, I just wasn't sure how unRAID handles things. As I said, I would like to test unRAID first but would need a tmp license for Pro OS supporting all drives. I am willing to benchmark and report here. The X7SBE has two decent Intel 1000CT NICs on board which go up to 95MB/s each. I have a managed HP ProCurve nettwork so that this won't be a bottleneck either. I would like to test NFS performance.

 

I don't plan on running any application on this machine, it is a file server only.

 

I need the fastest drive for parity. I have some SAS 10k 2.5" drives laying around, but I don't think that unRAID supports any RAID controllers? No chances for LSI? It would be pretty cool to have a couple of drives in RAID0 mode hanging off a SAS controller. The parity drive should be the same size as the data drives, right? All data drives are 1500GB Seagate 7200.11's, so it would be difficult to get such single SAS drive to match the size. There also were the SATA based VelocyRaptor but the largest is again 300GB in size.

 

Thanks much for all the great support!

[Joe L.]

Hi guys, thanks for your replies. By maxed out I mean Supermicro X7SBE with IPMI processor, 8GB ECC DDR-800 memory, 20+1 disks with the current beta, 64bit CPU, two Supermicro AOC-SAT2-MV8 controllers. I absolutely need a 64bit CPU which rules out Celerons and Pentiums as I am considering going with Solaris/ZFS in case I don't like the performance of unRAID. Solaris/ZFS is extremely threaded by default and will greatly benefit from the 64bit and Quad CPU, I just wasn't sure how unRAID handles things. As I said, I would like to test unRAID first but would need a tmp license for Pro OS supporting all drives. I am willing to benchmark and report here. The X7SBE has two decent Intel 1000CT NICs on board which go up to 95MB/s each. I have a managed HP ProCurve nettwork so that this won't be a bottleneck either. I would like to test NFS performance. 

 

I don't plan on running any application on this machine, it is a file server only.

 

I need the fastest drive for parity. I have some SAS 10k 2.5" drives laying around, but I don't think that unRAID supports any RAID controllers? No chances for LSI? It would be pretty cool to have a couple of drives in RAID0 mode hanging off a SAS controller. The parity drive should be the same size as the data drives, right? All data drives are 1500GB Seagate 7200.11's, so it would be difficult to get such single SAS drive to match the size. There also were the SATA based VelocyRaptor but the largest is again 300GB in size.

 

Thanks much for all the great support!

Since it is a file-server only, then the CPU is of little importance... anything will do and easily keep up with the server's needs.

 

If you are looking for max "performance" you need to describe a bit more about how the server will be used. 

 

unRAID will NEVER be as fast as a hardware raid server... nor will it be as fast as RAID5 (where it writes to all the disks in parallel, but they can never be individually spun down). 

 

If pure speed is what you need, then look elsewhere or buy the fastest rotational speed disks you can find.  all 10,000 RPM drives will help, unless you saturate one of the busses or the network first.

See this post for details why: http://lime-technology.com/forum/index.php?topic=4642.msg42725#msg42725

 

 

[WeeboTech]

I absolutely need a 64bit CPU which rules out Celerons and Pentiums

 

I don't plan on running any application on this machine, it is a file server only.

 

I need the fastest drive for parity. I have some SAS 10k 2.5" drives laying around, but I don't think that unRAID supports any RAID controllers? No chances for LSI? It would be pretty cool to have a couple of drives in RAID0 mode hanging off a SAS controller. The parity drive should be the same size as the data drives, right? All data drives are 1500GB Seagate 7200.11's, so it would be difficult to get such single SAS drive to match the size. There also were the SATA based VelocyRaptor but the largest is again 300GB in size.

 

Thanks much for all the great support!

 

 

I absolutely need a 64bit CPU which rules out Celerons and Pentiums

 

I would suggest testing it with a spare processor you may have around. unRAID is not 64bit right now.

It does have PAE enabled so you can make use of the 8GB of ram at a slight performance penalty. (Although, Nothing I could measure on my system.)

 

Use the 7200.11 1500GB 7200RPM as a parity drive and test it out.

Also the WD 2TB drives seem to be very fast too.

 

 

In the beta thread there were dd benchmarks of writes with 29-34 MB/s and 80 MB/s or so to a Cache drive.

 

 

unRAID does not support hardware raid controllers at this time. Maybe in the future.

I would not suggest a large SAS or high speed RAID0 array for parity if you are only going to be writing to/from one drive at a time.

You will still be limited to the write speed of the drive you are writing.

 

Where a higher speed of the parity comes into play is when you are writing all around the array randomly and simultaneously.

 

As suggested, if you are looking for write speed, this is not your environment unless you use a cache drive.

If you are looking for massive archival storage, to save power and spinning of idle drives with good read speed and slightly less write speed this will work.

 

[starcat]

Guys, will unRAID absolutely not run with a C2D or C2Q or is it just not necessary to have this kind of CPU? I understand that it can not make any use of it but as I don't have a Celeron or Pentium laying around, wouldn't like to buy an old CPU specifically for a test...

[boof]

Guys, will unRAID absolutely not run with a C2D or C2Q or is it just not necessary to have this kind of CPU? I understand that it can not make any use of it but as I don't have a Celeron or Pentium laying around, wouldn't like to buy an old CPU specifically for a test...

 

It will run fine - just don't expect it to :

 

- make full use of them

- to perform any better because you're running on a C2Q rather than an old celeron.

[WeeboTech]

Guys, will unRAID absolutely not run with a C2D or C2Q or is it just not necessary to have this kind of CPU? I understand that it can not make any use of it but as I don't have a Celeron or Pentium laying around, wouldn't like to buy an old CPU specifically for a test...

 

It will run fine on either of these. a C2Q will waste electricity.

When I tested my system with a celerom 440 and a core 2 duo, it was the same amount of electricity. There was no savings. (I was quite miffed).

Using an old C2D will be fine. There will be times when the other core will assist. Just not very often and it's not required.

Many people here run C2D.

[starcat]

Guys, will unRAID absolutely not run with a C2D or C2Q or is it just not necessary to have this kind of CPU? I understand that it can not make any use of it but as I don't have a Celeron or Pentium laying around, wouldn't like to buy an old CPU specifically for a test...

 

It will run fine - just don't expect it to :

 

- make full use of them

- to perform any better because you're running on a C2Q rather than an old celeron.

This is not what I am expeting. I just want to buy a recent CPU in case I decide to go with something else and not unRAID. I don't have an old CPU laying around waiting for reuse.

 

[WeeboTech]

 

Guys, will unRAID absolutely not run with a C2D or C2Q or is it just not necessary to have this kind of CPU? I understand that it can not make any use of it but as I don't have a Celeron or Pentium laying around, wouldn't like to buy an old CPU specifically for a test...

 

It will run fine - just don't expect it to :

 

- make full use of them

- to perform any better because you're running on a C2Q rather than an old celeron.

This is not what I am expeting. I just want to buy a recent CPU in case I decide to go with something else and not unRAID. I don't have an old CPU laying around waiting for reuse.

 

 

OK then let's get back to the original question.

 

How multithreaded is unRAID, i.e. what is better having more cores or higher clock speed? I.e. which one of those CPUs is a better match for a really maxed out unRAID system:

 

Q8300 Core 2 Quad with 2.5Ghz (4MB L2-Cache) or

E8400 Core 2 Duo with 3Ghz (6MB L2-Cache)

 

Either will work.

Having more cores or very high clock speed does not matter.

The cpu that is a better match for a maxed out unRAID system is whatever modern CPU you are willing to spend your money on which may be more useful in another host should you decide to swap it out.

If you are planning the possibility of going with another product, choose for that product instead of unRAID. unRAID will work with both.

 

I have a 2.4ghz core 2 duo I bought off eBay used in mine.

I am planning to go with an E8600 but only because I want run vmware and have the highest clock speed possible, with the most cache possible, using the least power possible.

[starcat]

WeeboTech, thank you very much!