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Comment by tda

4 years ago

I noticed this too when I used steam to stream a game to my laptop over good wifi. Every minute it would stutter for a second. I set up iperf3 tests and noticed the wifi lag increasing every minute between my macbook and my server and between my windows desktop pc and my server (when connected over wifi). Of course no lag when using cables, so I reasoned it was wifi related, and had noting to do with my setup (I used different clients, and different AP's). I then took my macbook (only portable computer I had) it too a nearby coffee shop with good wifi and I could still measure lag spikes every minute. So then I was really puzzled, was there some rogue device interfering with wifi all over the neighborhood? Finally I found a suggestion to turn off location services (or whatever it is called), and the spikes disappeared. And I learnt that even when it is not used (not sure it the lid was closed) a macbook can cause significant interference to the wifi for all other nearby devices.

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tda

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tomxor  4 years ago

> And I learnt that even when it is not used (not sure it the lid was closed) a macbook can cause significant interference to the wifi for all other nearby devices.

My partner has an older MBP, I noticed this the last time she was forced to updated her OS a major version... the thing no longer sleeps when you tell it to or when you close the lid, it will stay connected to wifi and quite happily saturate the network downloading updates.

Only way to be sure is to power off the stupid thing.

  • code_duck  4 years ago

    My understanding is this is an issue with new features of all sorts of laptop/desktop devices.

    For example, https://news.ycombinator.com/item?id=28639952

    "Do not leave XPS laptop in any sleep/hibernate/standby mode when placed in a bag" because they stay connected to wifi and may attempt to run updates etc when the user is not expecting or prepared for that, as far as cooling.

    • tomxor  4 years ago

      I own an XPS, it runs Debian, it only installs updates when I tell it to.

      Even if I decided to use the untended upgrades package, it wouldn't do it when I sleep the computer... that would just be stupid.

      14 replies →

    • edb_123  4 years ago

      I have had this issue with Thinkpads as well. The solution was to make sure to unplug the AC power adapter before putting it to sleep and putting it in my bag. Else it would go to sleep thinking that it's still on AC power, and happily wake itself up to install updates while in my bag. If power was disconnected after putting it to sleep, it would not be able to know it was on battery power.

  • Abishek_Muthian  4 years ago

    Yesterday my home DNS weren't resolving and noticed on PiHole that there were >30,000 requests of *.in-addr.arpa (Reverse DNS Lookup) from the iPhone+iPad of the guest to whom I gave the WiFi access and was saturating the Pi's CPU. I re-enabled rate limiting on PiHole and blocked the request with a filter.

    A cursory search on the issue says Bonjour is the culprit, I'm forwarding DNS requests to my PiHole instances on my gateway and latest iOS doesn't seem to like it; I haven't faced such issue earlier and I have this setup for several years now.

  • chris37879  4 years ago

    For extra fun, if while it's sleeping it's connected to a Display Port or USB-C display, it'll wake it up everytime it wakes the wifi for its 'power naps'. Disabling them in System Prefs doesn't change this.

draebek  4 years ago

People doing game streaming might be interested in this bug in the moonlight-qt repo that discusses people having this same problem, including various fixes: https://github.com/moonlight-stream/moonlight-qt/issues/159

hoten  4 years ago

Wow, I guess this is also why my local steam streaming (well, I use Moonlight but same difference) started lagging out of nowhere. I first noticed it 2 days ago, but before that I clocked 30 hours no problem, so I guess this is a brand new problem.

Gonna try turning off all my Mac devices location services, thanks for the tip.

  • tda  4 years ago

    This was a few years ago on a 2015 MBP running Catalina or whatever came before that. My guess is the adaptive bandwidth algorithm acutely switches to a lower bandwidth due to the lag spike, and then slowly recovers in the ten seconds after. And then 50 seconds later it starts over again. I suspect if I could have manually set the streaming quality to a fixed value the lag spike would hardly not be noticable at all, but the constant switching of the stream quality is what actually caused chopiness. Same might be the case with the OP's zoom calls

867-5309  4 years ago

if you have the wherewithal to use iperf then why not wireshark too? it's probably actively sniffing surrounding wifi frames to feed back to its proprietary version of WiGLE.net under the guise of super helpful "location based services"