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Handruin

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What is the theory of increasing number of drives vs. % of capacity on max. RAD performance?
If I have six drives in RAID 6 and add a seventh, will that cause more CPU load from the parity calculations?
At this point it is about 60% full and would then be about 50% full, but usage will increase in the future.
There are far too many factors to give a generalized statement on that question. If you're doing mostly large monolithic file transfers, adding more drives could help because you're spreading the load over multiple drives. The parity calculation shouldn't even be noticeable in a healthy array. Are you using software raid or is it done by a raid card? If it's done by a raid card, I wouldn't even worry about going from 6 to 7 drives with regards to parity overhead. I'm running two sets of 10 drives in software raid 6 and it's not even a concern.
 

LunarMist

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There are far too many factors to give a generalized statement on that question. If you're doing mostly large monolithic file transfers, adding more drives could help because you're spreading the load over multiple drives. The parity calculation shouldn't even be noticeable in a healthy array. Are you using software raid or is it done by a raid card? If it's done by a raid card, I wouldn't even worry about going from 6 to 7 drives with regards to parity overhead. I'm running two sets of 10 drives in software raid 6 and it's not even a concern.
It is in the Synology with the quad-core Xenon. I suppose it doesn't matter too much.
 

Stereodude

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What is the theory of increasing number of drives vs. % of capacity on max. RAD performance?
If I have six drives in RAID 6 and add a seventh, will that cause more CPU load from the parity calculations?
At this point it is about 60% full and would then be about 50% full, but usage will increase in the future.
Why would more drives cause the parity calculation to be more complex?
 

Howell

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What is the theory of increasing number of drives vs. % of capacity on max. RAD performance?
If I have six drives in RAID 6 and add a seventh, will that cause more CPU load from the parity calculations?
At this point it is about 60% full and would then be about 50% full, but usage will increase in the future.
It would add no more load to parity calculations and would spread the work over more spindles. Win.
 

LunarMist

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Synology has a DX1215 expansion unit for the DS3617xs, etc. that connects by a fairly short inifiband cable.
Does anyone have experience with this type of cable or expanding the NAS? I would create a separate array of lower speed drives so the impact of the external interface is unimportant, but I would like to run a 2m cable between the NAS and expansion box. Thanks.
 

Handruin

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If it's infiniband the cable might conform to an SFP+ or QSFP+ depending on the speed. Those connection types are a standard and depending on how far you need to run a cable you will have shorter limits using DAC copper cable vs going with fiber optics.

Can you provide the specs for the Infiniband interface on the DX1215?
 

Handruin

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I tried to look it up and it does not appear to be an SFP+ connection. It's some kind of Infiniband sata x4 cable that I'm unfamiliar with.
 

LunarMist

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I tried to look it up and it does not appear to be an SFP+ connection. It's some kind of Infiniband sata x4 cable that I'm unfamiliar with.
It appears to be an SFF-8470, a trapezoidal type of connector. I'm not familiar with it, only SFF-8087 and SFF-8088.
https://www.servethehome.com/wp-content/uploads/2011/01/SFF-8470-Infiniband-CX4-Connectors.jpg
https://www.servethehome.com/sas-sa...8088-8470-8482-8484-single-device-connectors/

I suppose I can order and take a chance.
 
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LunarMist

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Uh, maybe you only have two 10gb devices.
Then what would be the need for a switch? The NAS have GbE ports as well. I'm sure some normal single users would find a use, but it wouldn't work for me. :lol:
Of course in a datacenter the incoming 10GbE is distributed to the groups or individuals of gBE users.
 

Handruin

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It's useful if you have multiple computers with 1Gb connections that connect to one or two NAS devices with 10Gb connections assuming the NAS is capable of dealing with the IO.
 

Stereodude

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Then what would be the need for a switch? The NAS have GbE ports as well.
Maybe the two systems with 10gb need to talk to each other over a very high bandwidth link and still talk to other systems and you don't want the headache of connecting the two 10gb systems directly to each other and also to a 1gbE switch and have to manage which interface they use for transferring data in every program / protocol.
 

LunarMist

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I'm sure there are a lot of possibilities, but I'd rather have more ports. Four would be the least, but eight would be nice for future proofing.
I really should be buying a new monitor before the NAS updrages.
 

Stereodude

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I'm sure there are a lot of possibilities, but I'd rather have more ports. Four would be the least, but eight would be nice for future proofing.
I really should be buying a new monitor before the NAS updrages.
For me, I only need two SPF+ once I initially go 10gb. The MicroTik would work. Sure, it doesn't have any room for expansion, but it's cheap enough that by the time I need to add a 3rd 10gb computer (not anytime soon) there will likely be other cheap fanless switch options with more SPF+ ports that cost likely less than the TP-Link.
 

LunarMist

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I have two computers and two NAS with SFP+ at this point, so the main reason for a switch would be to use more NAS or more computers.
I'm not sure about the future of that interface.
 

Handruin

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I doubt you will see SFP+ interface go away any time soon. It's quite versatile by allowing you to select direct attached copper cables or to go to fiber optic for longer distances and improved signal to noise because there is no electrostatic interference. Performance, latency, and power consumption is also better at the receptacle ends when compared to an RJ45 connection type.
 

LunarMist

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I doubt you will see SFP+ interface go away any time soon. It's quite versatile by allowing you to select direct attached copper cables or to go to fiber optic for longer distances and improved signal to noise because there is no electrostatic interference. Performance, latency, and power consumption is also better at the receptacle ends when compared to an RJ45 connection type.
Thanks. I decided on the cheap route and added the 5-pack USB to the backup NAS.
 
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Agree on the SFP+, multi-interface cards are cheap enough that with small installs you can bridge between devices and skip switches altogether if you like.
 

LunarMist

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My brains are exploding trying to find a workaround for the encrypter.
The eternal QNAP has horrible performance <50MB/sec. with the volume level password. I cannot use something like the Truecrypt since it craps out when larger files are created.
Is there some other tool, maybe a container that increases size as needed without the requirement to be static?
 

Handruin

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My brains are exploding trying to find a workaround for the encrypter.
The eternal QNAP has horrible performance <50MB/sec. with the volume level password. I cannot use something like the Truecrypt since it craps out when larger files are created.
Is there some other tool, maybe a container that increases size as needed without the requirement to be static?
Sounds like you need a thin-provisioned filesystem that you can extend over time and has been encrypted. I can't help with QNAP devices; I've never used one of their products.
 

LunarMist

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I want to pull 5 drives as a group and store them offsite. Maybe the UX was a mistake, but I wanted to make some use of the extra drives.
The only other option is to use the 5 in the Synology, but then I cannot expand the main array past 7.
QNAP does not support encrypted folders for some reason, not that it would help in this case.
 

Handruin

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Are these 5 drives part of some raid set? Are they just JBOD?

I don't know what you're referring to for the UX being a mistake.

Buy a larger array or build your own and use a basic filesystem.

Encrypt the data at the OS level if the array doesn't support it.
 

LunarMist

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Are these 5 drives part of some raid set? Are they just JBOD?

I don't know what you're referring to for the UX being a mistake.

Buy a larger array or build your own and use a basic filesystem.

Encrypt the data at the OS level if the array doesn't support it.
It should be RAID 5. The stupid NAS is wimpy for encryption and surprisingly worse on the eternal UX500P.
 

Handruin

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Is it hardware RAID5 or software? If hardware, you could have a problem if you need to restore the drives from your offsite and can't find the right hardware to connect them to. I'm not surprised the performance is crap.
 

LunarMist

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Is it possible to rotate a whole set of drives in and out of a NAS or will there be a problem with the array that is returned after the other is used? That may be the simplest solution.
 

LunarMist

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Is it hardware RAID5 or software? If hardware, you could have a problem if you need to restore the drives from your offsite and can't find the right hardware to connect them to. I'm not surprised the performance is crap.
That is a good point! For now I'm hoping of course that there is no catastrophe that destroys the home hardware. If necessary then buying some hardware will not be the main issue. Obviously it is not feasible in the long term, but may be fine until the summer of 2020.

I am working with the Verano Crypt, which has an expansion function. One container is 9TB and is increasing to 14. This is my last attempt without buying additional drives.
 

LunarMist

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The file size limit is around 16TB. I wonder if that is normal for a file on a NAS or something of a QNAP issue? Two 14.2 TB files are not bad though.
 
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