Poor graphics subsystem performance

#16292,16125,13697 closed bug (duplicate)

Poor graphics subsystem performance

User:
“I experience bad performance of videocard (Haiku treats it as Radeon HD 5450 Cedar). Speed of some graphical operations (for exampe, selecting of an item in any menu) is extremely low. Haiku3D demo runs more slowly than even in my old low performance laptop. GLTeapot runs with hundrets FPS though. Lowering of resolution doesn’t help. Also I have 2 monitors if it is important.”

Waddlesplash:
“In that case, please try blacklisting the “cpuidle” kernel add-on.”

User:
“Yes, with blacklisted “cpuidle” it finally works. Thank you!”

Question:
I would really like to know what happened here, and if other user could profit from this investigation too. If someone is using a Radeon HD card, would disable the cpuidle add-on speed up the system or whatever in this case too?

No. The CPUidle problem affects a few other machines irrespective of graphics card (some with Intel ones are also affected.)

Why cpuidle is needed? Isn’t CPU HLT instruction enough?

HLT is only for interrupts; MONITOR/MWAIT (what the CPUidle module uses) are much more powerful than that. I do not know a lot about the various uses of these though.