Celestia Forums

Just a quick note to report that on MY limited system, 1.5 hardly runs at
all. My FPS drop to something like 5 per MINUTE. Don't know why this is
yet, but again I'm still using my old Gateway, 256MB RAM, Intel Celeron
system.

Keep this up and I'll have to forget about house payments and start spending
my income on the brand new PC...

Please don't take this the wrong way. I appreciate the new development on
my favorite program. It's just that I can't really use it running this slow.

Is there something else I can investigate to determine why the FPS have
dropped so radically from 1.4 to 1.5?

Thanks, Bob

Are you using any Virtual Textures?

They currently have serious performance problems in v1.5 due to the changes in how depth sorting is done.
Chris plans to address this problem but hasn't done so yet. (Right now he's concentrating on improving spacecraft trajectory support, including the use of SPICE kernels and JPL ephemerides and enhanced object orientation specifications.)

Bob,

After disabling any VTs, you might try turning off Clouds and let us know if that makes any difference for you.

Testing the Basic render path with just Microsoft's software OpenGL v1.1 (i.e. with hardware acceleration disabled, so it's not identical to your situation), v1.5 runs at half the fps on my system when clouds are enabled compared to when they are not. Part of the depth sorting code change involved how clouds are drawn. I don't see any performance difference with clouds on or off in v1.4.1.

selden wrote:Are you using any Virtual Textures?

They currently have serious performance problems in v1.5 due to the changes in how depth sorting is done.

No Virtual Textures, Selden. In fact, I have done NO modifications to the
1.5 installation. Simply renamed my current 1.4 installation so that I could
install 1.5, and after the installation I ran 1.5 just to see what would happen.

Hope this info helps. Will play with the various render options and let
you know what I get.

Take care, Bob

Bob,

Running as slowly as you see probably indicates that Celestia v1.5 is paging heavily. Is your disk "busy" light on?

Yet another thing to check: does the v1.5 distribution that you're using include any hires textures? There are quite a few in the CVS repository. They'd make Celestia a lot bigger and doubtless would cause it to page on your system. You might try renaming the hires folder to something else (like "nohires") so Celestia doesn't try to load them.

The CVS repository also has quite a few models that aren't included in the normal Windows distribution. You might check in the extras folder to see if they're included. Move them elsewhere if they are.

256MB RAM is pretty low anyway (lower than what we'd recommend for running XP) - it could well be that something in 1.5 is causing you to use virtual memory a lot more (which means it has to use the HDD more). You can try increasing the Virtual Memory and see what happens? (right click on My COmputer, go to Properties, then to the Advanced tab, and click the top (Performance) "Settings" button there. Then go to the "Advanced" tab and see how much virtual memory you're using.

I'm not using VTs on my system and didn't notice any speed decrease with 1.5, but then I have a lot more RAM than you . But really, I'm surprised that your computer has been handling Celestia at all so far - even if you got a basic new PC today you'd be blown away by the performance increase.

selden wrote:Bob,

Running as slowly as you see probably indicates that Celestia v1.5 is paging heavily. Is your disk "busy" light on?

Yet another thing to check: does the v1.5 distribution that you're using include any hires textures? There are quite a few in the CVS repository. They'd make Celestia a lot bigger and doubtless would cause it to page on your system. You might try renaming the hires folder to something else (like "nohires") so Celestia doesn't try to load them.

The CVS repository also has quite a few models that aren't included in the normal Windows distribution. You might check in the extras folder to see if they're included. Move them elsewhere if they are.

Selden,

No HIRES textures in the folder, no disk paging, no more extras than in
my 1.4 installation... The render values were set to display only

1. atmospheres
2. clouds
3. comet tails
4. night-side lights
5. planets, and
6. stars

Star style was "Fuzzy Points" and auto-magnitude was enabled. No
labels or marks were enabled.

I did check my task manager to see what gives and found that the
system was indeed over-committed. I had approximately 300 MB of
active programs running while Celestia was up so some kind of paging
had to be taking place.

i.e. - The "Commit Charge" value was far above the 256MB my system
has available to it, but I noticed none of the other things you mentioned.

Also, my system is using 768MB in the "Virtual Memory" setting, but I
have seen absolutely NO disk activity while running the program. <shrug>
Thanks for the tip Malenfant.

Methinks I simply need to move into the 21st century with a new PC and
- of course - a nice LARGE graphics card and all the RAM I can get.

Thanks very much for the help.