From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id D8384D167F7 for ; Fri, 9 Jan 2026 09:59:06 +0000 (UTC) Received: from mx.nabladev.com (mx.nabladev.com [178.251.229.89]) by mx.groups.io with SMTP id smtpd.msgproc02-g2.7079.1767952745999005913 for ; Fri, 09 Jan 2026 01:59:06 -0800 Authentication-Results: mx.groups.io; dkim=pass header.i=@nabladev.com header.s=dkim header.b=P4vdmknk; spf=pass (domain: nabladev.com, ip: 178.251.229.89, mailfrom: pavel@nabladev.com) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 9790F10A05C; Fri, 9 Jan 2026 10:59:01 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nabladev.com; s=dkim; t=1767952743; h=from:subject:date:message-id:to:cc:mime-version:content-type: in-reply-to:references; bh=qh8La9ec/dFpCl435l4Q0DJOyOwRo2etqWfw0UfZ08s=; b=P4vdmknkYDW9P9K+a1zLYNo64c/k9x+C0SQwt8d+gbf7BIxN/WH6jryzjCJD0alAjcqbjn ZHsdtx1ScHrPBmYRchGu7amRrIeGomRMgCaRL0g5V6Y/vCKj9BViWSNUngF1Iuh2fEQT1Y nuQySCcFQqVcEJ14PXlbcFJlKzRq60fI9UttNSPBoNcvX07AbD6X5SjVIqal9KS5wAEwqg LaEIoJ8MgBExMk9XCSpcKwLYE6Rtx2zHnv1gRyU68XD68pF0Lnu9EWBO0terMDzWRMAHKO oEntmcdbAr6sflOZf9KpB+dmXgvr/3OFS23Y0z7h80DHNk7wSoMuRx06cLTqoQ== Date: Fri, 9 Jan 2026 10:58:58 +0100 From: Pavel Machek To: tobias.schaffner@siemens.com Cc: cip-dev@lists.cip-project.org, nobuhiro.iwamatsu.x90@mail.toshiba, Jan Kiszka , Jan Altenberg Subject: Re: [cip-dev] preempt_rt on BeagleV-Fire Message-ID: References: <36dd7fca-98e9-49ab-8dca-14a3997d0c5f@siemens.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="xoAVZb08zxHnCwSK" Content-Disposition: inline In-Reply-To: <36dd7fca-98e9-49ab-8dca-14a3997d0c5f@siemens.com> X-Last-TLS-Session-Version: TLSv1.3 List-Id: X-Webhook-Received: from 45-33-107-173.ip.linodeusercontent.com [45.33.107.173] by aws-us-west-2-korg-lkml-1.web.codeaurora.org with HTTPS for ; Fri, 09 Jan 2026 09:59:06 -0000 X-Groupsio-URL: https://lists.cip-project.org/g/cip-dev/message/21493 --xoAVZb08zxHnCwSK Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > has anyone already tested preempt_rt on the BeagleV-Fire? >=20 > OSADL has evaluated preempt_rt on both the PolarFire Icicle Kit > (MPFS250T) and the PolarFire Discovery Kit (MPFS095T) and has reported > rather problematic latency results so far[1]. >=20 > Since the BeagleV-Fire is also based on a PolarFire SoC (MPFS025T), I > suspect we might run into similar issues. Any experiences, measurements, > or insights would be greatly appreciated. Those OSADL results actually look good to me :-). Ok, so let me explain. BeagleV-Fire seems to have slow CPUs. Like "Nokia N900" slow. That's TI OMAP 3430 SoC, 600 MHz ARM Cortex-A8 CPU =66rom 2010 or so. It is certainly less than 10% of speed of Core i9-9900K, and that one reaches 100usec... https://www.osadl.org/Latency-plot-of-system-in-rack-0-slot.qa-latencyplot-= r0s5.0.html?latencies=3D&showno=3D&shadow=3D1&slider=3D360 =2E..so 350usec is actually not that bad, AFAICT. Not sure what our requirements are, sometimes people put the time-critical stuff into FPGA. Best regards, Pavel --=20 In cooperation with Nabla. --xoAVZb08zxHnCwSK Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABECAB0WIQRPfPO7r0eAhk010v0w5/Bqldv68gUCaWDRYgAKCRAw5/Bqldv6 8scmAJ9eVED22EAyDQYvDUTxeziGteIK8QCfe0ivS4h2wlbBmLvVqrk+ByHrpg0= =iET3 -----END PGP SIGNATURE----- --xoAVZb08zxHnCwSK--