Re: Xen based VPS / OpenBSD 6.2 / OpenVPN 2.4.4 => Slow download speed after upgrade

Hi again.









After fiddling with pf and trying to statistically determine the cause




of the problem I did another search on the net and found this thread
[1].



Here the author suggests:









"when this slow problem occurs, you must disable the checksum on the




physical and virtual cards and restart the xenserver."









Does anyone know what exactly is meant by that?









I then searched in the CVS log of xnf development [2] and found this




statement:









"Emulated em(4) or re(4) drivers will




take over if xnf(4) driver is disabled or not compiled in."









This gave me the idea to disable xnf in the kernel, for now just




temporarily upon boot, for example like this [3]:









----




boot> boot bsd -c




...




ukc> disable xnf




----









As a result the booted systems now finds the `vio`









=== Case 6: Client <= VPN = Server <= WAN (vio)




* From client download external file from WAN via VPN tunnel with Virtio
driver







* Testresult:









----




→ curl http://fra36-speedtest-1.tele2.net/100MB.zip > /dev/null




% Total % Received % Xferd Average Speed Time Time Time
Current



Dload Upload Total Spent Left
Speed



100 100M 100 100M 0 0 2226k 0 0:00:46 0:00:46 --:--:--
4041k



----














If I'm not mistaken this gives reason to believe that there is an issue




with the xnf driver. I will mostly likely contact the xnf developer
about



this. In the best case xnf can be fixed and the download performance be




improved.









Thank you all for your help and feedback.









Berry




____









[1] http://daemonforums.org/showthread.php?p=61158




[2] https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/sys/dev/pv/if_xnf.c




[3] https://man.openbsd.org/config