{"id":48886374,"url":"https://github.com/koppi/alsa-midi-latency-test","last_synced_at":"2026-04-16T05:10:02.143Z","repository":{"id":35102633,"uuid":"39277766","full_name":"koppi/alsa-midi-latency-test","owner":"koppi","description":"Measure the roundtrip delay of MIDI messages within the Advanced Linux© Sound Architecture (ALSA) subsystem","archived":false,"fork":false,"pushed_at":"2025-12-23T21:48:20.000Z","size":554,"stargazers_count":27,"open_issues_count":0,"forks_count":7,"subscribers_count":4,"default_branch":"master","last_synced_at":"2025-12-25T11:38:37.879Z","etag":null,"topics":["alsa","audio","jitter-analysis","latency-test","latency-tester","linux","midi","midi-message"],"latest_commit_sha":null,"homepage":"","language":"M4","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"gpl-2.0","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/koppi.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":".github/FUNDING.yml","license":"COPYING","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null,"zenodo":null,"notice":null,"maintainers":null,"copyright":null,"agents":null,"dco":null,"cla":null},"funding":{"github":"koppi","custom":"https://koppi.github.io"}},"created_at":"2015-07-17T22:22:31.000Z","updated_at":"2025-12-23T21:48:23.000Z","dependencies_parsed_at":"2025-05-13T16:36:50.625Z","dependency_job_id":"6110f3a3-20f4-4d40-8a90-7f4a540c7813","html_url":"https://github.com/koppi/alsa-midi-latency-test","commit_stats":null,"previous_names":[],"tags_count":4,"template":false,"template_full_name":null,"purl":"pkg:github/koppi/alsa-midi-latency-test","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/koppi%2Falsa-midi-latency-test","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/koppi%2Falsa-midi-latency-test/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/koppi%2Falsa-midi-latency-test/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/koppi%2Falsa-midi-latency-test/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/koppi","download_url":"https://codeload.github.com/koppi/alsa-midi-latency-test/tar.gz/refs/heads/master","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/koppi%2Falsa-midi-latency-test/sbom","scorecard":null,"host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":286080680,"owners_count":31872156,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2026-04-15T15:24:51.572Z","status":"online","status_checked_at":"2026-04-16T02:00:06.042Z","response_time":69,"last_error":null,"robots_txt_status":"success","robots_txt_updated_at":"2025-07-24T06:49:26.215Z","robots_txt_url":"https://github.com/robots.txt","online":true,"can_crawl_api":true,"host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["alsa","audio","jitter-analysis","latency-test","latency-tester","linux","midi","midi-message"],"created_at":"2026-04-16T05:10:01.433Z","updated_at":"2026-04-16T05:10:02.100Z","avatar_url":"https://github.com/koppi.png","language":"M4","funding_links":["https://github.com/sponsors/koppi","https://koppi.github.io"],"categories":[],"sub_categories":[],"readme":"``alsa-midi-latency-test`` is a Linux©-based tool used to measure the roundtrip delay of MIDI messages within the ALSA (Advanced Linux© Sound Architecture) subsystem.\n\nThe tool utilizes a high-precision timer to calculate the time it takes for a MIDI message to travel from the ALSA source to the ALSA sink, and back. It's a helpful way to understand and troubleshoot MIDI latency issues, often in situations where noticeable delay is encountered between playing a MIDI keyboard and hearing the sound. \n\n![alsa-midi-latency-test](https://raw.github.com/koppi/alsa-midi-latency-test/master/alsa-midi-latency-test.gif \"alsa-midi-latency-test\")\n\n* **Roundtrip Measurement**\n\n  The tool measures the total time it takes for a MIDI message to complete a round trip, meaning from the output of one device to the input of another.\n\n* **High-Precision Timer**\n\n  It uses a high-precision timer to accurately measure the delay, which is crucial for precise latency measurements. \n\n* **ALSA Subsystem Focus**\n  \n  The tool specifically focuses on the ALSA subsystem, allowing users to diagnose latency issues related to Linux's© audio/MIDI infrastructure.\n\nHow alsa-midi-latency-test can help:\n\n* **Diagnosing MIDI Latency**\n\n  The tool can help users pinpoint the source of latency, whether it's related to the MIDI hardware, software drivers, or system configuration. \n\n* **Optimizing ALSA Settings**\n\n  The measurements can guide users in adjusting ALSA settings, such as buffer sizes, to minimize latency.\n\n* **Identifying System Bottlenecks**\n\n  In some cases, latency can be a result of system limitations, and ``alsa-midi-latency-test`` can help identify those bottlenecks.\n\nIn summary, ``alsa-midi-latency-test`` is a valuable tool for anyone working with MIDI and ALSA on Linux©, allowing them to measure and troubleshoot latency issues effectively. \n\n## Install from source code\n```shell\ngit clone https://github.com/koppi/alsa-midi-latency-test.git\ncd alsa-midi-latency-test/\n```\nThe following packages are required to build alsa-midi-latency-test:\n```shell\nsudo apt -y install debhelper autotools-dev automake libasound2-dev\n```\nCompile alsa-midi-latency-test as follows:\n```shell\nsh autogen.sh\n./configure\nmake\n```\nInstall alsa-midi-latency-test as follows:\n```shell\nsudo make install\n```\nor build and install a Debian / Ubuntu package:\n```shell\nsudo apt -y install devscripts\ndebuild -uc -us\nsudo dpkg -i ../alsa-midi-latency-test*.deb\n```\n\n## Run alsa-midi-latency-test\n * ``` alsa-midi-latency-test -l ```\n\n   Lists available MIDI input and output ports.\n\n * ``` alsa-midi-latency-test -i [input port] -o [output port] ```\n\n   This runs the benchmark with the given input and output port. Note, that the\n   input and output ports have to be connected using a MIDI cable in the real\n   hardware to loop the MIDI message back.\n\n * ``` man alsa-midi-latency-test ```\n\n   The man page contains documentation for all available command line switches.\n\n### Benchmarking Results\n\n   Please share your results in the [Wiki](../../wiki/).\n\n### Definitions\n\n * [Wikipedia EN - Latency in engineering](http://tinyurl.com/wikipedia-latency-engineering)\n * [Wikipedia EN - Latency with audio](http://tinyurl.com/wikipedia-latency-audio)\n\n## See also\n\n * http://lists.linuxaudio.org/listinfo/linux-audio-tuning\n\n   The linux-audio tuning (LAT) mailing list is to help GNU/Linux© distribution\n   maintainers  and  other interested users to share information on system\n   performance tuning matters, especially with regard to real-time Linux©\n   kernels.\n\n * http://www.alsa-project.org\n\n   The Advanced Linux© Sound Architecture.\n\n * [http://www.evc-soft.nl/evc/products/miditest](http://web.archive.org/web/20061128213256/http://www.evc-soft.nl/evc/products/miditest)\n\n   The MidiTest software for Microsoft Windows.\n\n * https://codeberg.org/rtcqs/rtcqs\n\n   rtcqs is a Python utility to analyze your system and detect possible bottlenecks that could have a negative impact on the performance of your system when working with Linux© audio.\n\n## Thanks to\n\n * [Arnout Engelen](https://github.com/raboof) for initial testing,\n * [Clemens Ladisch](https://github.com/cladisch) for a number of fixes with the high precision timer and ALSA midi event handling,\n * [Giulio Moro](https://github.com/giuliomoro) for code cleanup, various fixes and support for UART I/O.\n\n## BUGS and AUTHORS\n\nPlease [report bugs](https://github.com/koppi/alsa-midi-latency-test/issues) to the authors:\n\n * [Jakob Flierl](https://github.com/koppi)\n\nLast updated Apr 2026.\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fkoppi%2Falsa-midi-latency-test","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fkoppi%2Falsa-midi-latency-test","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fkoppi%2Falsa-midi-latency-test/lists"}