Re: freebsd 13 ryzen micro stutter

From: Santiago Martinez <sm_at_codenetworks.net>
Date: Sat, 27 Mar 2021 10:54:53 +0000
Hi, i have the same output as _at_Nils B. If i run with steal =2 and dtrace 
the micro stutter doesn't happen but as soon as i stop the dtrace script 
it the stutters come back again.

Santi

On 3/27/21 10:39 AM, Santiago Martinez wrote:
> Hi there, my pause are not that often ( with steal_thresh=2) , maybe 
> is around 30 secs or so.
>
> If i set the thresh to 1 or 0 they go away. Now im trying with =2 and 
> schedgraph.d.
>
> Santi
>
>
> On 3/25/21 10:04 AM, Alastair Hogge wrote:
>> On 2021-03-23 17:34, myfreeweb wrote:
>>> On March 23, 2021 9:11:46 AM UTC, Michael Gmelin <freebsd_at_grem.de> 
>>> wrote:
>>>>
>>>> On Mon, 22 Mar 2021 23:50:52 -0400
>>>> monochrome <monochrome_at_twcny.rr.com> wrote:
>>>>
>>>>> After about 8 months of struggling to narrow this down I did another
>>>>> search and saw this:
>>>>>
>>>>> https://www.reddit.com/r/freebsd/comments/lc8fwo/freebsd_13_vega_64_micro_stutter_in_x/ 
>>>>>
>>>>>
>>>>> I haven't seen this come up here so I thought I would bring it up.
>>>>>
>>>>> My story started sometime before around August last year when synergy
>>>>> started getting really annoying with stuttering. Pretty sure it
>>>>> wasn't like that when I first started tracking 13-current in around
>>>>> May 2020 (I was on 12 with scfb for a long time before that with no
>>>>> issues), but since then I have tried to eliminate as many variables
>>>>> as possible. First I switched to barrier instead of synergy. Shortly
>>>>> after that I realized it was happening all the time and not just a
>>>>> network problem, I started using foobillard to verify during tests. I
>>>>> tried different RAM combinations, different network cards, a variety
>>>>> of RAM timings, stripping rc.conf etc, powerd settings, also scfb,
>>>>> with no effect. It is observable with ping -f, a dot or two appears
>>>>> every time it glitches. It seemed much better with RC2, but now with
>>>>> RC3 it seems to be back with a vengeance, and since its my main
>>>>> workstation and barrier/synergy server host for several machines, it
>>>>> is unbearable to use. Both Win10 and devuan3 on the same machine are
>>>>> smooth with no issues. Any feedback or info would be appreciated.
>>>>>
>>>>> Hardware:
>>>>> ASRock B450M Pro4
>>>>> Ryzen 2400G, no OC
>>>>> 32M DDR4-2933
>>>>> Onboard Vega GPU, drm-fbsd13-kmod
>>>>> _______________________________________________
>>>> Without knowing much about the issue at hand, just a few ideas:
>>>>
>>>> Sysctls I would look at:
>>>> - raising *.cx_lowest
>>>> - different kern.eventtimer.timer
>>> None of these should be an issue, but:
>>>
>>> sysctl kern.sched.steal_thresh=1
>>>
>>> For some reason with the default value of 2, I'm seeing weird
>>> stuttering in youtube videos, games, etc. on a 5950X system. 1 (or 0,
>>> IIRC) works fine.
>> I have noticed this too, firefox exhibits the issue frequently, however
>> I have
>> found it most noticeable in games/dhewm3[0] or Yamagi Quake 2[1]. There
>> is a distinct pause every 3 or 4 seconds where the simulation advances
>> significantly. Thanks for the kern.sched.steal_thresh pointer that has
>> sorted
>> the issue out for now.
>>
>> $ dmesg | egrep '(CPU:|avail memory)'
>> CPU: AMD Ryzen 9 3950X 16-Core Processor (3500.02-MHz
>> K8-class CPU)
>> avail memory = 66779394048 (63685 MB)
>> With an AMD NAVI 8GiB GPU, the host should be able to play either game
>> well enuf,
>> Quake 2 came out in 1997 and Doom 3 2004. I am sure Quake 2 used to play
>> without issues on my old AMD bulldozer.
>>
>>
>> 0: https://www.freshports.org/games/dhewm3/
>> 1: https://github.com/yquake2/yquake2
>> _______________________________________________
>> freebsd-current_at_freebsd.org mailing list
>> https://lists.freebsd.org/mailman/listinfo/freebsd-current
>> To unsubscribe, send any mail to 
>> "freebsd-current-unsubscribe_at_freebsd.org"
Received on Sat Mar 27 2021 - 09:55:01 UTC

This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:41:27 UTC