Hi Nadia, On Sun, Nov 03, 2024 at 11:26:36AM +0100, Nadia Pinaeva wrote: > I would like to provide some more context from the user point of view. > I am working on a tool that allows collecting network performance > metrics by using conntrack events. > Start time of a conntrack entry is used to evaluate seen_reply > latency, therefore the sooner it is timestamped, the better the > precision is. > In particular, when using this tool to compare the performance of the > same feature implemented using iptables/nftables/OVS it is crucial > to have the entry timestamped earlier to see any difference. > > I am not sure if current timestamping logic is used for anything, but > changing it would definitely help with my use case. > I am happy to provide more details, if you have any questions. The start time will be accurate. However, stop time will not be very accurate: the netlink message containing the SEEN_REPLY status flag can sit in the socket queue for some quite time until the userspace software has a chance to receive and parse it. @Florian: Would you explore instead to extend the nf_conntrack_ecache infrastructure to allow to provide timestamps for netlink events? This can be enabled via toggle. That would allow to have a more accurate delta between two events messages. Thanks.
