On Wed, 22 Jan 2025 at 11:07, Cedric Blancher <cedric.blancher@xxxxxxxxx> wrote: > > Good morning! > > IMO it might be good to increase RPCSVC_MAXPAYLOAD to at least 8M, > giving the NFSv4.1 session mechanism some headroom for negotiation. > For over a decade the default value is 1M (1*1024*1024u), which IMO > causes problems with anything faster than 2500baseT. Chuck pointed out that the new /sys/kernel/debug/ subdir could be used to host "experimental" tunables. Plan: Add a /sys/kernel/debug/nfsd/RPCSVC_MAXPAYLOAD tunable file, RPCSVC_MAXPAYLOAD defaults to 4M, on connection start it copies the value of /sys/kernel/debug/nfsd/RPCSVC_MAXPAYLOAD into a private variable to make it unchangeable during connection lifetime, because Chuck is worried that svc_rqst::rq_pages might blow up in our face. Would that be a plan? Ced -- Cedric Blancher <cedric.blancher@xxxxxxxxx> [https://plus.google.com/u/0/+CedricBlancher/] Institute Pasteur
