====== Attendees ====== * cc@ * olivier@ * rscheff@ * Peter Lei * rrs@ * thj@ * tuexen@ ====== 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. * [[https://reviews.freebsd.org/D39299|D39299]] improves compliance to [[https://www.rfc-editor.org/rfc/rfc6675|RFC 6675]] with regard to the ''%%isLost%%'' variable. rrs@ and cc@ will review it. cc@ tested in Emulab. 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://bugs.freebsd.org/bugzilla/show_bug.cgi?id=271677|PR 271677]]. No idea why this happens. * [[https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=274009|PR 274009]] and the following ''%%syzkaller%%'' issues are addressed by [[https://reviews.freebsd.org/D42031|D42031]]: * [[https://syzkaller.appspot.com/bug?extid=c8e3dac881bba85bc029|panic: in_pcblookup_hash_locked: invalid foreign address (2)]] * [[https://syzkaller.appspot.com/bug?extid=81ccc423a2737ed031ac|panic: in_pcblookup_hash_locked: invalid local address (2)]] The patch does not look elegant, but is consistent with the rest. * [[https://syzkaller.appspot.com/bug?extid=49e2532b9c11ffaa450f|Fatal trap NUM: page fault in in_pcbbind_setup]]: addressed in [[https://reviews.freebsd.org/D42084|D42084]]. This needs input from glebius@. * Why is ''%%net.inet.tcp.sack.enable%%'' a loader tunable? This question came up in [[https://reviews.freebsd.org/D41928|D41928]]. It should be changed to a ''%%sysctl%%''-variable. * Should [[https://cgit.FreeBSD.org/src/commit/?id=8818f0f1124ea3d0e8028f85d667237536eba10c|8818f0f1124e]] be MFCed to ''%%stable/14%%'' and ''%%releng/14.0%%''? Yes. tuexen@ will do it. ====== Ongoing Longer Term Projects ====== * It was discussed whether RACK and BBR can be build by default. RACK will be enabled in after stable/14 has been branched. tuexen@ discuss this with security@ and announc it on the net@ and current@ mailing lists. * 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. * [[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 ====== 05 October 2023 @ 1500 UTC