====== Attendees ====== * cc@ * tuexen@ * jtl@ * rscheff@ * rrs@ * thj@ * peterlei ====== Ongoing Short Term Projects ====== * glebius@ asks whether it makes sense to improve the TCP timer precision. tuexen@ states that this is very useful for testing purposes. glebius@ will provide a patch to tuexen@ for testing and tuexen@ will provide feedback, if such a patch us useful for %%FreeBSD%% in general. This applies to the default stack only, not the the RACK or BBR stack, which uses HPTS for timers. Setting the ''%%sysctl%%'' variable ''%%kern.timecounter.alloweddeviation%%'' to zero allows the timers to run of very precisely, which is useful when running ''%%packetdrill%%''. However, it affects the overall system performance. * At least for testing purposes (packetdrill) it would be good to have LRO support for tun interfaces. tuexen@ suggested to generalize LRO to not depend on an Ethernet header being present. gallatin@ prefers to not make the LRO code more complex, since it most likely will impact the performance. tjh@ has [[https://reviews.freebsd.org/D37437|D37437]] under review, which allows the tun interface to add an Ethernet header. tuexen@ will test this to see if it can also be used to enable LRO for the tun interface. This seems netmap specific. tuexen@ will consider to use tap interfaces in packetdrill. * [[https://reviews.freebsd.org/D28822|D28822]] improves PRR. rrs@ and tuexen@ will review. Will be committed after stable/14 is branched. * BBLog is missing a man page. tuexen@ will write one. * tuexen@ will add tests for handling RST ACK segments in all states and test the base, RACK and BBR stack. * rscheff@ wants feedback for [[https://reviews.freebsd.org/D41715|D41715]], which is based on a patch from VMWare for CUBIC. cc@ will tested and reviewed and rscheff@ will integrate the feedback. * [[https://syzkaller.appspot.com/bug?extid=49e2532b9c11ffaa450f|Fatal trap NUM: page fault in in_pcbbind_setup]]: addressed in [[https://reviews.freebsd.org/D42084|D42084]]. glebius@ will look at it. ====== Ongoing Longer Term Projects ====== * Now the RACK and the BBR stack are compiled by default in head. rrs@ will remove the BBR stack, since it has several limitations. We discussed if the RACK stack could be made the default and what should drive this decision. tuexen@ will reach out to the mailing list to ask people to test the RACK stack and provide feedback. rrs@ will do some single stream performance testing and provide data to rscheff. In January, we will look again at the decision process based on the feedback we got. * It was discussed that it would be a good idea to move the freebsd stack from ticks to micro seconds. * rscheff@ is improving %%AccECN%% code: [[https://reviews.freebsd.org/D36303|D36303]]. rrs@ will review it and implement it for the rack stack. Also the interaction between LRO and %%AccECN%%++ has to be taken into account. * [[https://reviews.freebsd.org/D23230|D23230]] is implementing ECN++. rrs@ will review it. * tuexen@ wants to write a tool which dumps the BBLog information of a TCP endpoint from a life system or a core. Using ''%%kvm_read()%%'' has drawbacks as glebius@ pointed out, using a python kgdb script may be an alternative. An alternative is to write a python kgdb script which pumps data into ''%%tcplog_dumper%%''. This would allow to minimize code duplication. @glebius will try to work on this soon. ====== Next Meeting ====== 16 November 2023 @ 1500 UTC using [[https://meet.freebsd.org/group/public/FreeBSDTCPCall|FreeBSDTCPCall]]