High rate of NFS cache misses after upgrading from 10.3-prerelease to 11.1-release

[Rick Macklem]

Niels Kobschaetzki wrote:
[stuff snipped]
>It is a website with quite some traffic handles by three webservers behind a pair >of loadbalancers.
>We see a loss of 20% in speed(TTFB reduced by 100ms; sounds not a lot but >Google et al doesn’t like it at all) after upgrading to 11.1 with a combined upgrade >to php7.1. On another server without NFS that upgrade improved performance >considerably (I was told ca 30% by the front end-dev)
One thing you could try is booting the 11.1 kernel on an 10.3 system. Newer
FreeBSD kernels should work with older userland.
This would tell you if it is kernel changes or userland changes that are causing
the higher miss rate.

Good luck with it, rick