Re: udev being an ass
On Thursday 29 August 2019 21:34:33 Felix Miata wrote:
> David Wright composed on 2019-08-29 19:49 (UTC-0500):
> > Unfortunately, virtually every conversation about any of your
> > systems begins with a tirade about how Debian is completely broken,
> > whether it's the...
>
> I'm guessing most of it would be curtailed if he could install the
> current stable release of what has proven to be the most stable OS
> available and upgrade to a realtime kernel that controlled all his
> machine tools just like it used to be able to do before all the
> "improvements" got rolled into it.
>
I'd love it. Unforch, its often past a new distros sell by date by the
time someone gets around to patching an rtai version compatible with the
new kernels. Depending on the machine, acceptable performance can
sometimes be had with the much easier to build fully pre-emptible
kernel. We have found one of the stretch kernels is almost working, but
it has a habit of disconnecting from its own keyboard at random
intervals. Usually after a key down event but missing the key up that
would stop the jog. Unplugging the dongles will usually restore
operation after 2 or 3 reconnections. In the mean time the machine,
never having received the key up, is merrily moving a couple hundred
pounds of itself at up to 200 inches a minute until it runs out of room
and slams into the end of its travel, and $diety's help will be needed
for anyone unlucky enough to be in the way.
To be blunt, no way in hell will we install this
4.9.0-9-rt-amd64 #1 SMP PREEMPT RT Debian 4.9.168-1+deb9u5 (2019-08-11)
x86_64 GNU/Linux on a machine actually running a machine. I can
tolerate this as theres no real machinery tied to this box. So this is a
nuisance, not a potential maimer.
I have one buster installed, I'm very impressed, from raspian on a
raspberry pi 3b, which can use the newest buster build, something I
cannot get from debian because debian won't touch the new broadcom video
code and likely never will. Because the video in the latest raspian is
> 15x faster, its the only game in town to run on a pi.
We don't have that problem with amd64, and I expect we'll soon have a
good preempt-rt kernel for buster. But that won't fix my big lathe. So
I am building, installing and testing, working well except for the
snails pace video on what is basically a stretch install. All of which
takes time. Either a new kernel, or the latest linuxcnc is around a 4
hour build a deb job on the pi's. And AFAIK, no one is working on it
but me. I wanted to see, 2 years ago, If I could run big machinery from
a pi, I've done quite well, but I've also painted myself into a corner.
TBT, our coders spend more time chasing linux's changes that wreck our
stuff, than in making improvements to our code. It would be truly a
blessing if the changes to linux incrementally resulted in stable code
that barring security stuff, was long term stable. But it seems to be
getting worse, not better since wheezy.
My job, self appointed, is running the latest master code on all my
machines, serving as the canary in the coal mine, finding new bugs if I
can, so that the guys running the released code in a job shop making
5000 copies of something, don't get expensive surprises. You folks would
be surprised at the places you will find this code. Go into any car
parts place, and look at the high horsepower stuff. linuxcnc probably
carved 20% of the high performance crate engines you can only lease.
> Be kind. It ain't so much fun getting old, and the unfun is multiplied
> by being a caregiver for a spouse with dementia or strains simply to
> breathe even using an oxygen bottle or generator while limping along
> on a bunch of chemicals and replacement body parts to keep the old
> kicker kicking. Given his spouse's condition, this might be one of few
> opportunities he gets to communicate with people of intelligence. I'm
> sure he, like many in his age group, needs mental exercise as
> available here as much as he and others like him need physical
> exercise they don't get because of the existence of electronic video
> displays and all that appears on them for whatever reason.
>
> If you get old, and wise at the same time, you eventually figure out
> it's usually best to not fix what ain't broke, and highly annoying to
> have to fix what broke due to unavoidable purported software
> improvements that only got tested on hardware that's barely had the
> smell of new burned away.
Thanks for the flowers Felix, its actually a pretty good description. The
mental degradation as the years go by is the most maddening. To put that
into a long term perspective, I sat for Mensa 2 years ago, and failed.
In 1952 at 18 yo, I scored a 98 on the AFQT. If I could produce that
test page today I'd be an automatic Mensa member. Part of that
degradation was a pulmonary embolism that starved my brain in and out of
reality for several hours while the clot buster shot was working when I
was 79. Survival rates for one of those things is very poor.
The next best score out of 136 boys that day was 37. They were looking
for machine gun targets for Korea at the time, so that 98 got me 4F'd
because they knew I would not follow orders. I thought goody, found me a
good woman, and got on with life.
So yes, I need to talk to intelligent life.
Cheers, Gene Heskett
--
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
- Louis D. Brandeis
Genes Web page <http://geneslinuxbox.net:6309/gene>
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