Larger single HDD or multiples

[frankred]

At what point (of throughput, individual cameras, etc) does it make sense to add more hard drives instead of a single larger drive?
I ask because I am trying to spec out a replacement server that is from 2011 that uses 2 separate storage drives. I don't want to find out I am limiting performance by purchasing 1 4TB WD Purple instead of 2x 2TB.
Thanks!
John

 

[thejbgc]

Personally I have a Synology system that has 5 HD's. They act as one single large 20TB drive. I do not notice any speed improvements when compared with backing up to a single 4TB external HD.

 

[nayr]

4TB and 6TB are best bang for your buck.. more hdds = more wattage = more cost to operate, less is better for this situation.

 

[frankred]

Personally I have a Synology system that has 5 HD's. They act as one single large 20TB drive. I do not notice any speed improvements when compared with backing up to a single 4TB external HD.

4TB and 6TB are best bang for your buck.. more hdds = more wattage = more cost to operate, less is better for this situation.

Thanks! Milestone spec'ed a server based on a request i put in, and he suggested 2 HDDs. I would have gone with fewer drives until he planted that bug in my head.

7 Panasonic PW502 @3mp, H.264, 10fps
7ACTi Encoder running LPR, MPEG 740x480 10fps

i7 4790, 8GB, 1x 7200rpm 146GB for OS, 2x 7200rpm 2TB for storage,

I want to try it all on my HP Elitedesk 800 i7 4770, 16gb, 128GB SSD OS, 5400rpm 5tb. The easiest way would be to transfer a settings file to import all the cameras so the existing server is online and mine is capturing the same info. If it handles it well, I may just move it into production. If not, I can react when buying a new server.

I haven't been able to get the free time to call them during working hours to ask that question this week.

 

[nayr]

when I benchmarked my wd purple I was able to achieve ~160MB/s iirc pretty easy.. a 4MP camera doing MJPEG @ 20FPS pumps ~4MB/s and thats about the most bandwidth Ive been able to get a camera to output.. You should have no problem putting a few dozen cameras or less on a single disk, performance wise.

the trick tho is nothing else should really access that disk, other than your nvr software.. if you dump recordings out for playback/editing, do it to another disk so any transcoding/editing dont cause your recordings to studder.. you never want your recording disks to come close to reaching max, if it does then its not recording well.

it would also be better to put a single 4TB disk in and leave room for another if you need, instead of filling up all your disk capacity just to get 4TB.. so consider your chassis space as prime, often costs more to add to that than upgrade drive capacity.

 

[frankred]

when I benchmarked my wd purple I was able to achieve ~160MB/s iirc pretty easy.. a 4MP camera doing MJPEG @ 20FPS pumps ~4MB/s and thats about the most bandwidth Ive been able to get a camera to output.. You should have no problem putting a few dozen cameras or less on a single disk, performance wise.

the trick tho is nothing else should really access that disk, other than your nvr software.. if you dump recordings out for playback/editing, do it to another disk so any transcoding/editing dont cause your recordings to studder.. you never want your recording disks to come close to reaching max, if it does then its not recording well.

it would also be better to put a single 4TB disk in and leave room for another if you need, instead of filling up all your disk capacity just to get 4TB.. so consider your chassis space as prime, often costs more to add to that than upgrade drive capacity.

Great info! I agree that space is a prime asset. My PC is SFF, so I can squeeze 2x 3.5" with 1x 2.5" if I unplug/delete the dvdrom. Mini towers cost an extra $300 (ebay off lease and outlet stuff). If my pc can handle the load, I will order a single 4TB purple (my 5TB is a WD green) and either use my SFF or another. If not, I can add drives and decide if I need a newer cpu, and get a mini tower if I have to.

 

[nayr]

in that case put a 6tb purple in it, better to oversize when your constrained for space.. you'll be adding more cameras before you plan for it

 

[alwayson]

Hi Nayr,

I hope you are dong well. Do you have any good source to buy the Purple HDD at? Or does one keep watching the big box and online retailers?

What is a 'good' price for a 6TB WD Purple?

Thank you!
theoxonian

in that case put a 6tb purple in it, better to oversize when your constrained for space.. you'll be adding more cameras before you plan for it

 

[nayr]

I got my last one for ~$200 from AmazonWarehouse, its not the only nvr disk though and I could afford to go without one while the other is being RMA'd.. I tested it well before deploying it.. it said it was blemished in the description but me and 4 of my nerdy friends inspected it and found no blemishes.. go figure, its a chance but it saved me $60

divide terrabytes by price to find the price per terabyte, and compare.. you'll find the best price right now is 4TB but 6TB is close 2nd and if your pressed for space the cost is worth it now.

 

[frankred]

.

•

 

[Kawboy12R]

2 HDs is a bit overkill for the camera load you want. One will handle it just fine but splitting the load allows the system to do other things like database compaction, video export, etc with less possible impact on recording, particularly if all cameras are likely to be recording at once. Also, if one drive goes down, you only take out half your cameras and can quickly move storage to the other drive without a large performance hit. Sooo, one is fine but two is better. Not necessary but a bit better.

There's no thrill like overkill. I learned this phrase from a buddy in the military but it has other applications as well.

 

[wcrowder]

http://www.amazon.com/dp/B01C2PWLZW/ref=twister_B00NPYYXGK?_encoding=UTF8&psc=1

 

[alwayson]

Hi @nayr and friends,

I hope you are doing well. I am looking for a HD for my NVR. Can you please tell me if any of these HDs are a good deal please?

1) 4 TB Western Digital Purple 3.5" SATA III 5400 RPM Surveillance Hard Disk Drive (WD40PURX) for $130

2) 6 TB Seagate Surveillance HDD 3.5" 7200 RPM SATA III Internal Hard Drive (ST6000VX0001) $220

3) 6 TB Seagate NAS HDD 3.5" SATA III 7200 RPM Internal Bare Hard Drive (ST6000VN0021) for $220

I really appreciate your help.

Please let me know as soon as possible, so I don't miss out!

Thank you,
Oxonian

 

[Kawboy12R]

Where are 4TB Purples going for $130? I'll buy some.

 

[frankred]

They are $120 used/refurb on Amazon. Not sure if that is worth the $20 or not...
At 6tb, I would pay the extra $30 to get a Purple 5400rpm drive over a 7200rpm drive for the heat factor in an NVR.

 

[Kawboy12R]

Ah, not really interested in refurbs. New ones can be dodgy enough with improper shipping and handling.

 

[alwayson]

They are $120 used/refurb on Amazon. Not sure if that is worth the $20 or not...
At 6tb, I would pay the extra $30 to get a Purple 5400rpm drive over a 7200rpm drive for the heat factor in an NVR.

I'll post the link during my lunch break, as I cannot do it from my phone. I am pretty sure they are not refurbished.

Are you suggesting that I should get the 6TB 7200 Seagate compared to the 4TB Purple?

I will use it in the NVR.

Is one 4gb or 6gb sufficient for home use, or do I need 2?

Thank you!
Oxonian

 

[alwayson]

Here is the link. Sorry for the delay, I just got home

http://www.newegg.com/Product/Product.aspx?sdtid=9057211&SID=2a54a5386fd311e6893682b003bfdcdb0INT&AID=10440897&PID=1225267&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-cables-_-na-_-na&Item=N82E16822236659&cm_sp=