Hi Sebastian, > Von: Sebastian Andrzej Siewior [mailto:bigeasy@xxxxxxxxxxxxx] > Gesendet: Donnerstag, 25. Februar 2016 17:29 > An: Wirth, Martin > Cc: linux-rt-users@xxxxxxxxxxxxxxx > Betreff: Re: AW: Large latencies with 4.4.1-rt6 > > On 02/25/2016 05:08 PM, Martin.Wirth@xxxxxx wrote: > > Hi Sebastian > > Hi Martin, > > > I will have access to the machine for longer testing next Monday again. But > I remember that v4.4.1-rt5 showed the same long latencies. > > Will try v4.4-rt3 and v4.4-rt2 beginning of next week. > > If this would be your first try I would suggest to run hwlatdetect in case BIOS > is calling for attention. However since you don't see this in > v4.1 is looks unlikely. It also might be help to have a log to see what the other > CPUs are doing around that time. Are they busy doing something or do they > pause as well. Also do try some fancy PM things (but then again why now > and not in v4.1 as well). > I tested a bunch of kernels today and the outcome is: 4.4.0-rt2: good 4.4.0-rt3: good 4.4.1-rt4: good 4.4.1-rt5: bad 4.4.1-rt6: bad 4.4.2-rt7: bad 4.4.3-rt9: bad 4.4.3-rt9 with commit b3b36ee61c780407737a321007a24cfe9c3668a7 reverted: good (good means max cyclictest latencies < 25 µs, bad means latencies > 500 µs) I'm not a kernel developer, so I have not the slightest clue if the revert makes sense or only is plastering over the real problem. Best wishes, Martin ��.n��������+%������w��{.n�����{�����ǫ���ܨ}���Ơz�j:+v�����w����ޙ��&�)ߡ�a����z�ޗ���ݢj��w�f
