CPU Usage Affects WiFi Speed?

[BenYap]

Was streaming (receiving/watching) a concert on Facebook Live and noticed a weird interaction between my CPU usage and network speed over WiFi. When I have the stream tab displayed, CPU usage ramped up to over 50% and my network speed immediately became highly unstable and cannot sustain a smooth stream. When the tab is in the background and I'm listening to the audio only it's perfectly fine. Actual network speed was consistently around 2Mbps when the tab is in background (the stream was stable on the screen at 2 Mbps shortly before the problem occurred) and oscillate between that and almost 0 (kbps range) when unstable. 

 

It seems to me that when CPU usage is high, around 50% or higher, the performance of the WiFi card is affected which is something strange to me. I mean CPU ramping up is fine, probably for the 720p video processing (I have a discrete Nvidia 940MX in my laptop) but affecting WiFi is weird, especially when it's only around 50% usage. 

 

I'm thinking if it's a software issue (Facebook or Windows or Chrome), interference, power draw issue or just a bad coincidence. I checked temperature, not a problem, they're all below 60 celcius. RAM usage is no where near saturated too, a few GBs left out of 8. My girlfriend faced the same issue on her laptop which is of totally different spec and we aren't even in the same place. So that probably rules out some hardware and router/service provider issue. 

 

CPU Usage and Wifi speed was measured using Windows' Task Manager while temp was read from AIDA 64. The processor is a i5 7200U and WiFi card is a Intel Wireless AC 3165. 

 

Just wondering if anyone faced similar issues or any tech experts out there. 

[Meag]

1 minute ago, BenYap said:

Was streaming (receiving/watching) a concert on Facebook Live and noticed a weird interaction between my CPU usage and network speed over WiFi. When I have the stream tab displayed, CPU usage ramped up to over 50% and my network speed immediately became highly unstable and cannot sustain a smooth stream. When the tab is in the background and I'm listening to the audio only it's perfectly fine. Actual network speed was consistently around 2Mbps when the tab is in background (the stream was stable on the screen at 2 Mbps shortly before the problem occurred) and oscillate between that and almost 0 (kbps range) when unstable. 

 

It seems to me that when CPU usage is high, around 50% or higher, the performance of the WiFi card is affected which is something strange to me. I mean CPU ramping up is fine, probably for the 720p video processing (I have a discrete Nvidia 940MX in my laptop) but affecting WiFi is weird, especially when it's only around 50% usage. 

 

I'm thinking if it's a software issue (Facebook or Windows or Chrome), interference, power draw issue or just a bad coincidence. I checked temperature, not a problem, they're all below 60 celcius. RAM usage is no where near saturated too, a few GBs left out of 8. My girlfriend faced the same issue on her laptop which is of totally different spec and we aren't even in the same place. So that probably rules out some hardware and router/service provider issue. 

 

CPU Usage and Wifi speed was measured using Windows' Task Manager while temp was read from AIDA 64. The processor is a i5 7200U and WiFi card is a Intel Wireless AC 3165. 

 

Just wondering if anyone faced similar issues or any tech experts out there. 

Maybe try and replicate it using a synthetic load and a youtube video on a different browser, That way you can check if it is just a issue with either facebook or the browser. From what I've experienced facebooks video streaming is rather poor when compared to that of youtubes, so it might be that as you said.

[Skanky Sylveon]

Some lower end WiFi cards have the CPU perform some of their operations.  That might explain the drops in WiFi usability.

[DOWNEY]

42 minutes ago, ShadowArk said:

Maybe try and replicate it using a synthetic load and a youtube video on a different browser, That way you can check if it is just a issue with either facebook or the browser. From what I've experienced facebooks video streaming is rather poor when compared to that of youtubes, so it might be that as you said.

Why would you quote an OP that is right above yours..? 

[Meag]

18 minutes ago, DOWNEY said:

Why would you quote an OP that is right above yours..? 

Because why not  (Didnt really think about that)

[BenYap]

On 6/5/2017 at 5:01 AM, ShadowArk said:

Maybe try and replicate it using a synthetic load and a youtube video on a different browser, That way you can check if it is just a issue with either facebook or the browser. From what I've experienced facebooks video streaming is rather poor when compared to that of youtubes, so it might be that as you said.

I tried replicating it using AIDA64's stress test and a similar 720p Facebook Live but couldn't reproduce the problem though. I had a Fb stream, a 1080p YouTube video (Linus' $69 Gaming PC, haha) running simultaneously in Chrome, CPU stressed to 100%, but everything ran smoothly. 

On 6/5/2017 at 5:35 AM, Cinnabar Sonar said:

Some lower end WiFi cards have the CPU perform some of their operations.  That might explain the drops in WiFi usability.

It seems like that isn't the case, at least not with the Intel AC 3165 that I have. Streams were smooth even when CPU usage is artificially pushed to 100%. 

 

I am guessing that it is a problem with Facebook. There was like half a million people watching that concert (One Love Manchester), their servers probably were stretched. Which might explain the fluctuating internet speed measured, coz the bottleneck is the server, not my computer. 

 

But I am surprised with the much reduced CPU load when the streams are minimised in the background (~50% vs ~10% on an i5 7200U). I thought they require almost the same CPU resources and the GPU is responsible for the display.  

 

Thanks for all the suggestions anyway. Appreciate it!