Date: Sun, 15 Apr 2018 21:27:48 +0700 From: Eugene Grosbein <eugen@grosbein.net> To: "Rodney W. Grimes" <freebsd-rwg@pdx.rh.CN85.dnsmgr.net> Cc: Rick Macklem <rmacklem@uoguelph.ca>, Niels Kobschaetzki <niels@kobschaetzki.net>, "freebsd-net@freebsd.org" <freebsd-net@freebsd.org> Subject: Re: High rate of NFS cache misses after upgrading from 10.3-prerelease to 11.1-release Message-ID: <5AD36164.4000406@grosbein.net> In-Reply-To: <201804151419.w3FEJVi4046362@pdx.rh.CN85.dnsmgr.net> References: <201804151419.w3FEJVi4046362@pdx.rh.CN85.dnsmgr.net>
next in thread | previous in thread | raw e-mail | index | archive | help
15.04.2018 21:19, Rodney W. Grimes wrote: >>>> 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. >> >> Though one should remember that some important system utilities >> may and probably will not work with newer kernel, like /sbin/ipfw, route, >> ifconfig, netstat etc. > > I thought that as long as the newer kernel has the right > COMPAT_FREEBSD10 compiled in that all this stuff should work. > Am I miss understanding this kernel option? COMPAT_FREEBSD10 does not cover all cases (in-kernel structures etc.) and bugs can happen, too. You won't be happy if you discover similar case in /sbin/ipfw or ifconfig as this combination (old ipfw+new kernel) is not something we test thoroughly.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?5AD36164.4000406>