Thanks, David. That's the kind of thing that I'd like to be able to display...pictures telling 1000 words, etc.
Ultimately, we're talking about linux (CentOS 6/7) running on modern multi-core hardware vs similar specs under some existing VSAN clusters (ESX 6). As I mentioned, it's intended as a stratum2 setup with a pair of logical hosts in each of multiple locations, served both via an anycast VIP from each site for "good enough" clients (potentially many thousands of them) and via a DNS pool for true ntpd-based clients that support quorum. The latter will likely number in the high hundreds or low thousands. The pool and anycast setups are intended to allow horizontal scaling of the service as clients from more sites leverage it. There's little doubt that qualitatively, the hardware servers will give better results, but the folks that manage the OpEx want to be able to quantify the negative impact that being on VMs might introduce. i.e. is it worth taking on the incrementally more expensive cost of 20-some server chassis to get the performance/accuracy increase over a similar number of VMs. Do you mind sharing how you plotted the linked graphs? Dan Dan Geist dan(@)polter.net (33.942962,-84.312118) http://www.polter.net ----- Original Message ----- From: "David J Taylor" <[email protected]> To: [email protected] Sent: Tuesday, October 6, 2015 2:20:20 AM Subject: Re: [Pool] benchmarking performance of ntpd on a virtual platform. Greetings, all. I've been challenged to show some evidence that ntpd running on a VM (as a stratum 2 server in a company-internal pool) really does perform differently than on bare metal. Can anyone point me to any non-anecdotal scenarios or tests that might help demonstrate the performance/accuracy differences? One thought I had was to make a small cluster of several VM servers and several bare metal ones and add all of them to some clients and simply observe deltas in ntpq stats. Does anyone know of other good ways to get some "apples-to-apples" comparison data? Thanks Dan Dan Geist dan(@)polter.net ==================================================== Dan, For what it's worth: Windows-10 "bare metal" GPS/PPS synched: http://www.satsignal.eu/mrtg/kiruna_ntp_2.html Windows-XP running in a VM on the above hardware: http://www.satsignal.eu/mrtg/web-server_ntp-b.html I don't have a comparison for Linux, and you don't specify what OS you wish to use. What sort of accuracy do you need? Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: [email protected] _______________________________________________ pool mailing list [email protected] http://lists.ntp.org/listinfo/pool _______________________________________________ pool mailing list [email protected] http://lists.ntp.org/listinfo/pool
