From: Chris Friesen <chris.friesen@windriver.com>
To: Christian Loehle <christian.loehle@arm.com>,
daniel.lezcano@linaro.org, kgene@kernel.org,
linux-pm@vger.kernel.org
Subject: Re: question about behaviour of cpuidle on 6.6...seeing *many* missed estimates
Date: Tue, 8 Jul 2025 08:56:04 -0600 [thread overview]
Message-ID: <e32f6ab0-256a-4d8b-a0b6-3df2d9978b03@windriver.com> (raw)
In-Reply-To: <7d43a796-d831-430b-92d9-53b3d8351fb6@arm.com>
On 6/27/2025 1:49 AM, Christian Loehle wrote:
> On 6/26/25 19:26, Chris Friesen wrote:
>> Hi,
>>
>> I've got an Ice Lake server running 6.6 PREEMPT_RT, currently using the acpi_idle cpuidle driver and the "menu" governor. I'm seeing some weird behaviour with cpuidle and C-states and was hoping someone might be able to shed some light on what's happening.
>
> Does your kernel include
> 3cd2aa93674e cpuidle: menu: Avoid discarding useful information
> (since v6.6.93)?
Finally got around to testing this. It looked promising based on the
description, but in our testing this didn't resolve the issue. Still
seeing qperf latencies in the 120us range.
Can anyone else reproduce what I'm seeing? Should be pretty
straightforward to try out.
Thanks,
Chris
prev parent reply other threads:[~2025-07-08 15:30 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-06-26 18:26 question about behaviour of cpuidle on 6.6...seeing *many* missed estimates Chris Friesen
2025-06-27 7:49 ` Christian Loehle
2025-06-27 14:41 ` Chris Friesen
2025-07-08 14:56 ` Chris Friesen [this message]
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