Chaos Corona Forum

General Category => Off-Topic => Topic started by: Tue Nguyen tri on 2018-09-09, 04:19:12

Title: How to change Hard drive virtualram?
Post by: Tue Nguyen tri on 2018-09-09, 04:19:12
https://forum.corona-renderer.com/index.php?topic=17892.0
My SSD is 256 GB and it's full when rendering with corona. Because sometime corona need virtual ram from hard drive. So i can't work with other project and preview image in explorer.
But other hard drive has about 100GB free. Do you think we should add new feature: choice hard drive for virtual ram?
Title: Re: How to change Hard drive virtualram?
Post by: sprayer on 2018-09-09, 09:41:37
System disk always  should have free space  for properly running programs, if it will be full then you cannot run programs. Also if corona start using  hdd  it will rendering very slow and may be not stable. Best choice to add  more ram not virtual. You may change disk for store pagefile though
Title: Re: How to change Hard drive virtualram?
Post by: vkiuru on 2018-09-09, 10:24:33
System disk always  should have free space  for properly running programs, if it will be full then you cannot run programs. Also if corona start using  hdd  it will rendering very slow and may be not stable. Best choice to add  more ram not virtual. You may change disk for store pagefile though

To be fair Corona memory handling is pretty poor when using stuff like Forest Pack etc. I have 128Gt RAM and oftentimes find rendering slow down to like 10-15 min/1 pass when rendering at 4k res and all the scattering elements unhidden. Unless it's something else entirely on my end, don't expect miracles just by adding RAM.
Title: Re: How to change Hard drive virtualram?
Post by: sprayer on 2018-09-09, 11:59:15
System disk always  should have free space  for properly running programs, if it will be full then you cannot run programs. Also if corona start using  hdd  it will rendering very slow and may be not stable. Best choice to add  more ram not virtual. You may change disk for store pagefile though

To be fair Corona memory handling is pretty poor when using stuff like Forest Pack etc. I have 128Gt RAM and oftentimes find rendering slow down to like 10-15 min/1 pass when rendering at 4k res and all the scattering elements unhidden. Unless it's something else entirely on my end, don't expect miracles just by adding RAM.
I am just saying what if your scene is seeking free space then it would much faster with RAM than HDD.  Using forestpack heavy scene you should use optimized models(without opacity at leafs)  and materials without refraction. Do not see any benefits comparing to cscatter. less plugins less bugs
Title: Re: How to change Hard drive virtualram?
Post by: Bzuco on 2018-09-10, 09:17:59
You can choice any HDD/SSD drive for virtual RAM in windows settings. It is not corona related. Just set one swap file on SSD with fixed size (e.g. 16384MB) and second swap file on HDD.
I have 16GB ram and 2x 16GB swap files on two SSD. It works great until my RAM is full and in swap files I have no more than 8GB. Render start a little slower, but after few passes corona make some magic and speed is at full 100%.
Troubles start when I render some scene which put more than 8GB into swap files :))) ...then rendering is slow and there is a lot of reading and writing data on SSDs 300-500MB/s.
Title: Re: How to change Hard drive virtualram?
Post by: agentdark45 on 2018-09-10, 10:28:44
Here's an interesting one, what about using an Optane m.2 drive as a dedicated swap drive? Optane has much lower latency compared to traditional m.2 drives - could this be a viable alternative due to ridiculous RAM prices at the moment?
Title: Re: How to change Hard drive virtualram?
Post by: Juraj on 2018-09-10, 13:08:43
Here's an interesting one, what about using an Optane m.2 drive as a dedicated swap drive? Optane has much lower latency compared to traditional m.2 drives - could this be a viable alternative due to ridiculous RAM prices at the moment?

https://www.theregister.co.uk/2016/04/21/storage_approaches_memory_speed_with_xpoint_and_storageclass_memory/

It's 50 times slower than Ram, but still 10 times faster than SSD.

(https://regmedia.co.uk/2016/04/19/latency_table_a.jpg?x=648&y=308&infer_y=1)

But:
It's still very expensive.
A lot of swapping is throttled long before it reaches hardware IO. You know how 3dsMax takes seven years to save 1GB file despite the SSD needing half a second ? I am afraid it could lead to similar result with rendering imho..
But yeah, someone would need to test it at the exact application. Perhaps someone here with Intel Optane drive ?
Title: Re: How to change Hard drive virtualram?
Post by: iancamarillo on 2019-04-19, 04:16:07
any update on this? Im running a small xeon deadline farm. And when I copy files locally loading, parsing, etc. seems faster. Would animation times (10min/frame) see a benefit in a "ram drive" type setup?