High CPU usage at upper frequencies


Sam - W7SSS - Bellevue WA
 

I’m running v1784.  It’s been real stable except when I tune to around 1545mhz to 1680mhz.  I note my performance graph shows cpu useage go to 100%.  I figure it needs more cpu bandwidth to handle the higher frequency.  But when I hit the stop button, sdr# quits responding.  I have to kill the process.

I’ll remove some unneeded processes in windows.


Edward MacDonald
 

Try removing plugins and then readd them one by one. Perhaps it is a plugin causing the problem ?


On Tue., Dec. 29, 2020, 12:50 a.m. Sam Sayers, KC7BYY, <sam_sayers@...> wrote:
I’m running v1784.  It’s been real stable except when I tune to around 1545mhz to 1680mhz.  I note my performance graph shows cpu useage go to 100%.  I figure it needs more cpu bandwidth to handle the higher frequency.  But when I hit the stop button, sdr# quits responding.  I have to kill the process.

I’ll remove some unneeded processes in windows.


jdow
 

Higher frequencies won't affect the CPU requirements for SDRSharp. It may require more, depending on the source type, in the glue DLLs involved; but, I highly doubt that. What is your source? Is it an rtlsdr dongle? Is it an E4000 tuner or R820T tuner? You might be up outside the tuning range of the dongle, if it is an E4000 dongle.

{^_^}

On 20201228 20:57:34, Sam Sayers, KC7BYY wrote:
I’m running v1784.  It’s been real stable except when I tune to around 1545mhz to 1680mhz.  I note my performance graph shows cpu useage go to 100%.  I figure it needs more cpu bandwidth to handle the higher frequency.  But when I hit the stop button, sdr# quits responding.  I have to kill the process.

I’ll remove some unneeded processes in windows.


Sam - W7SSS - Bellevue WA
 

I've removed most plugins.  I had to remove the plugin manager as it caused my cpu to run at 100% constantly.

I'm using a rtl-sdr v3 blog.  Try intentionally driving your cpu higher by running some other process first at low frequency then up above 1.5ghz.

I'll keep testing here.

Thanks for everyone's feedback.


jdow
 

You do not understand. SDRSharp processes rtlsdr dongles at the dongle sample rate not at the tuned frequency. The dongle output is at the IF frequency. And if the dongle was wide open 1.5 Gsps then even if you were tuned to 10 kHz the SDR would still be processing at 1.5 Gsps, with no difference in CPU load. If there is an SDRSharp related problem above 1.5 GHz, rather than a dongle failing to lock it's downconverter PLL, then it is something in the GUI. Run it barefoot absolutely no foreign plugins such as you get with the community edition and see if the problem persists. If a problem exists in the processing chain I'd be astonished.

You could also try SDRConsole to see if it shows the same effect with the same dongle.

As far as trying to load the system more - not on this system. It's an over powered monster that I've used for real time HD video processing. It is happy running three rtlsdr dongles, each at 2.4 ksps, two virtual machines, email, browsing, and youtube videos all without breaking a sweat. I find myself lately running a fourth rtlsdr dongle or an airspy HF+ on my "better than sudoku for keeping my mind working" personal SDR project. (I can still learn at over 3/4. It feels good.) Seriously, overloading this machine is not in the cards for a mere SDRSharp SDR. (I can overload the computer's GUI video chain with multiple SDRConsoles and a LOT RX windows in the matrix.)

{^_^}

On 20201229 13:45:01, Sam Sayers, KC7BYY wrote:
I've removed most plugins.  I had to remove the plugin manager as it caused my cpu to run at 100% constantly.

I'm using a rtl-sdr v3 blog.  Try intentionally driving your cpu higher by running some other process first at low frequency then up above 1.5ghz.

I'll keep testing here.

Thanks for everyone's feedback.


Sam - W7SSS - Bellevue WA
 

Well.  Forget anything with cpu usage.  From a cold boot sdr# now locks up shortly after the GUI loads.  It’s been running fine for at least the last two weeks.  I start and stop it several times a day.  The lockup suddenly started last night after tuning to 1545mhz.  Maybe that matters, maybe not.  This now leads lockup on start up.

i haven’t changed any configuration.  Real strange.


jdow
 

FWIW if anything the CPU usage is down a little at GHz frequencies. It's hard to tell at the 2% to 5% range.

{^_^}

On 20201229 13:45:01, Sam Sayers, KC7BYY wrote:
I've removed most plugins.  I had to remove the plugin manager as it caused my cpu to run at 100% constantly.

I'm using a rtl-sdr v3 blog.  Try intentionally driving your cpu higher by running some other process first at low frequency then up above 1.5ghz.

I'll keep testing here.

Thanks for everyone's feedback.


jdow
 

There is a historical reason, involving Open Sores extremists and a LOT of hard feelings, for rtlsdr support in SDRSharp being frozen in the dark ages. You can only nuke SDRSharp if you want a reliable stop. It will seldom restart after pressing the stop button. Part of the problem is with libusb in the picture you get to pick and choose which bugs you want to support and work around. The one AirSpy supports causes the rtlsdr lockups.

{^_^}

On 20201229 14:35:19, Sam Sayers, KC7BYY wrote:
Well.  Forget anything with cpu usage.  From a cold boot sdr# now locks up shortly after the GUI loads.  It’s been running fine for at least the last two weeks.  I start and stop it several times a day.  The lockup suddenly started last night after tuning to 1545mhz.  Maybe that matters, maybe not.  This now leads lockup on start up.

i haven’t changed any configuration.  Real strange.


Sam - W7SSS - Bellevue WA
 

In my 9 weeks of sdr experience, there is more than one thing I don’t know.  Lol.  I did go to electronic engineering college, learned rf and signal processing (1971-1974), but chose the computer field as it was booming.  I retired in ‘04 and I’m rusty.

sorry, I was trying to describe the symptom, and I knowingly applied a condition (cpu performance).

if you’re a ham, you’ll understand “thanks for being my Elmer”.


jdow
 

No problem - BSEE MSEE here in the 60s at a 4.5 year BS school that used to be very good but now I am currently very ashamed of. I embraced the dark side (software) in the late 70s after designing my own circuit analysis program "for grins and giggles." The results were surprisingly worth the effort so I did both RF and SW subsequently for awhile. Then did only SW. I started fiddling with SDRs a few years back and figured very quickly they are not emulating hardware. BUT, they still have to have most of the same functions involved in processing the signals. It's fun to learn at over 3/4. I hope you have fun learning, too.

Here is a page that's "interesting" as it shows the functions within the R820T chip. It's a basic superheterodyne receiver front end through IF output. The RealTek 2832 chip performs the sampling and USB interface. That's where the SDR mysteries begin in the signal chain. If you look up "CUTESDR" you can find Moe's write up on its design. It is "old tech"; but, it works. I'm using it to build my own undestanding of what is going on. It's all a deep dive; but, it's fun to have learned. (Learning is hell. Having learned is Heaven.)

{^_-}   <- lacks a critical piece of equipment to be an "Elmer". (And I wonder how many spit takes that punchline gets.)  Joanne

On 20201229 14:51:54, Sam Sayers, KC7BYY wrote:
In my 9 weeks of sdr experience, there is more than one thing I don’t know.  Lol.  I did go to electronic engineering college, learned rf and signal processing (1971-1974), but chose the computer field as it was booming.  I retired in ‘04 and I’m rusty.

sorry, I was trying to describe the symptom, and I knowingly applied a condition (cpu performance).

if you’re a ham, you’ll understand “thanks for being my Elmer”.


Sam - W7SSS - Bellevue WA
 

Having fun learning?  Oh YES.  It’s quite a learning path.

I have a concept I’d like to pass along to Airspy.  In short, I think someone should market a complete sdr kit with cables, antenna(s), feedline aimed at the educational market (13 to 18 year olds).  One package, one price for budgeting for schools or a gift.   A keep it simple approach.

Does anyone have teenagers that use an sdr?  

The idea uses a vertical market concept by offering and marketing to specific users.  Do you think Airspy’s hardware sales would increase?  I do.

I’m too old to start working again, so run with it if you wish.

comments?


Sam - W7SSS - Bellevue WA
 

Good news.  Fixed my mystery.  I ejected my sdr and powered it off.  Start sdr# and all is well.  During my cold boot yesterday, I got interrupted and forgot.  I think when I tuned high the sdr went into an oscillation.  Sdr# didn’t like the signal and would hang.

more good news is I’ve been using 1784 and it’s been great.  I’ll eventually look at more plugins.

I also decided my next sdr will be an Airspy R2 and Spyvector.


lee@eddystone.org
 

Consider yourself an Elmira, then, JD.

Lee


jdow
 

Elvira might be more fun. (I did a bit of costuming at one point....) Back then I could more or less get away with it. That's sadly no longer even close to the case.

{^_-}

On 20201230 20:15:48, lee@... wrote:
Consider yourself an Elmira, then, JD.

Lee






Pete Smith <n4zr@...>
 

Sam, can you elaborate?  I'm aware of ejecting thumb drives, but see no place where I can eject my Airspy HF+, which has stopped responding via USB.

73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now 
spotting RTTY activity worldwide. 
For spots, please use your favorite 
"retail" DX cluster.
On 12/30/2020 8:43 PM, Sam Sayers, KC7BYY wrote:

Good news.  Fixed my mystery.  I ejected my sdr and powered it off.  Start sdr# and all is well.  During my cold boot yesterday, I got interrupted and forgot.  I think when I tuned high the sdr went into an oscillation.  Sdr# didn’t like the signal and would hang.

more good news is I’ve been using 1784 and it’s been great.  I’ll eventually look at more plugins.

I also decided my next sdr will be an Airspy R2 and Spyvector.


jdow
 

I believe he has been running an rtlsdr dongle. Those things have a lockup mode that requires the dongle be powered down to reset it. Pulling it and putting it back in does that.

{^_^}

On 20201230 18:34:34, Pete Smith wrote:

Sam, can you elaborate?  I'm aware of ejecting thumb drives, but see no place where I can eject my Airspy HF+, which has stopped responding via USB.

73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now 
spotting RTTY activity worldwide. 
For spots, please use your favorite 
"retail" DX cluster.
On 12/30/2020 8:43 PM, Sam Sayers, KC7BYY wrote:
Good news.  Fixed my mystery.  I ejected my sdr and powered it off.  Start sdr# and all is well.  During my cold boot yesterday, I got interrupted and forgot.  I think when I tuned high the sdr went into an oscillation.  Sdr# didn’t like the signal and would hang.

more good news is I’ve been using 1784 and it’s been great.  I’ll eventually look at more plugins.

I also decided my next sdr will be an Airspy R2 and Spyvector.


Alan G4ZFQ
 

Pete,

I'm aware of ejecting thumb drives, but see no place where I can eject my Airspy HF+, which has stopped responding via USB.
On W10 it is in the normal place.
Can't say I've ever bothered, no data to lose.

73 Alan G4ZFQ


jdow
 

On 20201231 00:41:18, Alan G4ZFQ wrote:
Pete,

I'm aware of ejecting thumb drives, but see no place where I can eject my Airspy HF+, which has stopped responding via USB.

On W10 it is in the normal place.
Can't say I've ever bothered, no data to lose.

73 Alan G4ZFQ
I wonder what he was doing before it quit responding. That may be VERY important to know.

{^_^}


Pete Smith <n4zr@...>
 

OK.  I use my HF+ for the Spectrum Display in N1MM Logger+.  When the display is not in use, the HF+ simply sits in the loop between RX Ant out and RX  Ant in on my K3 Transceiver.  It is not exposed to RF unless I activate that loop.  The HF+ has always been cranky about starting in response to spyserver, but has always started sooner or later - not this time, and the Device Manager displays that 43 error, telling me that USB communication has failed.  I've done all the usual trouble-shooting steps and followed on-line advice for clearing the 43 error, all to no avail.  Still waiting for a reply from Airspy.us.

73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now 
spotting RTTY activity worldwide. 
For spots, please use your favorite 
"retail" DX cluster.
On 12/31/2020 4:18 AM, jdow wrote:

On 20201231 00:41:18, Alan G4ZFQ wrote:
Pete,

I'm aware of ejecting thumb drives, but see no place where I can eject my Airspy HF+, which has stopped responding via USB.

On W10 it is in the normal place.
Can't say I've ever bothered, no data to lose.

73 Alan G4ZFQ
I wonder what he was doing before it quit responding. That may be VERY important to know.

{^_^}


jdow
 

Don't abuse your cables so much. If you have not noticed those (damn) tiny connectors are very delicate. Have you tried a substitute cable?

{^_^}

On 20201231 06:56:38, Pete Smith wrote:

OK.  I use my HF+ for the Spectrum Display in N1MM Logger+.  When the display is not in use, the HF+ simply sits in the loop between RX Ant out and RX  Ant in on my K3 Transceiver.  It is not exposed to RF unless I activate that loop.  The HF+ has always been cranky about starting in response to spyserver, but has always started sooner or later - not this time, and the Device Manager displays that 43 error, telling me that USB communication has failed.  I've done all the usual trouble-shooting steps and followed on-line advice for clearing the 43 error, all to no avail.  Still waiting for a reply from Airspy.us.

73, Pete N4ZR
Check out the Reverse Beacon Network
at <http://reversebeacon.net>, now 
spotting RTTY activity worldwide. 
For spots, please use your favorite 
"retail" DX cluster.
On 12/31/2020 4:18 AM, jdow wrote:
On 20201231 00:41:18, Alan G4ZFQ wrote:
Pete,

I'm aware of ejecting thumb drives, but see no place where I can eject my Airspy HF+, which has stopped responding via USB.

On W10 it is in the normal place.
Can't say I've ever bothered, no data to lose.

73 Alan G4ZFQ
I wonder what he was doing before it quit responding. That may be VERY important to know.

{^_^}