Crap Speedtest but good after reboot

[rockyd]

Did a speedtest yesterday for the first time in a while, and got 50Mb/s on my 750Mb/s service. I repeated it a few times with different servers same 50Mb/s. Rebooted my router and it came good.
So my question is what would cause that to happen.

[pythonic]

Can't suggest any likely cause as my Gargoyle devices have never exhibited this sort of behaviour even when left running continuously for as long as 6 months, but actions you could take which might help diagnose a possible cause if/when it happens include:
- check system state for exhausted memory and/or unusually high load averages (i.e. greater than about 80% of the total number of CPU cores)
- check system log for error messages
- run top to check for unusual process activity