From patchwork Thu Feb 29 18:36:27 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 19587 Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id 96F62C3260 for ; Thu, 29 Feb 2024 18:37:29 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 501B76287A; Thu, 29 Feb 2024 19:37:29 +0100 (CET) Authentication-Results: lancelot.ideasonboard.com; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="Eb9Y+4gX"; dkim-atps=neutral Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 53F7462876 for ; Thu, 29 Feb 2024 19:37:27 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1709231845; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=TEa9IZJSJV8dTI16DwvNpi0Yu5m8bealC9KMbuoPoqM=; b=Eb9Y+4gXoxxOoX8dJcbOr+q1VflBV5oNpFeJlnejEk5VoNsAoVIqPnh7ptnYXRy0R4XJx+ d/z+R/oi5z4bU75z3fgY+H96ksj5NQptdVW2XpTfT1vy/KIsp4szKhPuCUurZ9Y1Guc67w RRyABW+fasK/eAUzWxD6s5Spjl1KhCM= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-267-uD7E_nedMmKspURPuhFPog-1; Thu, 29 Feb 2024 13:37:20 -0500 X-MC-Unique: uD7E_nedMmKspURPuhFPog-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id D8F1038212E9; Thu, 29 Feb 2024 18:37:19 +0000 (UTC) Received: from shalem.redhat.com (unknown [10.39.192.10]) by smtp.corp.redhat.com (Postfix) with ESMTP id DFCB41C060AF; Thu, 29 Feb 2024 18:37:18 +0000 (UTC) From: Hans de Goede To: libcamera-devel@lists.libcamera.org Subject: [PATCH v4 16/18] libcamera: Add "Software ISP benchmarking" documentation Date: Thu, 29 Feb 2024 19:36:27 +0100 Message-ID: <20240229183654.7206-17-hdegoede@redhat.com> In-Reply-To: <20240229183654.7206-1-hdegoede@redhat.com> References: <20240229183654.7206-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.7 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Maxime Ripard , Pavel Machek , Bryan O'Donoghue Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" Add a "Software ISP benchmarking" documentation section which describes the performance/power consumption measurements used during the Software ISP's development. Signed-off-by: Hans de Goede Reviewed-by: Milan Zamazal --- Documentation/index.rst | 1 + Documentation/meson.build | 1 + Documentation/software-isp-benchmarking.rst | 82 +++++++++++++++++++++ 3 files changed, 84 insertions(+) create mode 100644 Documentation/software-isp-benchmarking.rst diff --git a/Documentation/index.rst b/Documentation/index.rst index 63fac72d..5442ae75 100644 --- a/Documentation/index.rst +++ b/Documentation/index.rst @@ -24,3 +24,4 @@ Lens driver requirements Python Bindings Camera Sensor Model + SoftwareISP Benchmarking diff --git a/Documentation/meson.build b/Documentation/meson.build index 7a58fec8..3872e0a8 100644 --- a/Documentation/meson.build +++ b/Documentation/meson.build @@ -80,6 +80,7 @@ if sphinx.found() 'lens_driver_requirements.rst', 'python-bindings.rst', 'sensor_driver_requirements.rst', + 'software-isp-benchmarking.rst', '../README.rst', ] diff --git a/Documentation/software-isp-benchmarking.rst b/Documentation/software-isp-benchmarking.rst new file mode 100644 index 00000000..d94595d5 --- /dev/null +++ b/Documentation/software-isp-benchmarking.rst @@ -0,0 +1,82 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. _software-isp-benchmarking: + +Software ISP benchmarking +========================= + +The Software ISP is particularly sensitive to performance regressions +therefore it is a good idea to always benchmark the Software ISP +before and after making changes to it and ensure that there are +no performance regressions. + +DebayerCpu class builtin benchmark +---------------------------------- + +The DebayerCpu class has a builtin benchmark. This benchmark +measures the time spent on processing (collecting statistics +and debayering) only, it does not measure the time spent on +capturing or outputting the frames. + +The builtin benchmark always runs. So this can be used by simply +running "cam" or "qcam" with a pipeline using the Software ISP. + +When it runs it will skip measuring the first 30 frames to +allow the caches and the CPU temperature (turbo-ing) to warm-up +and then it measures 30 fps and shows the total and per frame +processing time using an info level log message: + +.. code-block:: + + INFO Debayer debayer_cpu.cpp:907 Processed 30 frames in 244317us, 8143 us/frame + +To get stable measurements it is advised to disable any other processes which +may cause significant CPU usage (e.g. disable wifi, bluetooth and browsers). +When possible it is also advisable to disable CPU turbo-ing and +frequency-scaling. + +For example when benchmarking on a Lenovo ThinkPad X1 Yoga Gen 8, with +the charger plugged in, the CPU can be fixed to run at 2 GHz using: + +.. code-block:: + + sudo x86_energy_perf_policy --turbo-enable 0 + sudo cpupower frequency-set -d 2GHz -u 2GHz + +with these settings the builtin bench reports a processing time of ~7.8ms/frame +on this laptop for FHD SGRBG10 (unpacked) bayer data. + +Measuring power consumption +--------------------------- + +Since the Software ISP is often used on mobile devices it is also +important to measure power consumption and ensure that that does +not regress. + +For example to measure power consumption on a Lenovo ThinkPad X1 Yoga Gen 8 +it needs to be running on battery and it should be configured with its +platform-profile (/sys/firmware/acpi/platform_profile) set to balanced and +with its default turbo and frequency-scaling behavior to match real world usage. + +Then start qcam to capture a FHD picture at 30 fps and position the qcam window +so that it is fully visible. After this run the following command to monitor +the power consumption: + +.. code-block:: + + watch -n 10 cat /sys/class/power_supply/BAT0/power_now /sys/class/hwmon/hwmon6/fan?_input + +Note this not only measures the power consumption in µW it also monitors +the speed of this laptop's 2 fans. This is important because depending on +the ambient temperature the 2 fans may spin up while testing and this +will cause an additional power consumption of approx. 0.5 W messing up +the measurement. + +After starting qcam + the watch command let the laptop sit without using +it for 2 minutes for the readings to stabilize. Then check that the fans +have not turned on and manually take a couple of consecutive power readings +and avarage these. + +On the example Lenovo ThinkPad X1 Yoga Gen 8 laptop this results in +a measured power consumption of approx. 13 W while running qcam versus +approx. 4-5 W while setting idle with its OLED panel on.