Be careful using Apple wireless diagnostic package, uses a lot of /var/tmp space on a small Macbook air 128ssd
Col > On 29 Oct 2020, at 17:24, colin johnston <col...@gt86car.org.uk> wrote: > > This does seem to be solved with the checksum disable below, or at least > pings down to sub 10ms on Mac book air with Catalina beta 10.15.6, why aim > performs far better I don’t know. I tried to introduce load after cksum > disable and it did not see ping spikes as before > > How do we now explain to Apple to fix ? > > Col > > >> On 29 Oct 2020, at 14:08, J. Hellenthal via NANOG <nanog@nanog.org> wrote: >> >> I believe I have seen the same thing with a Mid 2015 11,4 running catalina. >> Not diagnosing further because I could not find a reason for it fast enough >> and not sure if it really had an impact at the moment…. but could you try >> the following >> >> >> sudo sysctl net.link.generic.system.hwcksum_tx=0 >> sudo sysctl net.link.generic.system.hwcksum_rx=0 >> sudo ifconfig en0 -rxcsum >> >> >> in reverse … to restore the settings >> >> sudo sysctl net.link.generic.system.hwcksum_tx=1 >> sudo sysctl net.link.generic.system.hwcksum_rx=1 >> sudo ifconfig en0 rxcsum >> >> >> If you have some specific tests to run I would be willing to run them here >> on Big Sur with the same laptop but I have nothing now that runs Catalina >> >> >> Wireshark used to in Catalina rack up cksum errors a lot while these were >> all at their defaults. >> >> >> >>> On Oct 29, 2020, at 08:23, Mark Tinka <mark.ti...@seacom.com> wrote: >>> >>> >>> >>> On 10/29/20 15:04, Cory Sell wrote: >>> >>>> Might be worth disabling each AP to see if there's one out there having an >>>> issue playing nice with the MacBook. Also try different combinations of >>>> two APs working together. It's possible the MacBook is flip flopping >>>> because the power levels are fighting each other. >>> >>> Tested all that, as well as dropping Tx power levels on each of the AP's to >>> Low so that there isn't any power coming from any other AP (despite being >>> quite far, already). >>> >>> And to confirm, when the laptop locks into an AP, it doesn't try to join >>> another one. When in range, power is very good (between -37dB and -52dB). >>> When I walk away, that AP becomes too far (as bad as -80dB), but the next >>> one close by is far better (same good values as before) and laptop connects >>> and sticks to that. >>> >>> Again, only impacts Catalina. No other Apple device, or the Windows PC that >>> is on the same WLAN. >>> >>> >>>> Does the Mac have this issue at your local coffee shop or another >>>> establishment with Wi-Fi? You can try to rule out the AirPort card in the >>>> Mac itself. >>> >>> Never tried, I generally work from home. If I'm out, it's faster to tether >>> to my 4G service rather than any public wi-fi. >>> >>> Mark. >> >> >> -- >> >> J. Hellenthal >> >> The fact that there's a highway to Hell but only a stairway to Heaven says a >> lot about anticipated traffic volume. >> >> >> >> >> >> >
