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EC2 instance for Radiance Five phase method

asked 2018-05-08 20:06:53 -0600

basdav's avatar

updated 2018-05-22 11:57:55 -0600

Hi all,

Can anyone advise a convenient instance to run Five phase method Radiance simulations? Last year we tried for a while with the elegible free Tier t2.micro but at some point the simulations get so heavy and it runs very slow. Is there another option that someone has tried and found it works well and its a good balance in terms of cost as well?

I'd appreciate your help


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answered 2018-05-09 11:56:55 -0600

I've used a range of different instance types for 5 and 3 phase calculations. The five-phase method is easily parrallelized (using the -n option in rcontrib), so I tend to use one with lots of CPUs. If you're doing an illuminance calculation I'd recommend using the compute optimized instances. If you're doing annual renderings I'd suggest using a memory optimized instance and copy the matrix files to the instance's SSD drives.

I almost exclusively use the spot instances, which risks having your simulation shut down mid-way, but usually results in a 70-90% savings on rates. With a little experience, you learn which instance types are likely to spike and when. For example weekends and holidays are a good time for spot instances.

Also, I recommend using the alarm to shut down your instance when the CPU drops below 0.5%. But make sure you're putting your results onto a network attached drive, as the instance's drives are lost when they're released. I also highly recommend using Amazon's EFS service for storage.

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Thank you so much for your reply, very good points indeed, I was kind of afraid of trying the spot instance but I think I'll give it a try. Thanks again!

basdav's avatar basdav  ( 2018-05-12 03:58:29 -0600 )edit

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Asked: 2018-05-08 20:06:53 -0600

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Last updated: May 09 '18