OpenRails performance on low end system

[conrail1]

Here are some results of running OpenRails on a 5 year old + machine.

The specs on this low end system (specs from CPUID below) –

ASUS P4C800-E (BIOS 1023)
Intel Pentium 4 (3.4GHz) w/Zalman CNPS7700-Cu
Mushkin PC3500 1024MB (2 x 512MB)
ATI X800XTX (Catalyst 10.2)
Creative Sound Blaster X-Fi Fatal1ty
WD 74GB Raptor - Windows XP/SP3
Enermax 600Watt PSU
CoolerMaster ATC-110



The hard drive was reformatted with a fresh XP/SP3 install along with the latest updates from Microsoft and the latest Catalyst drivers that support the X800 series cards which are the 10.2’s.

After spending a while on a compromise between image quality and performance I settled on 1920x1200 resolution, 6xAA/16xAF with “Adaptive Anti-Aliasing” set to “Performance” to try and get rid of the usual transparency texture simmering problem with ATI video cards (ATI CCC screens below). The “Quality” setting caused too much of a performance hit to usable but did get rid of most of the shimmering.

As you see from the screen shots performance was dismal and scenery loading caused so much stuttering that it made it hard to jump ahead of the train to take screen shots.

Not that I think the performance would have been better (it probably would have been worse) but I had originally set up this test with an Nvidia 5900 Ultra. With that card I couldn’t even get OR to load due to the “External component has thrown an exception” error issue.

Lowering the resolution to 1600x1200 and the AA to 4x also didn’t do much to help performance.

One thing that I found interesting with this setup is that the clouds in the sky would “skip” across the screen. I don’t know if this is an example of the OR game engine doing its job at reallocating resources away from some of the eye candy in order to run the simulation or not?



I had Hyper-threading enabled on the Pentium 4 so the F-5 info shows 2 processors.

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23 fps

[conrail1]

CPU-Z system info -

[conrail1]

ATI image quality settings -

[Train-a-Mania]

Again, that's assuming something with a 3.4 GHz processing speed is low-end. Your ram is low-end, but not the processor.

[twpol]

Have you tried with hyper-threading disabled? Does it make any difference?

[GaryG]

Hi

I'm thinking that with a hyperthreaded single core that ORTS may be accidentally causing some poor performance.

ORTS sees two processors so it thinks there is no problem with the background process running at full speed thus affecting the other process which doesn't get the CPU time needed and slowing everything down.

GaryG

[twpol]

I'm thinking that with a hyperthreaded single core that ORTS may be accidentally causing some poor performance.

Yeah, that's the same thought which occured to me. OR will split render and updater operations into separate threads when there is 2 or more logical cores, but in the case of a single physical core with hyper-threading it might not be the best idea to do that.

[conrail1]

Again, that's assuming something with a 3.4 GHz processing speed is low-end. Your ram is low-end, but not the processor.

Guys before we turn this into another flame war thread can we at least show a little common sense with the responses?

The Pentium 4 as far as running applications that hit system resources hard (recent sims/games) are concerned is low end, period.

The RAM (PC3500 with very tight timings) by the way would not be considered low end for this setup, the amount of RAM however would be.

[conrail1]

Have you tried with hyper-threading disabled? Does it make any difference?

I'm thinking that with a hyperthreaded single core that ORTS may be accidentally causing some poor performance.

ORTS sees two processors so it thinks there is no problem with the background process running at full speed thus affecting the other process which doesn't get the CPU time needed and slowing everything down.

James, GaryG,

I will give it a try with Hyper-threading turned off but if I remember correctly turning Hyper-threading on or off in BIOS requires a reformat with the Pentium 4.

This might also explain the “skipping” clouds that I experienced with this setup.

On another subject I will be testing OpenRails soon with Hyper-threading enabled on the i7 975X and 980X based systems.

I’ve also tested OR on Vista with the two “high end” setups and as expected they both performed pretty much identical to what I’ve seen with Windows 7, I’ll post some results.

[GaryG]

Hi

Perhaps this could be solved with a ORST configuration option that allows the user to specify whether or not ORTS can multithread.

I don't know how possible this would be to add but it would be easier than a possible reformat so the user could disable hyperthreading.

GaryG

[conrail1]

Hi

Perhaps this could be solved with a ORST configuration option that allows the user to specify whether or not ORTS can multithread.

I don't know how possible this would be to add but it would be easier than a possible reformat so the user could disable hyperthreading.

GaryG

Gary,

That might be a useful option in the future. I’ll try and do some more research on what is really required when turning Hyper-threading” on and off and how it effects the OS.

Just as an experiment I turned it off in BIOS without a fresh OS install and it made no difference at all as far as the stuttering and OR was concerned. Windows task manager did show only one processor but it made no impact on performance that could see.

Anyway I don’t really want to spend too much time testing with a system that I don’t think will ever cut the mustard in the future with OpenRails. I did however scrounge up some more memory for a total of 2GB for this setup. It’s PC2700 (mixing up memory with a dual channel chipset/motherboard isn’t very ideal) so it’s miss-matched with the other 1GB of PC3500 that’s in there now but I lowered the RAM speed from DDR400 to DDR320 in BIOS and it’s been stable so far. All four modules are from Mushkin with very similar timings. Hyper-threading was turned off in BIOS and I just did another fresh XP/SP3 install to see if there is any difference with OpenRails.

I’ll post some new results when I get OR reinstalled.

[twpol]

If hyper-threading is a problem we'll of course add an option - and try to auto-select the right thing too. It sounds like disabling HT hasn't helped on conrail1's 5yo system, though.

[conrail1]

Turning off Hyper-threading in BIOS and adding 1GB of memory along with a fresh OS install didn’t seem to help the stuttering and over all very poor performance when running OR on this setup. It also did not cure the “skipping cloud” issue. The default routes in MSTS did perform a little better then the "Feather River Route", but comparing say the default “Marias Pass” route to the FR Route is almost as bad as comparing the graphics/detail in Crysis or Dirt2 to Pac-Man.

I did find out why I had recalled some mention of reformatting the OS when turning Hyper-threading off and on. It has to do with an issue where the Windows XP HAL (Hardware Abstraction Layer) would not recognize the system as being an “ACPI Multiprocessor PC” in the device manager after enabling Hyper-threading in BIOS. There are some other “workarounds” but the most consistent way to get remedy this problem was by reformatting the OS. It doesn’t seem to be an issue for Windows XP/SP3 (which includes a multi-core driver), Vista or Windows 7.

Anyway for what it’s worth I’ll put up some screens when I get a chance.

[conrail1]

Here are the results from turning Hyper-threading OFF along with adding an extra 1GB of RAM to the low end system.

The CPUZ information reflects the RAM increase –




As I mentioned earlier the RAM is a mix of 2x 512Mb (PC3500) and 2x 512Mb (PC2700). Since this motherboard uses the Intel 875P chipset a dual channel memory configuration is supported.

[conrail1]

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15 fps -