[Linuxptp-users] clockcheck jumps forwards and backwards

2017-04-04 Thread David Mirabito
Hello List, I understand PTP in general needs stable/symmetrical round-trip times to be at it's best and that things like non-PTP-aware switches will introduce noise. It makes sense that as the network gets less deterministic and symmetrical then PTP will necessarily perform worse - probably both

Re: [Linuxptp-users] clockcheck jumps forwards and backwards

2017-04-04 Thread Miroslav Lichvar
On Tue, Apr 04, 2017 at 06:52:21PM +1000, David Mirabito wrote: > Is it safe to assume, that given a crappy PTP network ptp4l would just > degrade to ntp-like performance at worst? Or are there some other > thresholds or sanity checks which would cause it to throw in the towel in > situations where

Re: [Linuxptp-users] clockcheck jumps forwards and backwards

2017-04-04 Thread Ian Thompson
Possibly following on from David’s post. We have a system with 18 boards in a rack, each board has a Altera SoC with the STM Ethernet MAC connected via gigabit Ethernet to an Arista ptp-aware switch and then a Spectracom GrandMaster. The boards are running Linux kernel 3.15.0. They lock quickly

Re: [Linuxptp-users] clockcheck jumps forwards and backwards

2017-04-04 Thread David Mirabito
Hi, The device is a: 00:14.0 Ethernet controller: Intel Corporation Ethernet Connection I354 (rev 03) Using bash-4.3# ethtool -i ma2 driver: igb version: 5.3.0-k firmware-version: 0.0.0 expansion-rom-version: bus-info: :00:14.1 supports-statistics: yes supports-test: yes s