High DPC Latency Issues with WPA

[WhiteG]

New to thread...and also to computer music servers. Thanks for great how-to", niemiro!

Ran LatencyMon on two scenarios...

1) Using USB2.0 cable on a USB3.0 PC port feeding a USB2.0 self-powered DAC. Do NOT get any YELLOW or RED bars but reported CONCLUSION is that "Your system seems to have difficulty handling real-time audio and other tasks...One problem may be related to power management. Disable CPU throttling settings in Control Panel and BIOS setup. Check for BIOS updates." INTERRUPTS TO USER PROCESS LATENCIES at 1,300 are approx 4 times what they were in scenario (2) below which were reported at approx. 350. Highest TOTAL EXECUTION (ms) was about 90,000 for <nusb3xhc.sys> but am running latest driver supplied by expansion card vendor. No idea how to deal with potential BIOS issues.

2) Using (same) USB2.0 cable on a USB2.0 port (without any other devices on the buss), bars are all GREEN and reported CONCLUSION is that "Your system appears to be suitable for handling real-time audio and other tasks without dropouts." Highest TOTAL EXECUTION (ms) was about 114,000 for <USBPORT.SYS> but all Microsoft updates are current.

Unclear why USB3.0 runs worse than USB2.0.

Thoughts?

 

[satrow]

Re: How to Diagnose and Fix High DPC Latency Issues with WPA (Windows Vista/7/8)

@ WhiteG: Welcome to Sysnative!

First thoughts would be poor USB 3 drivers, which motherboard and OS?

 

[WhiteG]

Re: How to Diagnose and Fix High DPC Latency Issues with WPA (Windows Vista/7/8)

@ WhiteG: Welcome to Sysnative!

First thoughts would be poor USB 3 drivers, which motherboard and OS?

Not sure how to ID the motherboard but PC is DELL OPTIPLEX 3010 with INTEL i5-3470 quad processor running Win7 (x64) Pro with Service Pack 1. Main circuit board is identified as "Dell Inc. 042P49 A01", if that helps.

DID have trouble initially with BSOD with StarTech PCIe SuperSpeed USB3.0 Card (Part# PEXUSB3S2) using original driver supplied but WAS provided with another driver by StarTech which seems to allow proper operation...but maybe not this application.

 

[satrow]

Re: How to Diagnose and Fix High DPC Latency Issues with WPA (Windows Vista/7/8)

So the USB 3 is via an add-in card not built into the 'board..

The StarTech brand is low-end from what I've seen, can you give details of the drivers as listed in the Properties sheet in Device Manager or a link to the model and the new drivers so we can look them over to find the chipset maker/version?

 

[WhiteG]

Re: How to Diagnose and Fix High DPC Latency Issues with WPA (Windows Vista/7/8)

So the USB 3 is via an add-in card not built into the 'board.. The StarTech brand is low-end from what I've seen, can you give details of the drivers as listed in the Properties sheet in Device Manager or a link to the model and the new drivers so we can look them over to find the chipset maker/version?

Yes, it was a expansion card for the original system from Dell. Link to StarTech item is as follows: <http://www.startech.com/Cards-Adapters/USB-3.0/Cards/2-Port-PCI-Express-SuperSpeed-USB-3-Card-Adapter~PEXUSB3S2> (DETAILED INFO BELOW)

Driver for USB3.0 Host Controller from Device Manager Properties is: Renesas Electronic Corporation, File Version 2.1.29.0 (nusb3drv 122611-0917)

[h=1]2 Port PCI Express SuperSpeed USB 3.0 Card Adapter[/h] PEXUSB3S2




Providing speeds up to 10x faster than that of USB 2.0, this PCI Express USB 3.0 card enables you to access your data and transfer files much faster than USB 2.0, by adding two USB 3.0 ports to your PCI Express capable PC.
Featuring a native NEC PCI Express host controller chipset, the new USB 3.0 standard supports transfer rates of up to 5Gbps, while still providing connectivity and support for the older USB 2.0 (480Mbps) and 1.1 (12Mbps) devices.
In addition to providing a much faster transfer rate the PEXUSB3S2 USB 3.0 card also supplies 900mA of power per USB port, allowing more and more external devices to operate without the need of an additional power source.

[h=5]The StarTech.com Advantage[/h]

• SuperSpeed USB 3.0 connectivity at up to 5 Gbps and 80% more power than USB 2.0
• Dual profile design to fit into Full or Low Profile/small form factor (SFF) systems
• Backed by a StarTech.com lifetime warranty and free lifetime technical support

[h=5]Features[/h]

• Provides two external USB 3.0 connections
• Fully compliant with USB 3.0 revision 1.0 specifications and Intel xHCI rev0.96 specifications, with transfer rates up to 5 Gbps
• Built-in optional LP4 Molex power connector for bus-powered USB devices
• Backwards compatible with USB 2.0 and USB 1.0/1.1 devices
• Optionally provides up to 900mA per USB port
• Compliant with PCI Express 2.0 specifications
• Supports up to 127 USB devices per port (requires additional USB hubs)
• Plug-and-Play and Hot-Swap compatible
• Support Control/Bulk/Interrupt/Isochronous USB Transfer modes
• Includes a Low Profile installation bracket

[h=5]Applications[/h]

• Upgrade an older PCIe-based system with USB 3.0 connectivity to fully utilize USB 3.0 devices
• Expand a system's USB capabilities with two additional external USB ports
• Connect additional external hard drives, CD/DVD drives, MP3 players, printers, scanners, webcams, game controllers, digital cameras, etc. to a computer system

[h=5]Product Numbers[/h]

Dell Harmony

A3337171

 

[WhiteG]

Re: How to Diagnose and Fix High DPC Latency Issues with WPA (Windows Vista/7/8)

ALSO, DRIVERS\nusb3xhc.sys File Version is 2.1.39.0 (nusb3drv.082112-1258). Sorry, should have included this as well.

 

[Digerati]

@WhiteG - Are you experiencing audio problems? I ask because I find that latency monitors like LatencyMon and DPC Latency Checker don't really, or consistently at least, reflect the real world. For example, on my machine, both checkers report I must be experiencing problems with dropouts, clicks, pops, and buffer overruns, but I suffer no such ill-effects - not while listening/viewing to streaming audio/video from Pandora (which I am doing right now), SiriusXM Internet Radio, YouTube or any other media sources, or while doing any tasks, for that matter.

Frankly, unless you are experiencing audio playback or other problems that truly are tied to latency issues, I would put as much stock in Latency Mon and DPC Latency Checker results as I do in WEI scores - which is not much, if any.

BTW, I have also noticed that some hardware monitors skew latency test results. Some users have reported EasyTune (the HW monitor and timing tweaker provided with Gigabyte motherboards), and the similar program from ASUS, have caused latency issues - at least as reported by the monitoring programs.

 

[WhiteG]

@WhiteG - Are you experiencing audio problems? I ask because I find that latency monitors like LatencyMon and DPC Latency Checker don't really, or consistently at least, reflect the real world. For example, on my machine, both checkers report I must be experiencing problems with dropouts, clicks, pops, and buffer overruns, but I suffer no such ill-effects - not while listening/viewing to streaming audio/video from Pandora (which I am doing right now), SiriusXM Internet Radio, YouTube or any other media sources, or while doing any tasks, for that matter.

Frankly, unless you are experiencing audio playback or other problems that truly are tied to latency issues, I would put as much stock in Latency Mon and DPC Latency Checker results as I do in WEI scores - which is not much, if any.

BTW, I have also noticed that some hardware monitors skew latency test results. Some users have reported EasyTune (the HW monitor and timing tweaker provided with Gigabyte motherboards), and the similar program from ASUS, have caused latency issues - at least as reported by the monitoring programs.

No dropouts, clicks, pops, or other obvious issues, Digerati, when I compare playback using the USB3.0 vs USB2.0 ports on the PC. It may be a case of reading some how-to's too literally and then having questions arise that my limited computer savvy cannot answer. So...forums like this can be very enlightening. I guess, "don't fix what ain't broke" , i.e., no Red or Yellow bars, may be applicable but the content of the CONCLUSION did pique my interest.

Maybe "satrow", etal., will find some issue with the USB3.0 expansion card driver, etc. Perhaps the StarTech card is itself the issue for an audio application. Fortunately I do NOT have a lot invested in this card and would not be put out if there were a better but less expensive alternative than the highly regarded $350 SOtM USB card. I just figured having the USB3.0 buss as a relatively isolated source of connectivity might be advantageous.

 

[Digerati]

I am not sure I would call a USB connection that is achieved via an expansion card "isolated" or ideal. Nor would I be that concerned with adding USB3.0 support to an existing system - mainly because USB3.0 is so new, and most USB devices are still 2.0.

But for sure, I am putting together a new computer for myself now and I made sure (1) my new motherboard supported USB3.0 natively and (2) my new case did too. And they both do, though I don't currently have any USB3.0 devices to connect to it.

Again, I think those programs may be helpful if you are experiencing problems, but if not, they can be confusing.

 

[Tekno Venus]

Hey there,

If I may add my own view on this matter...

I have been plagued with DPC Latency issues throughout the lifetime of this computer. In fact, the example problem image in the tutorial came from this exact system I am using now and have been using for the past year and a half:

When I took that screenshot, I was indeed suffering from clicks, pops, drop outs and laggy audio at regular intervals. I have since managed to reduce my latency issues a lot but there are still yellow and red bars appearing occasionally in DPC Latency checker. However, the audio issues have all but stopped and as a result, I have decided to leave it alone.

With this issue, I do believe the motto is "If it ain't broke, don't fix it!". The programs may be reporting errors, but if the PC is behaving itself, leave it alone. If you are experiencing real issues that are affecting your everyday usage, then we need to do something. If not, just let it lie IMHO.

Regards,
Stephen

 

[Digerati]

Wow, those "seem" pretty bad. I think it sad, if not a bit of a cop out they don't say which drivers "behave bad". And I have known of dozens of cases where folks followed those advice given, never with any results.

I would look at other things - like security software or hardware monitors - programs that set deep hooks and monitor hardware activity. As I noted above, some Gigabyte users fixed their problems by unloading EasyTune.

One person reported unplugging his mouse from his USB hub and connecting it directly to a motherboard USB port cleaned up his Latency issue (though he did not have any audio problems either).

 

[WhiteG]

Wow, those "seem" pretty bad. I think it sad, if not a bit of a cop out they don't say which drivers "behave bad". And I have known of dozens of cases where folks followed those advice given, never with any results.

I would look at other things - like security software or hardware monitors - programs that set deep hooks and monitor hardware activity. As I noted above, some Gigabyte users fixed their problems by unloading EasyTune.

One person reported unplugging his mouse from his USB hub and connecting it directly to a motherboard USB port cleaned up his Latency issue (though he did not have any audio problems either).

Thankfully, my system does not yield analysis charts like the one posted by Tekno Venus or provided in the Latency Checker tutorial, but am of the opinion that while potential issues may not impact audio in an obvious way, the impact may be subtle like those that might be evident with audio interconnects.

Tekno, not sure what OS you are running, but have you checked out any of the numerous how-to's on optimizing PCs for music application? To Digerati's point re security software, many of these guides recommend shutting down anti-malware software while the system is being used for music as well as disconnecting from the internet entirely, assuming you are not streaming audio and/or video. Also, if you are using USB for data transfer and depending on how many USB ports/busses you have, it may be worthwhile to "map" the ports so you know what devices are on which port and see if you can rearrange to free up a buss. I did this and then made my USB connection to this buss. (However, I am still curious what may be causing the report of potential issues with USB3.0 connectivity). Nothing audibly obvious but, IMHO, worth the effort. Many of the other tweaks including power management, etc., are mentioned in essentially every how-to that I have found.