Strange CPU Usage Issue in PTLE 8

[ru2def]

I've recently upgraded to ProTools LE 8 (from 7.3) on a WinXP platform with an MBox2 interface. While I love the new capabilities, I'm seeing a very strange issue with CPU load that is making the system nearly unusable.

• When PT is the foreground application and running idle, CPU load is nominal.
• When PT is in the foreground and playing, CPU load is higher but still nominal.
• When PT is visible in the background and idle, CPU load jumps to 100% and stays there.
• When PT is minimized and idle, CPU load is nominal again, even when using the same other apps as before.

This happens in newly-created sessions and imported sessions. This happens with and without plugins and with and without ReWire apps. This has quickly become a huge impediment for using ReWire applications in a PT session since I can't switch to them and have PT in the background.

The entire system ran fine and smooth with 7.0 and 7.3 before this, same hardware and underlying system.

Has anyone else seen this problem or know of a solution for it? I've searched the forums here but only found a couple references to overcoming CPU throttling (which is not at play here as it's a desktop system) or to PT8 just being a new system and requiring more resources (which is also not at fault here as the program runs fine when in the foreground).

[cwsand]

Gonna need more info - start by posting a SANDRA report. Make sure you've done ALL the optimizations in the Troubleshooting Thread. You might just try uninstalling LE 8.0 and reinstalling it. Have you tried the update to 8.0.1?

[otobot]

This is a known problem!

DigiTechSupt will say it's fixed in 8.01. But the exact same problem you described above still exists for many many users. Me included.

The issue was bigger before the release of 8.0 cs3, meaning it didn't matter wheter PT is in the foreground or not.. the real CPU usage (as seen in Windows Task Manager) would always be much higher (around 100%) than that shown in PT's CPU meter.

Now after 8.0 cs3, the real CPU usage dropped down significantly compared to the initial release. But only if PT is the foreground app.

Like you say, this is still a big issue when working with rewired apps that need to be accessed for tweaking etc..

See these threads:

http://duc.digidesign.com/showthread.php?t=236239

http://duc.digidesign.com/showthread...ight=CPU+issue

[ru2def]

Already tried the 8.0.1 update and the cs1 update with no difference. Oddly, it doesn't display this behavior until I open or create a session -- the main menu has no problem sitting in the background. But if I close a session that was misbehaving, it also no longer acts like this.

[ru2def]

So a quick experiment has shown that if either the Mix or Edit windows are displayed in the background, then CPU goes to 100%. If they are open but minimized, then CPU stays near zero. Seems to be an odd bug in rendering, perhaps?

[otobot]

Yes, you're right about minimizing/maximizing of mix and edit windows. That had also been reported in the main thread pre 8.0 cs3 when the graphics issue still was present in PT when PT was the active foreground app window. That workaround can be used when working with other app windows (rewired etc..).