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 lists.lttng.org (lists.lttng.org [158.69.130.29]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 501C8F4181F for ; Mon, 9 Mar 2026 17:10:23 +0000 (UTC) ARC-Filter: OpenARC Filter v1.2.1 lists.lttng.org 4fV3Rc1WSQz1ZRM ARC-Seal: i=1; d=lists.lttng.org; s=arc1; a=rsa-sha256; cv=none; t=1773076222; b=T1xiiAqKXu90MMvNmXnqjuKQftIIgqGe/xeU5hsDvv5Ja01YQ0ULQcIJUsGwrDWW/7SN aIB38vuHV2BJ7UKIxSCxvYz68yEeViFa+au0xg78kHoapSRhUtYNUfP4ovmDSnwK0Nkol MfpOz+IVsc37eaLhXeioBYDz8BiMDja+j+SMmsVYesg58yZf6UlnWo73wpU5rGVRqO2mK SAdhjcVFO6lIKPvDyB9AjGq5r84ezD6xYEJ6/rCq4mx05sSOYI2yr0LwAOmp6GY7/nBme 6Nfv8MRLKOwVgayLf+zalDPcaUC2Ww4am/F3o/cYo7fTozIdOBnens4Mks8hFeKyfOg== ARC-Message-Signature: i=1; d=lists.lttng.org; s=arc1; a=rsa-sha256; c=relaxed/simple; t=1773076222; h=DKIM-Signature:Date:To:Subject:Message-ID:MIME-Version:From:From; bh=EUsve3+iBahDPvQCNSwPfR3R5f03tCHXogkdeCcNqO4=; b=H3k0+Ysd6TvJ/Taj7Dbpgq1iuxcSvY/3TxBKas3FyutEUl40cBT62yroBm9/MbCnxDgn yLtZ9Y67zSSE62gqpn6SrkynLztWP9EgSlFzPYkt1RxvTFINhbn4GbAt5F1eRQhOnAkT+ daoVMfxtEeAqG1lj6JFMKPsDggseEnlQX+QMJnFqGccm0DOMsiuszMbvNmRGWoEEu5zyc JCcMKZ3u1No5zJtMEUhpaI85in1UVq3p67qNEDWDGDfw/8xrpk4I2cFnPBVV5iEarTK6f XQ9nchUAStulgP+5aAfDAjEvk3CD5kV5zXP2XziBpWTbMXg3aV87w2C1czFJDrWpRIA== ARC-Authentication-Results: i=1; lists.lttng.org; arc=none smtp.remote-ip="::1" DKIM-Filter: OpenDKIM Filter v2.11.0 lists.lttng.org 4fV3Rc1WSQz1ZRM DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lists.lttng.org; s=default; t=1773076222; bh=EUsve3+iBahDPvQCNSwPfR3R5f03tCHXogkdeCcNqO4=; h=Date:To:Subject:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:From; b=0u17Of7Oul0FskZFW2UJdGL2a49bqmHOuRFJJEbrN1HthKd53qcadabct9biEBjv7 r8f6Gy5U9jhR/AVZH+ABTNrgykG3N7WrV0CW9Wf0t85Q4+P2M3Tp5r6Qwvv/swsENm 1HPnuKA5FnCk4xvBPQDvtjtQuUSG2u6fI2ab9vlm8POGRW92J92zk5aLLxctDtpKht R+hexfP59SFQIlpPcMk6EgDxmcVb8EvT7loIiVeh7cjWp2/mL6CFM9YriSxM/yKB+5 mDI4QaFofVGqK1kOgSTUU7m/wa8SAlG7u5i23IdlJB8X7J96mIVyFzW2nQAQwwnCoz lbbTo/QUmxj0g== Received: from lists-lttng01.efficios.com (localhost [IPv6:::1]) by lists.lttng.org (Postfix) with ESMTP id 4fV3Rc1WSQz1ZRM; Mon, 9 Mar 2026 13:10:20 -0400 (EDT) ARC-Filter: OpenARC Filter v1.2.1 lists.lttng.org 4fV3RZ110zz1ZRL DKIM-Filter: OpenDKIM Filter v2.11.0 lists.lttng.org 4fV3RZ110zz1ZRL Received: from stravinsky.debian.org (stravinsky.debian.org [IPv6:2001:41b8:202:deb::311:108]) by lists.lttng.org (Postfix) with ESMTPS id 4fV3RZ110zz1ZRL for ; Mon, 9 Mar 2026 13:10:17 -0400 (EDT) Received: from authenticated user by stravinsky.debian.org with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.94.2) (envelope-from ) id 1vze7N-002N2F-VW for lttng-dev@lists.lttng.org; Mon, 09 Mar 2026 17:10:10 +0000 Date: Mon, 9 Mar 2026 18:10:08 +0100 To: lttng-dev@lists.lttng.org Subject: Build-time tests fail if machine has a single CPU Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline X-Debian-User: sanvila X-BeenThere: lttng-dev@lists.lttng.org X-Mailman-Version: 2.1.39 Precedence: list List-Id: LTTng development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Santiago Vila via lttng-dev Reply-To: Santiago Vila Errors-To: lttng-dev-bounces@lists.lttng.org Sender: "lttng-dev" Hello. When I try to build (the Debian package of) lttng-tools (which in Debian is called ltt-control for the source package name) on AWS instances of type m7a.medium or r7a.medium (which incidentally have a single vCPU) I get the following error while running the tests: make[7]: Entering directory '/<>/tests/regression' FAIL: tools/lttng-ctl/test_robust_protocol.py 1 - test_simple - Exception: ('enable-channel --session session_lrmmg1mr --userspace channel_qmx5kx61 --buffer-allocation=per-cpu --buffer-ownership=user', '\nenable-channelfalse\n', "Error: Exception when getting CPU count: Failed to parse possible CPU mask: mask_contents=`0\n`\nError: Not enough system memory available for channel 'channel_qmx5kx61'. At least 0MiB required, 0MiB available\n") ERROR: tools/lttng-ctl/test_robust_protocol.py - exited with status 1 ERROR: ust/test_no_event_timestamps.py - Bail out! Missing 1 test cases PASS: ust/ust-constructor/test_ust_constructor_cpp_static.py 1 - Create a session FAIL: ust/ust-constructor/test_ust_constructor_cpp_static.py 2 - Add a channel to session `session_dx6uww4i` ERROR: ust/ust-constructor/test_ust_constructor_cpp_static.py - Bail out! Missing 42 test cases PASS: ust/ust-constructor/test_ust_constructor_cpp_dynamic.py 1 - Create a session FAIL: ust/ust-constructor/test_ust_constructor_cpp_dynamic.py 2 - Add a channel to session `session_nwjtsjz6` ERROR: ust/ust-constructor/test_ust_constructor_cpp_dynamic.py - Bail out! Missing 42 test cases PASS: ust/ust-constructor/test_ust_constructor_c_static.py 1 - Create a session FAIL: ust/ust-constructor/test_ust_constructor_c_static.py 2 - Add a channel to session `session_xwec7bzr` ERROR: ust/ust-constructor/test_ust_constructor_c_static.py - Bail out! Missing 22 test cases ERROR: ust/high-throughput/test_high_throughput_snapshot.py - Bail out! Missing 3 test cases SKIP: ust/high-throughput/test_high_throughput.py 1 # SKIP : Long regression tests not enabled ERROR: tools/client/test_reclaim_memory.py - Bail out! Missing 2 test cases PASS: tests.serial 1 - Test script 'tools/base-path/test_ust' returned code 0. 42 passed, 0 failed, 0 skipped, 42 planned [total: 42] FAIL: tests.serial 2 - Test script 'tools/channel/test_channel' returned code 1. 15 passed, 1 failed, 0 skipped, 16 planned [total: 16] FAIL: tests.serial 3 - Test script 'tools/channel/test_cli_legacy_channel_buffering_policies.py' returned code 1. 0 passed, 0 failed, 0 skipped, 6 planned [total: 0] Note 1: the message saying "Not enough system memory available" is probably false, as the machine has 4GB or 8GB of RAM, and I don't get those messages when using the same amount of memory with 2 CPUs. Note 2: One way to reproduce this easily on any machine is to configure GRUB with GRUB_CMDLINE_LINUX="nr_cpus=1". Thanks.