On Tue, 27 Oct 2020 00:36:23 +0100 Toke Høiland-Jørgensen <t...@redhat.com> wrote:
> The memlock rlimit is a notorious source of failure for BPF programs. Most > of the samples just set it to infinity, but a few used a lower limit. The > problem with unconditionally setting a lower limit is that this will also > override the limit if the system-wide setting is *higher* than the limit > being set, which can lead to failures on systems that lock a lot of memory, > but set 'ulimit -l' to unlimited before running a sample. > > One fix for this is to only conditionally set the limit if the current > limit is lower, but it is simpler to just unify all the samples and have > them all set the limit to infinity. > > Signed-off-by: Toke Høiland-Jørgensen <t...@redhat.com> This change basically disable the memlock rlimit system. And this disable method is becoming standard in more and more BPF programs. IMHO using the system-wide memlock rlimit doesn't make sense for BPF. I'm still ACKing the patch, as this seems the only way forward, to ignore and in-practice not use the memlock rlimit. Acked-by: Jesper Dangaard Brouer <bro...@redhat.com> I saw some patches on the list (from Facebook) with a new system for policy limiting memory usage per BPF program or was it mem-cgroup, but I don't think that was ever merged... I would really like to see something replace (and remove) this memlock rlimit dependency. Anyone knows what happened to that effort? -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer
