The problem: Extremely annoying distortion/lag while playing games, in skype calls, in youtube video, and in movie playback with all video player apps (vlc, media player classic home cinema, windows media player).
The symptoms: 35-40% CPU usage (with respect to dual core) or 90% of one core, consumed by Interrupts and DPCs - easy to see in Microsoft's Sysinternals Process Explorer.
Operating system is: Windows 8.1 Update, with all the latest windows updates. No antivirus software running except for spybot search & destroy 2 free version, it's just a passive on-demand scanner that runs only when you request it to do a scan.
The hardware is: AMD E450 APU based Lenovo notebook, mid-2011. Came with windows 7 64 bit. Has AMD SB850 southbridge for sata hard drive, usb, network, sound.
Chipset, graphics, Ethernet, WiFi, USB drivers and BIOS, are up to date.
Steps taken to diagnose: I've run a trace with the Microsoft ADK (A s s essment and Deployment Kit) available here : http://www.microsoft.com/en-us/download/details.aspx?id=39982
( In case anyone needs the ADK commands, they are:
xperf -on latency -stackwalk profile -buffersize 1024 -MaxFile 256 -FileMode Circular && timeout -1 && xperf -d DPC_Interrupt.etl
Now, capture for 30 seconds when you face the latency issue. You can go back to command prompt and press any key to stop tracing. Now, run the following command to dump the data from the trace into a text file:
xperf -I DPC_Interrupt.etl -a dpcisr > dpc.txt
End of ADK trace commands. )
When you look at the DPC trace file, you see ADK logged 2.4 million interrupts to storport.sys in 24 million microseconds - that's 1 interrupt per 10 microseconds... that's crazy !
Excessive interrupt activity happening in storport.sys, amd_sata.sys, hdaudbus.sys.
Here's the DPC trace file http://1drv.ms/1i8SVas
Any help would be appreciated.
09:54 PM by