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From: David Aldrich via lttng-dev <lttng-dev@lists.lttng.org>
To: lttng-dev@lists.lttng.org
Subject: A question regarding isolated cpus and software interrupts
Date: Thu, 29 May 2025 19:06:31 +0100	[thread overview]
Message-ID: <CAJK_iej1UnwTBaJCY0WwP2g=zqEMtphgM2DUJhtKmHxNceD3yw@mail.gmail.com> (raw)

Hi

My question isn't directly related to lttng but I would welcome some advice.

Our Linux application is showing 'blips' whereby there are occasional
increases in processing times. This is for a user process that runs on
an isolated core. Using lttng and TraceCompass I have found that the
'blip' sometimes coincides with a TIMER_SOFTIRQ event on the isolated
core.

I was surprised that software interrupts may run on isolated cores. Is
there a way of preventing this?

Are there any techniques using lttng to gain more information related
to the interrupt (e.g. what is causing it)?

Best regards
David

             reply	other threads:[~2025-05-30 14:22 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-05-29 18:06 David Aldrich via lttng-dev [this message]
2025-05-30 14:49 ` Mathieu Desnoyers via lttng-dev
2025-05-30 15:00   ` David Aldrich via lttng-dev
2025-06-17 10:52 Norbert Lange via lttng-dev

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