High DPC Latency Windows 8?

Telvana

Honorable
Sep 16, 2013
5
0
10,510
I get random stutters during playback in Spotify, and Foobar 2k. I've narrowed it down to a DPC latency issue, but I am not really sure where to start with this log. Here's my system specs.

ASRock Z77 Extreme 4
Intel Core i5 3570k
2x 320 GB WD Velociraptor RAID 0
ASUS Xonar Essence STX
Diamond HD 7970
16 GB Corsair Vengeance 1866

I've run Prime95, etc. The system is 100% stable @ 4.5 Ghz and 1866 MHz on the Memory.

Here's the log from LatencyMon ... maybe it's my network card causing the issues? The network is the onboard Broadcom Netlink Gigabit Ethernet. I checked for updates to the drivers, and couldn't find any.

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CONCLUSION
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Your system seems to have difficulty handling real-time audio and other tasks. You may experience drop outs, clicks or pops due to buffer underruns. One or more DPC routines that belong to a driver running in your system appear to be executing for too long. At least one detected problem appears to be network related. In case you are using a WLAN adapter, try disabling it to get better results. One problem may be related to power management, disable CPU throttling settings in Control Panel and BIOS setup. Check for BIOS updates.
LatencyMon has been analyzing your system for 0:54:27 (h:mm:ss) on all processors.


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SYSTEM INFORMATION
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Computer name: APOLLOAP
OS version: Windows 8 , 6.2, build: 9200 (x64)
Hardware: ASRock, Z77 Extreme4
CPU: GenuineIntel Intel(R) Core(TM) i5-3570K CPU @ 3.40GHz
Logical processors: 4
Processor groups: 1
RAM: 16334 MB total


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CPU SPEED
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Reported CPU speed: 3400.0 MHz
Measured CPU speed: 2874.0 MHz (approx.)

Note: reported execution times may be calculated based on a fixed reported CPU speed. Disable variable speed settings like Intel Speed Step and AMD Cool N Quiet in the BIOS setup for more accurate results.


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MEASURED INTERRUPT TO USER PROCESS LATENCIES
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The interrupt to process latency reflects the measured interval that a usermode process needed to respond to a hardware request from the moment the interrupt service routine started execution. This includes the scheduling and execution of a DPC routine, the signaling of an event and the waking up of a usermode thread from an idle wait state in response to that event.

Highest measured interrupt to process latency (µs): 577.952338
Average measured interrupt to process latency (µs): 4.412733

Highest measured interrupt to DPC latency (µs): 472.541542
Average measured interrupt to DPC latency (µs): 1.000340


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MEASURED SMI, IPI AND CPU STALLS
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The SMI, IPI and CPU stalls value represents the highest measured interval that a CPU did not respond while having its maskable interrupts disabled.

Highest measured SMI or CPU stall (µs) 17.769249


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REPORTED ISRs
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Interrupt service routines are routines installed by the OS and device drivers that execute in response to a hardware interrupt signal.

Highest ISR routine execution time (µs): 150.927059
Driver with highest ISR routine execution time: USBPORT.SYS - USB 1.1 & 2.0 Port Driver, Microsoft Corporation

Highest reported total ISR routine time (%): 0.002221
Driver with highest ISR total time: Wdf01000.sys - Kernel Mode Driver Framework Runtime, Microsoft Corporation

Total time spent in ISRs (%) 0.003826

ISR count (execution time <250 µs): 357393
ISR count (execution time 250-500 µs): 0
ISR count (execution time 500-999 µs): 0
ISR count (execution time 1000-1999 µs): 0
ISR count (execution time 2000-3999 µs): 0
ISR count (execution time >=4000 µs): 0


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REPORTED DPCs
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DPC routines are part of the interrupt servicing dispatch mechanism and disable the possibility for a process to utilize the CPU while it is interrupted until the DPC has finished execution.

Highest DPC routine execution time (µs): 1140.918235
Driver with highest DPC routine execution time: tcpip.sys - TCP/IP Driver, Microsoft Corporation

Highest reported total DPC routine time (%): 0.627116
Driver with highest DPC total execution time: cmudaxp.sys - C-Media Audio WDM Driver, C-Media Inc

Total time spent in DPCs (%) 1.138190

DPC count (execution time <250 µs): 30900075
DPC count (execution time 250-500 µs): 0
DPC count (execution time 500-999 µs): 61
DPC count (execution time 1000-1999 µs): 1
DPC count (execution time 2000-3999 µs): 0
DPC count (execution time >=4000 µs): 0


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REPORTED HARD PAGEFAULTS
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Hard pagefaults are events that get triggered by making use of virtual memory that is not resident in RAM but backed by a memory mapped file on disk. The process of resolving the hard pagefault requires reading in the memory from disk while the process is interrupted and blocked from execution.

NOTE: some processes were hit by hard pagefaults. If these were programs producing audio, they are likely to interrupt the audio stream resulting in dropouts, clicks and pops. Check the Processes tab to see which programs were hit.

Process with highest pagefault count: oodag.exe

Total number of hard pagefaults 10783
Hard pagefault count of hardest hit process: 2804
Highest hard pagefault resolution time (µs): 4422067.335882
Total time spent in hard pagefaults (%): 1.042458
Number of processes hit: 39


_________________________________________________________________________________________________________
PER CPU DATA
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CPU 0 Interrupt cycle time (s): 166.803875
CPU 0 ISR highest execution time (µs): 150.927059
CPU 0 ISR total execution time (s): 0.499930
CPU 0 ISR count: 357393
CPU 0 DPC highest execution time (µs): 309.465294
CPU 0 DPC total execution time (s): 53.785571
CPU 0 DPC count: 17875215
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CPU 1 Interrupt cycle time (s): 77.909743
CPU 1 ISR highest execution time (µs): 0.0
CPU 1 ISR total execution time (s): 0.0
CPU 1 ISR count: 0
CPU 1 DPC highest execution time (µs): 276.040294
CPU 1 DPC total execution time (s): 30.827662
CPU 1 DPC count: 2109103
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CPU 2 Interrupt cycle time (s): 77.720225
CPU 2 ISR highest execution time (µs): 0.0
CPU 2 ISR total execution time (s): 0.0
CPU 2 ISR count: 0
CPU 2 DPC highest execution time (µs): 1140.918235
CPU 2 DPC total execution time (s): 31.828089
CPU 2 DPC count: 2924053
_________________________________________________________________________________________________________
CPU 3 Interrupt cycle time (s): 116.867791
CPU 3 ISR highest execution time (µs): 0.0
CPU 3 ISR total execution time (s): 0.0
CPU 3 ISR count: 0
CPU 3 DPC highest execution time (µs): 477.850588
CPU 3 DPC total execution time (s): 32.297978
CPU 3 DPC count: 7991766
_________________________________________________________________________________________________________

 
Solution
The ASUS sound card drivers are known for latency issues. Did you use the same card under another version of Windows with no problems? There are third party "UniXonar" drivers which are optimized for low latency.

http://maxedtech.com/category/uni-xonar/
The ASUS sound card drivers are known for latency issues. Did you use the same card under another version of Windows with no problems? There are third party "UniXonar" drivers which are optimized for low latency.

http://maxedtech.com/category/uni-xonar/
 
Solution

Telvana

Honorable
Sep 16, 2013
5
0
10,510
Yes, I used the ASUS drivers under Windows 7 without any real issues, at least I never noticed any. I'll try the UniXonar drivers and let you know if that solved it. I did notice that the drivers for the Sound Card were quite high up there in the latency also.
 


This is a result of the lazy bastards that are supposed to be writing audio codec drivers sleeping on the job. Creative Labs had this problem for years and in some configurations it was never solved.
 

Telvana

Honorable
Sep 16, 2013
5
0
10,510


UniXonar seems to have fixed the problem. Latency is down quite a bit, and no more stuttering. Thanks!