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From: Steven Rostedt <rostedt@goodmis.org>
To: Elana Copperman <Elana.Copperman@mobileye.com>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	"Vladimir Kondratiev (Mobileye)" 
	<63dc4b5d-c467-4bfb-bce5-74485907c850@intel.mail.onmicrosoft.com>
Subject: Re: cgroups CPU time management + PREEMPT_RT
Date: Tue, 12 May 2020 09:36:12 -0400
Message-ID: <20200512093612.416899e1@gandalf.local.home> (raw)
In-Reply-To: <AM0PR09MB3794A1DA3C38B31A4A16E9DD99BE0@AM0PR09MB3794.eurprd09.prod.outlook.com>

On Tue, 12 May 2020 13:30:27 +0000
Elana Copperman <Elana.Copperman@mobileye.com> wrote:

> Hi, can you help to clarify if there is any implementation support or
> evidence on configuring cgroups CPU time allocations for RT tasks in
> conjunction with the PREEMPT_RT patch?

What exactly are you trying to do with cgroups CPU time allocations, and
what is the problem you are seeing with the PREEMPT_RT patch with them?

I'm assuming you are using the 5.6-rt kernel.

-- Steve


> 
> Or are the two requirements contradictory in essence and not jointly
> feasible?
> 
> Thanks
> 
> Elana and Vladimir
> 
> 
> 
> 
> From: Elana Copperman
> 
> Sent: Thursday, May 7, 2020 10:08 PM
> 
> To: linux-rt-users <linux-rt-users@vger.kernel.org>; Vladimir Kondratiev
> (Mobileye)
> <63dc4b5d-c467-4bfb-bce5-74485907c850@intel.mail.onmicrosoft.com>
> 
> Subject: RE: cgroups CPU time management + PREEMPT_RT
> 
>  
> 
> 
> Hi,
> 
> We are new to the mailing list, and new to PREEMPT_RT.
> 
> We are working on a project with a safety requirement to configure
> cgroups for resource management, as well as functional requirement for
> deployment of PREEMPT_RT patch.
> 
> cgroups in general can be used in this context, in particular for
> managing resources such as memory; and even for managing CPU time for
> non-RT tasks. 
> 
> 
> However, we do see a potential problem with RT tasks, and how the CPU
> controller would work with the RT scheduling.
> 
> There is some obvious concern here, and this seems to be backed by what I
> find online regarding this question.
> 
> 
> 
> Can you help us to clarify what is the current state of implementation,
> and if there is any support for cgroup CPU controller configuration to
> work effectively with PREEMPT_RT for RT tasks? 
> 
> 
> Thanks 
> 
> Elana
> 
> 
> 
> 
> 


  reply index

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <AM0PR09MB3794D873EEAE20CD9201D14299A50@AM0PR09MB3794.eurprd09.prod.outlook.com>
2020-05-07 19:08 ` Elana Copperman
     [not found]   ` <AM0PR09MB3794F5E857CB761859BBEF0B99BE0@AM0PR09MB3794.eurprd09.prod.outlook.com>
2020-05-12 13:30     ` Elana Copperman
2020-05-12 13:36       ` Steven Rostedt [this message]
2020-05-12 13:41         ` Elana Copperman
2020-05-26 14:33           ` Sebastian Andrzej Siewior
     [not found]             ` <AM0PR09MB37947DEF27E4D91EE8B0BD1A99B00@AM0PR09MB3794.eurprd09.prod.outlook.com>
2020-05-26 15:01               ` Elana Copperman

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