Mixed brand drives, ssd cache

[ChillyPenguin]

I have 3x 2TB drives of one brand and 2x drives of another brand. From my reading, this will be OK, as FreeNAS will just use the smallest size for each drive. Is this correct?

I plan to run RAIDZ2, so I will be buying one more drive, as I have read an even number of drives is prefered. Does it matter which I use? (the 3x drives are 5900 rpm and the 2x are 7200) Random IO is not much of a concern, this is used for large file storage and streaming video to one user at a time. If I experience a drive failure, I will just replace will 4tb drives, as I will eventually be migrating to those anyway.

Hardware will be Xeon E3-1230 and 16GB ECC RAM. I have a 120GB ssd for a cache drive. Last I checked, it is safe to use a single drive for cache, is this accurate?

Is this setup likely to be able to sustain 100MB/s sequential read over CIFS? I am currently on Openfiler on a Celeron and I can get about 70MB/s over the network, but that is limited by CIFS hitting the CPU too hard.

 

[cyberjock]

I have 3x 2TB drives of one brand and 2x drives of another brand. From my reading, this will be OK, as FreeNAS will just use the smallest size for each drive. Is this correct?

That answer is in our manual and my noobie guide, so I will refer you to there for the answers.

I plan to run RAIDZ2, so I will be buying one more drive, as I have read an even number of drives is prefered. Does it matter which I use? (the 3x drives are 5900 rpm and the 2x are 7200) Random IO is not much of a concern, this is used for large file storage and streaming video to one user at a time. If I experience a drive failure, I will just replace will 4tb drives, as I will eventually be migrating to those anyway.

That's been answered to death, please search the forums.

Hardware will be Xeon E3-1230 and 16GB ECC RAM. I have a 120GB ssd for a cache drive. Last I checked, it is safe to use a single drive for cache, is this accurate?

If you read the manual it says maximum motherboard RAM,and if you read more you'll find that adding an L2ARC isn't helpful for most workloads and if you don't *know* you need it you don't. Again, this is mentioned in my noobie guide and the manual.

Is this setup likely to be able to sustain 100MB/s sequential read over CIFS? I am currently on Openfiler on a Celeron and I can get about 70MB/s over the network, but that is limited by CIFS hitting the CPU too hard.

Most likely, yes. There's plenty of ways to kill your server's performance so I won't assume you've not done something crazy like used a Realtek NIC or something.

 

[ChillyPenguin]

That answer is in our manual and my noobie guide, so I will refer you to there for the answers.



That's been answered to death, please search the forums.



If you read the manual it says maximum motherboard RAM,and if you read more you'll find that adding an L2ARC isn't helpful for most workloads and if you don't *know* you need it you don't. Again, this is mentioned in my noobie guide and the manual.



Most likely, yes. There's plenty of ways to kill your server's performance so I won't assume you've not done something crazy like used a Realtek NIC or something.

Yes, I read your guide, that was the "from my reading" I mentioned. I am using the same MoBo you mention in your guide, but with 16GB rather than 32GB.

I do have 64gb of ecc registered laying around, but that requires buying a new board and CPU. With a planned migration to 6x4TB in about 1 year, would you advise doing that now?

I plan to run Sab, SickBeard, and Plex.

 

[cyberjock]

I do have 64gb of ecc registered laying around, but that requires buying a new board and CPU. With a planned migration to 6x4TB in about 1 year, would you advise doing that now?

If you have confirmed that you have a need, then yes. But, 99% of users don't confirm a need but only think they need it. As I'm not a fan of throwing money at things "because you can" I implore you to determine if a ZIL and/or L2ARC is absolutely necessary. More than 90% of cases it's not and people are just throwing money at things for the e-penis factor.(Hint: You said random I/O doesn't matter in one sentence and then in another used an L2ARC so you are already proviing you dont "need" one.)

I plan to run Sab, SickBeard, and Plex.[/quote]

 

[ChillyPenguin]

If you have confirmed that you have a need, then yes. But, 99% of users don't confirm a need but only think they need it. As I'm not a fan of throwing money at things "because you can" I implore you to determine if a ZIL and/or L2ARC is absolutely necessary. More than 90% of cases it's not and people are just throwing money at things for the e-penis factor.(Hint: You said random I/O doesn't matter in one sentence and then in another used an L2ARC so you are already proviing you dont "need" one.)

I plan to run Sab, SickBeard, and Plex.

[/quote]

Understood, but that is what I am trying to do, confirm the need with the SME. So my question then becomes, will the delta from 16GB to 64GB be noticed when extracting large (30-50GB) archives, reading and writing to the same VDEV? Your guide mentions FreeNAS does use some ram as a short term write cache, is there a way to tune the amount and duration?


What would improve this use case, just more disks?


I keep reading more RAM is better, and the ARC is "most frequently" accessed data. This is not likely to be important to me, as I am concerned about the most recently written data (write and archive, and immediately extract it.)

 

[cyberjock]

ARC is a MFU and MRU system. More RAM always helps. The question is "at what point is the RAM increase providing diminishing returns". The only way to truly answer that is to attempt to use it in such a situation. I will say that 64GB of RAM gives a boatload of headroom in the ARC, which is wonderful. The number of users, how the users use the server etc play an important role in determining how much RAM you want/need.

On the flipside, your bottleneck is almost certainly going to be your 1GB NIC at some point. 100MB/sec or so just isn't "fast" for my definition of it when dealing with 50GB data files.

 

[toadman]

I plan to run Sab, SickBeard, and Plex.

Given the workload you mention, I too suspect your current setup is fine and you would likely see no noticeable performance increase if you upgraded your RAM or anything else. (Well, unless you went to 10Gb Ethernet.)

But I do agree the specifics of your use case will determine the final answer.