From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 5AED33A5447; Fri, 8 May 2026 09:29:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778232571; cv=none; b=GQxsunkKA8hosqbA06gWp7U/QnPwZrQ9tsywF0kjKqG+namJi4OKL9ty4xx0iM/rpwkgYFQr1zok2kmdY75ZoEoLiUaMmJ9QPLEIXCHP7rf6HkjDtRNO2YRRYy/oFTKYQy5fje96SDdMA8ZuP9ryANKBKuYV4KL2pk795FKcvGw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778232571; c=relaxed/simple; bh=OWocBCiCRiNzZ55rS8SQ7rdxXEK59IvkiVjXZanqfsI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=XeTwvUJettOWfjs7P24Z+uF5FIF3ZIO/v9xBy9mGpsPni5Z8aWbIQzDwQ73cfmZQakgiFgEND520ULWMgAMt/NEoklY5M4QnplrQBOrluV7PPUSDeMWx6iDjz+soQBeFcIDU1mfz/Z2WGsDoDJe6I01hl7w2n/1DytzMqoczCAw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=cJQp5qBE; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="cJQp5qBE" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5EC471BCA; Fri, 8 May 2026 02:29:23 -0700 (PDT) Received: from [10.57.89.33] (unknown [10.57.89.33]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 026973F7B4; Fri, 8 May 2026 02:29:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1778232568; bh=OWocBCiCRiNzZ55rS8SQ7rdxXEK59IvkiVjXZanqfsI=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=cJQp5qBEs/JLgLFuzvpcp32McrOqjlMGbMXjGmHkHIXGcUNHowE+vQeYGeFv9VOh8 xG0W+EvheUw9fnBU051PPmx5gSEX3Md+Ie7b+CjyRH7ed0TgvbZH4pDkijF+Mc6fSO f7gS6TVJCk0wocRk82rbK9ZRJZb+oBn9HT7WmZuY= Message-ID: <26f2d829-1083-4cff-b737-a3701c7ddd85@arm.com> Date: Fri, 8 May 2026 10:29:24 +0100 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] sched_ext: Add scx_ai_numa scheduler example for AI workloads To: Andrea Righi , Qiliang Yuan Cc: Tejun Heo , David Vernet , Changwoo Min , linux-kernel@vger.kernel.org, sched-ext@lists.linux.dev, bpf@vger.kernel.org References: <20260508-feat-scx_ai_example-v1-1-2b498af3514d@gmail.com> Content-Language: en-US From: Christian Loehle In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 5/8/26 08:56, Andrea Righi wrote: > Hi Qiliang, > > On Fri, May 08, 2026 at 03:51:35PM +0800, Qiliang Yuan wrote: >> Implement an AI-focused NUMA-aware scheduler that optimizes task dispatch for >> GPU-accelerated AI training. The scheduler maintains per-NUMA-node dispatch >> queues to preserve L3 cache warmth and minimize remote DRAM accesses that >> would stall GPU kernel launches waiting on CPU preprocessing. >> >> Key features: >> - Per-NUMA-node DSQs (dispatch queues) to maintain cache locality >> - Idle fast path that bypasses DSQ for minimum latency >> - Per-task NUMA affinity tracking to remember task placement >> - Work stealing across nodes to prevent starvation during load imbalance >> >> The BPF component (scx_ai_numa.bpf.c) implements the core scheduler >> callbacks, while the userspace loader (scx_ai_numa.c) detects NUMA >> topology, installs the BPF program, and reports per-node dispatch >> statistics every second. >> >> This scheduler is suitable for AI training workloads where GPU command >> launches depend on rapid CPU preprocessing with minimal scheduling latency. >> >> Signed-off-by: Qiliang Yuan > > I think this would be more appropriate for inclusion in > https://github.com/sched-ext/scx. That repo no longer hosts C schedulers though, no? I guess it's trivial to convert this particular one to rust.