windows 8 vs windows 10 RAM handling?

[Rhodesy]

Ive been running into some issues with scenes maxing out my 64GB RAM on a windows 8 machine. When Microsoft was doing the free win 10 up date we updated all our PCs but for some reason one of them just wouldnt update so I just left it as windows 8 as it is only a render node. What is strange now that on a few scenes that node fills its RAM and either crashes or just pages and grinds to a crawl but another very similar machine with 64gb RAM and win 10 renders the scene fine with only 40GB recorded in task manager. Im using C4D so I dont know if that has anything to do with it but I was wondering if there was a setting in win 8 that could be changed to give the same RAM handling performance as win 10. Its happened on a number of scenes and with multiple attemps with the only difference being the operating system. Thanks for any pointers.

[Rhodesy]

OK here is some screen shots of the same scene rendered on two almost identical spec PCs with 64GB RAM and no other apps running. You can see the speed hit is quite dramatic due to windows 8 paging a lot more. Windows 10 runs the scene fine at 40GB usage, its initially higher on first pass then drops. Paging is minimal and cpu is pegged at 99/100%. 6 passes in 45mins. Windows 8 is on pass 1 after 1 hour 10mins making that scene un-renderable on that PC. Why would the results be so different on the same scene on the same hardware and is there a way to force windows 8 RAM handing to work more like windows 10? They are both render nodes so there is no local vs network advantage. Thanks

[Nejc Kilar]

This is very interesting...That is a huge difference! I would have thought that W10 would cause you more problems :) Could it be just a messy OS install on that W8? Meaning its been up and running for a few years with all kinds of weird stuff installed on it?

[Rhodesy]

Yes it is a huge difference and all I can put it down to is how the two OS handle the RAM / interface with corona, but its the difference between being able to render a scene and not. On smaller scenes where the RAM isnt pushed it renders fine. The problem node used to be a workstation but I did a clean reinstall when it was retired as a node maybe a 2-3 years ago so it should be pretty clean as there are only a handful of programs on there.

[Frood]

My 2 cents:

Prior to Win10 (we only used NT3.x -> NT 4 -> WinXP -> Win 7) best option to handle high ram usage was to have a manually and fixed pagefile (of about 1x to 2x the size of physical ram). Boxes were always setup like this to avoid page file size changes resulting in high disk usage and low CPU performance. Don´t know if this applies to Win8 as well.

I've done a few tests when migrating to win10 and (without having some evidence at hand) it turned out that it is better to let the system manage the page file. Especially since compressed memory was introduced in Win10, which is activated by default.

Would love to read other's experiences regarding the page file settings.


Good Luck

[Rhodesy]

Thanks for the 2c. That compressed memory sounds like it might have something to do with it. Have tried the manual page size trick you suggested to double the ram 64 to 128gb. Unfortunately no difference although there is only one drive on that machine so there could be a bottleneck somewhere. I've given up though, spent half a night trying to optimise a scene to render out on it but it just snarled up on the first pass after 7 hours. Ran the original less optimised scene on a windows 10 machine the next day and it rendered fine using 80 odd% or the ram according to task manager. When I say rendered fine it was running slower, seemed reasonable to 6 passes then slowed to 3-4 passes an hour but it's better than 1 in 7 hours!

Going to have to admit defeat and get a win 10 license and flatten it.

[Rhodesy]

Just to follow this up. I tried and failed again today to render a couple of scenes on the windows 8 machine so I installed windows 10 and its rendering the first one with no problems right now. Just FYI anyone else in the same boat - ditch windows 8 ASAP!

[Nejc Kilar]

This is really interesting. Thanks for posting about it Rhodesy.

[fellazb]

Is your W8 a home edition perhaps? Asking because a home edition on W8 probably only utilizes 16 Gb even even you installed more, this was the case with my W7 home edition. A pro version doesn't have this issue. When I updated to W10 the problem was gone since W10 uses all RAM regardless updating from a w7 home edition.