You might get some network traces for comparison between the two servers, and look to see if synchronous operations are happening in the same places. You can also look at "service response times" in Wireshark to narrow down where things are taking longer.
On Wed, May 13, 2026 at 7:39 AM Lionel Cons <[email protected]> wrote: > > On Wed, 13 May 2026 at 00:12, Dan McDonald <[email protected]> wrote: > > > > On May 12, 2026, at 4:44 PM, Lionel Cons <[email protected]> wrote: > > > > > > On Tue, 12 May 2026 at 19:43, Dan McDonald <[email protected]> wrote: > > >> > > >> On May 12, 2026, at 5:48 AM, Lionel Cons <[email protected]> > > >> wrote: > > >>> > > >>> Are there suggestions on how to DRASTICALLY reduce Illumos nfsd I/O > > >>> latency on ZFS? > > >> > > >> You're using a slog device on your pool, right? > > > > > > No, but I can try. Can slog devices be used for the root pool? Also, > > > can slog devices be added and removes dynamically? > > > > Yes, and yes, respectively. HIGHLY recommend the lowest-latency device you > > can get your hands on for a slog. Think "small but fast NVMe drive." > > Is there anything which can be done on the network and scheduler side? > > Linux has realtime scheduler classes, could this be done for the nfsd > threads on Illumus too? Are there TCP6/IPv6 tuning parameters for > improved latency? > > Lionel > > ------------------------------------------ > illumos: illumos-zfs > Permalink: > https://illumos.topicbox.com/groups/zfs/T7c22b249653e43fb-Medd16ba86e5748e987f2e9be > Delivery options: https://illumos.topicbox.com/groups/zfs/subscription ------------------------------------------ illumos: illumos-discuss Permalink: https://illumos.topicbox.com/groups/discuss/T7c22b249653e43fb-M0fcc59454689c99bc151adb7 Delivery options: https://illumos.topicbox.com/groups/discuss/subscription
