The dist-upgrades have wiped out all the previous kernels, of course. The only one left on the machine at all was the 5.0 from 19.04, and that's no good either. :(
Linux 5.0.0-29-generic #31-Ubuntu SMP Thu Sep 12 13:05:32 UTC 2019 x86_64 Wed 23-Oct-19 04:47 sent 459,277,171 bytes received 35 bytes 5,635,303.14 bytes/sec The window is too large for me to bisect any time soon. The machine is inconveniently located for such things, but needs to stay there for the testing to be valid; and I don't expect to be able to average more than one build every few days. I'll do what I can to at least narrow things down a little, but since it took more than 6 months to get the last regression fixed after I'd already provided the exact release that introduced it, I'm sure you can understand why I'm not too keen on burning days of my free time on this. 4.15.0-55 is the last *recorded* good, but I did test 18.04 from a USB prior to installing that and hit 80+, so at least one version of 4.18 is okay. I'll re-check that build first just in case, then try a Live 18.04.3. If that one's good, the range would only be 5.0-xx to 5.0-29, and i can probably get that covered in a few weeks. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1847892 Title: large performance regression (~30-40%) in wifi with 19.10 / 5.3 kernel Status in linux package in Ubuntu: Confirmed Bug description: Probably relevant: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1795116 Card is an RTL8723BE. On 16.04 with the HWE stack, after 1795116 was fixed performance was a stable 75-80Mb/s. Linux 4.15.0-55-generic #60~16.04.2-Ubuntu SMP Thu Jul 4 09:03:09 UTC 2019 x86_64 Fri 26-Jul-19 12:28 sent 459,277,171 bytes received 35 bytes 9,278,327.39 bytes/sec Linux 4.15.0-55-generic #60~16.04.2-Ubuntu SMP Thu Jul 4 09:03:09 UTC 2019 x86_64 Sat 27-Jul-19 01:23 sent 459,277,171 bytes received 35 bytes 10,320,836.09 bytes/sec On 18.04, performance was still a stable 75-80Mb/s. After updating to 19.10, performance is typically ~50Mb/s, or about a 37% regression. $ iwconfig wlan0 wlan0 IEEE 802.11 ESSID:"**" Mode:Managed Frequency:2.442 GHz Access Point: 4C:60:DE:FB:A8:AB Bit Rate=150 Mb/s Tx-Power=20 dBm Retry short limit:7 RTS thr=2347 B Fragment thr:off Power Management:on Link Quality=59/70 Signal level=-51 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:0 Invalid misc:315 Missed beacon:0 $ ./wifibench.sh Linux 5.3.0-13-generic #14-Ubuntu SMP Tue Sep 24 02:46:08 UTC 2019 x86_64 Sat 12-Oct-19 20:30 sent 459,277,171 bytes received 35 bytes 5,566,996.44 bytes/sec $ iwconfig wlan0 wlan0 IEEE 802.11 ESSID:"**" Mode:Managed Frequency:2.442 GHz Access Point: 4C:60:DE:FB:A8:AB Bit Rate=150 Mb/s Tx-Power=20 dBm Retry short limit:7 RTS thr=2347 B Fragment thr:off Power Management:on Link Quality=68/70 Signal level=-42 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:0 Invalid misc:315 Missed beacon:0 So no corrupted packets or etc during that transfer. $ ifconfig wlan0 wlan0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.1.33 netmask 255.255.255.0 broadcast 192.168.1.255 ether dc:85:de:e4:17:a3 txqueuelen 1000 (Ethernet) RX packets 56608204 bytes 79066485957 (79.0 GB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 21634510 bytes 8726094217 (8.7 GB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 No issues of any kind in the week that it's been up. Just terrible performance. I'm painfully aware of all the module's parameters etc, and have tried them all, with no change in the results outside of typical wifi variance. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1847892/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
