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Drive storage rates, does this sound right?

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I have a Geovision 8 cam system capturing 15fps/cam (120 frames total).

 

I have the store setup to record round the clock from 9am to midnight, and motion only from midnight to 9am.

 

This unit is getting around 15 day's storage before filling up - and I have 4 200gb drives in raid 5 (580ish GB effective).

 

So it's working out to be around 4.5GB/cam/day. Does that sound about right? I am using simple 420 line domes at this store.

 

The customer has stated a desire to have the storage save to around 30 days on the HD. Are there tweaks to make the recordings smaller HD wise, other than to increase the motion only setting?

 

-WC-

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Tune the "Recording quality" slider to 3 (or 2, as it mackes very little quality difference) and you should get an additional 7-8 days.

 

scottj

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why 15 fps per camera when you could get the same "quality at 9? What type compression?

 

The question you ask is already answered in your numbers. If you want to increase days you'll need to convince the customer to live with a lower fps. I guess it goes back to what you sold him when you sold it?

 

MPEG4 does very well in terms of quality and storage.

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Well seems you have it the other way around.

 

Time lapse at night at a slow speed of say 1-5fps, and motion detection during the day. Regardless of how you set up the night time, most color cameras will pixelize under low lighting, especially low lux cameras, and cheap color cameras (eg Bullets), and this will cause continous recording if set to motion detection, on most cameras and DVRs.

 

Best bet would be to do motion detection when you have alot of light as that is when the camera performs at its best, and just time lapse at night, you will find you will get much much more time.

 

And also, like said above, lower the fps and you will get longer either way.

I have a GE DVR 640GB with 10 cameras, at 5fps, on motion only, indoors only though which makes a huge difference, doing almost 6 months of recording. Now, these are also BW cameras which do not experience the same problem with pixelisation as color cameras, and when it is dark inside this location, its pitch dark anyway, so it doesnt record. Just a time comparison.

 

Also, what is your total recording space, as you mentioned raid, isnt that then split in 2? Ssshhhh, Im still learning about raid

 

Rory

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Quick raid primer for Rory:

 

Raid 0: Usually called stripping. Has great speed, zero redunancy. Usually used for two drives. Some raid controllers call this JBOD (Just a Bunch Of Disks)

 

Raid 1: Mirroring. One drive is copied to another in real time.

 

Raid 0 + 1: Stripping and mirroring. Very fast way of redunancy for two drives.

 

Raid 5: One drive out of a set is used for checksum data/redunancy info. 4x250 gb gets you 750 GB of drive space. 6x250 GB gets you 1250 GB. 5x400 gets you 1600 GB, etc.

 

Those are the three most common forms of raid.

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okay thanks

 

Yeah it was stripping i did with the XP software on 2 drives the other day, couldnt remember the name of it ..

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In a PC Based DVR setup with 2 smaller system drives, and larger ones for storage only... would RAID 0 (or 0+1) be worth it on the system drives only?

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Rory, please for the love of god don't use software spanning. It's failure rate is far too high what we use it for. I wouldn't use Raid 0 on two system drives. Maybe two seperate drives each in Raid 0 for speed, or both in 0+1. You won't see radical speed boosts that way but it won't hurt. Raid 0 can help on a drive storing large files (video clips).

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no, used striping, spanning was the other option.

 

But basically, they had 2 drives, and eclipse doesnt have software to do the job, so had to do it this way, they are cheap.

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no choice on the eclipse on that job. Been working fine since then though. Can only tell them if they dont have the money there is nothing else can do.

 

From experience last couple days with Geo, Geo is much more tempormental than the others I have used though.

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Quick raid primer for Rory:

 

Raid 0: Usually called stripping. Has great speed, zero redunancy. Usually used for two drives. Some raid controllers call this JBOD (Just a Bunch Of Disks)

 

Raid 1: Mirroring. One drive is copied to another in real time.

 

Raid 0 + 1: Stripping and mirroring. Very fast way of redunancy for two drives.

 

Raid 5: One drive out of a set is used for checksum data/redunancy info. 4x250 gb gets you 750 GB of drive space. 6x250 GB gets you 1250 GB. 5x400 gets you 1600 GB, etc.

 

Those are the three most common forms of raid.

 

Correction: A part of EVERY drive in the array is used for parity (data redundancy). The amount of total space consumed by parity will equal the size of one drive. The formula for calculating is (N-1)*S where N = the number of drives and S = the size.

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I should have been more clear. Don't use software raid.

 

I agree, don't use software raid. But, also don't use cheap RAID controllers. Controllers such as Promise and Highpoint are actually slower than some software raid controllers. If you are serious about data redundancy, get yourself a good 3ware raid card.

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