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Systemwide ping spikes and bandwith loss while using Firefox

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  • Last reply by Tobi

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Recently (a week ago? Could be longer and i didnt notice it) the whole system lags and with it comes a bandwith collapse in regular patterns (roughly every 5 seconds) while firefox is open. As the picture are showing, its only while using Firefox. Neither Edge nor Opera has this.

First picture is Nperf speedtest using Firefox. Second one is same test using MS Edge. Last is CMD ping to my router while FF was open.

I already started FF without addons, refreshed it, and also fully uninstalled (including the appdata folders) and reinstalled it, but its still happening.

Recently (a week ago? Could be longer and i didnt notice it) the whole system lags and with it comes a bandwith collapse in regular patterns (roughly every 5 seconds) while firefox is open. As the picture are showing, its only while using Firefox. Neither Edge nor Opera has this. First picture is Nperf speedtest using Firefox. Second one is same test using MS Edge. Last is CMD ping to my router while FF was open. I already started FF without addons, refreshed it, and also fully uninstalled (including the appdata folders) and reinstalled it, but its still happening.
Attached screenshots

Modified by Tobi

All Replies (2)

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Hi Tobi,

I'm sorry to hear you're having issues with latency issues. Did you check to see if you have anything running in your Windows Task Manager that looks suspicious? You can also check Firefox Task Manager to check out extensions and tabs that may be slowing down your Firefox.

You might want to do some scans for malware protection, preferably in Windows Safe Mode and without the internet connection if possible. Troubleshoot Firefox issues caused by malware Quick fixes if your Firefox slows down

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WMagicModel said

Hi Tobi, I'm sorry to hear you're having issues with latency issues. Did you check to see if you have anything running in your Windows Task Manager that looks suspicious? You can also check Firefox Task Manager to check out extensions and tabs that may be slowing down your Firefox. You might want to do some scans for malware protection, preferably in Windows Safe Mode and without the internet connection if possible. Troubleshoot Firefox issues caused by malware Quick fixes if your Firefox slows down

Thx for you answer.

I already did pretty much anything "standard" that is suggested on these sites. Including full scan with ESET, adware and scanned my network with wireshark/network monitor. As far as i can tell, there is nothing i should be suspicious of, and wireshark only shows that there is nothing coming trough during those spikes (multiple "TCP Fast retransmisions"; "TCP previous segment not captured" and "TCP Dup ACK"), which doesnt help me in finding the reason.

I also already disabled most of the "automatic connections" firefox does to no avail.