[Vm-dev] ulimit rat-rio setting (was Re: [OpenSmalltalk/opensmalltalk-vm] Do not use linux-latest runner, use an older stable version. (#598))
David T. Lewis
lewis at mail.msen.com
Thu Sep 30 00:32:00 UTC 2021
On Tue, Sep 28, 2021 at 03:12:29PM -0700, tim Rowledge wrote:
> This reminds me to ask (probably again) if anyone actually understands
> ubuntu and getting the rtprio settings to 'take'.
> I have the suggested /etc/security/limits.d/squeak.conf etc but it
> appears to be ignored - at least the VM complains about it. Since
> `ulimit -a` tells me that rtprio is 0, I suspect it is correct to
> complain. I've spent way too long trying to make sense of what I
> find with googling. This has been going on for ages (so, yes, the
> machine has been rebooted) and every now and then I try to make some
> sense of it.
Aside from the various discussions of how to work around this problem,
I would expect that the VM might better do something like this:
- Attempt to start the heartbeat thread at elevated priority.
- If successful, proceed as before (other threads at normal priority)
- If not successful, drop the process priority and start all other
threads at a lower priority.
Note that running at lower priority does not affect performance or
user experience for most users. You can verify this yourself by running
Squeak at lower priority using the "nice" command, and see if you can
notice any difference.
I have not looked at how to implement the above, but my expectation
is that the strategy would give good results for most users, while
eliminating the need for root access for first-time users installing
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