FAQ Concerning Q29 "Celestia uses 100% of the CPU

[dave1235]

Concerning the FAQ

Q29:
Why does Celestia always use 100% of the CPU?
How can I make it use less?

A helpful tip to add might be to point out that when you go to Bookmarks and then to Organize Bookmarks, the program goes into freeze mode. Otherwise it continues to use the CPU heavily even though it is minimized and your using other programs. (My task manager system icon continues to read 100% CPU use and things run slow.)

At least thats the only way I found to stop it from running full tilt.
It would be great if Celestia 1.5 didn't call on the CPU so much when it wasn't the active program.

Below is my system info in case the problem is just me.

OS Name Microsoft Windows XP Home Edition
Version 5.1.2600 Service Pack 2 Build 2600
OS Manufacturer Microsoft Corporation
System Name LOIS-LAPTOP
System Manufacturer TOSHIBA
System Model Satellite M40X
System Type X86-based PC
Processor x86 Family 6 Model 13 Stepping 8 GenuineIntel ~1496 Mhz
BIOS Version/Date TOSHIBA V1.60, 09/06/2005
SMBIOS Version 2.34
Windows Directory C:\WINDOWS
System Directory C:\WINDOWS\system32
Boot Device \Device\HarddiskVolume1
Locale United States
Hardware Abstraction Layer Version = "5.1.2600.2562 (xpsp.040919-1030)"
User Name LOIS-LAPTOP\Lois
Time Zone Eastern Daylight Time
Total Physical Memory 512.00 MB
Available Physical Memory 45.88 MB
Total Virtual Memory 2.00 GB
Available Virtual Memory 1.96 GB
Page File Space 3.39 GB
Page File C:\pagefile.sys

Thanks for your time

David

[selden]

David,

Which version of Celestia are you using?
My copy of v1.4.1 for Windows uses 0 CPU when it's minimized (click on its _ button).

It also uses 0 CPU when any of the popup menu windows is active, not just the Organize Bookmarks menu.

[dave1235]

I'm using v1.4.1

I'm not going to worry about it and just see what happens with v1.5. If it still happens I'll let you guys know. ( On the other hand if you thinks its important to understand.. ask away. I've go some computer background so your instructions can be semi technical.) (Although I'm not sure want you meant by " (click on its _ button)" I assumed it was a way to find the version #)


David

Thanks for your time spent on Celestia.

[selden]

Sorry, I was referring to Windows' standard icon for minimizing a program's window. It's the icon in the upper right corner of the window which contains an underscore as its label. When I click that Icon of Celestia's window on my Windows XP Pro system, Celestia's window is minimized (no longer visible at all, actually) and Celestia no longer uses any CPU time.

[Johaen]

Sorry, I was referring to Windows' standard icon for minimizing a program's window. It's the icon in the upper right corner of the window which contains an underscore as its label. When I click that Icon of Celestia's window on my Windows XP Pro system, Celestia's window is minimized (no longer visible at all, actually) and Celestia no longer uses any CPU time.

I've noticed that sometimes (but not always, and there doesn't seem to be a pattern) when I minimize Celestia, it only drops to 50% of my CPU, 100% of one of the cores. Doesn't really hinder my PC at all, but I just found it odd.

[dave1235]

Sorry, I was referring to Windows' standard icon for minimizing a program's window.

Great ! It worked !

Thats going to be a time saver. Thanks

Assuming this isn't specific to my PC...
I would have to class that as a bit of a bug.(Or maybe its a unavoidable product of the Window's operating system.)

There has to be others who this is happening to who don't even realize its happening given that most don't display the Task Manager CPU usage icon in the system tray.

Thanks again.

[selden]

Johean,

Celestia is single threaded: it should not use more than 100% of a single CPU, i.e. 50% of a dual-core system. It would be interesting to find out what it is doing that would cause the other CPU to be used.

Dave,

You're quite welcome.

Celestia uses 100% of the CPU if it can't finish calculating the contents of its window before the computer decides it's time to redraw the screen. It's not a bug. This is what is described in the FAQ.

[Johaen]

Johean,

Celestia is single threaded: it should not use more than 100% of a single CPU, i.e. 50% of a dual-core system. It would be interesting to find out what it is doing that would cause the other CPU to be used.

I agree. It would be interesting. It's kinda weird how it works, actually. Process of events:

1. Celestia minimized: 50% CPU Usage, 0% 1st core, 100% of 2nd core.

2. Maximize Celestia: for about 2 seconds total CPU usage is about 60%, CPU 1 is around 85%, CPU 2 is around 30%. After 2 seconds total CPU usage jumps to 95%, CPU 1 around 85%, CPU 2 at 100%.

3. Minimize Celestia: 50% CPU Usage, 0% 1st core, 100% of 2nd core.


I really wish I could give more details, but I can't seem to find any sort of pattern. I just restarted Celestia, and now maximized it's using about 75% total CPU usage, 80% 1st core, 70% 2nd core. Minimized it's using 0%. Then I changed my view a bit, and increased the visible magnitude so that more stars are in view. Now it's reflecting the behavior described above. Blah. I really wish I could find a pattern. Maybe someone else with a dual-core processor could give their input. All this is with 1.5.0pre2 w/o any add-ons, details of my PC are below.


Also, now that I think about it, I'm pretty sure it's always the 2nd CPU that shows the odd behavior. Maybe that has something to do with it.


As I said above, it's not really a huge bother for me. It doesn't slow down my PC at all. It's just something I've noticed.

[Adirondack]

There is a 50/50 consumption on my vista-machine:

Celestia maximized:
Core 1: 47-53%
Core 2: 46-51%

Celestia minimized:
Core 1: ~2%
Core 2: ~3%

Hardware:
Asus P5B dL
Intel Core2Duo E6600
EVGA GF8800GTS/640MB
Nvidia ForceWare 100.65
Windows Vista Ultimate
Celestia 1.5.0CVS


Adirondack

[Arnavion]

I don't have a dula core CPU, but my v1.4.1 uses 100% whether Celestia is minimized or not. Also, Celestia lags whenever I have the Task Manager running, but doesn't otherwise.