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[23.128.96.18]) by mx.google.com with ESMTP id k21si6050561ioh.78.2021.05.21.12.58.57; Fri, 21 May 2021 12:59:10 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@lwn.net header.s=20201203 header.b=JXQWzTxb; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230087AbhETVSx (ORCPT + 99 others); Thu, 20 May 2021 17:18:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35728 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230093AbhETVSu (ORCPT ); Thu, 20 May 2021 17:18:50 -0400 Received: from ms.lwn.net (ms.lwn.net [IPv6:2600:3c01:e000:3a1::42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2BC40C061574; Thu, 20 May 2021 14:17:26 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:281:8300:104d::5f6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ms.lwn.net (Postfix) with ESMTPSA id BFEE12F3; Thu, 20 May 2021 21:17:25 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 ms.lwn.net BFEE12F3 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lwn.net; s=20201203; t=1621545445; bh=wEoEWkmh9unv7tC8nNiVNMD01nU61GT8xINDNNIpZYk=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=JXQWzTxbuHYe5RZPql1VxGK/csjp8yDkdjB2OFfJzruYe4Z46INES0AIUR3//LR5S GjG0UNKUivAt8YEcZTLsXm4TeF/i12cnRA3XRbyIY2SXkHgZHIPCIySwfWcShJIzy6 P9I379J0v2yl3naobXjYP8vgtDzEzhc3z6gXlPq5w4GCnjrHEyAKaLGiW1Dsk738C3 4K92b0e+l1E5Mr/VslpAo5bBfLgB6/i6GA6oj/0gaNSEfLrNuIcQfwook9tcGaPE68 46kdraHRD+s7FBPxKV4zejFBIERtUqtZXWvlvUQ1hiJvpLoigEF4CExGSucGMl91RG sl4dfyeFjjN4A== From: Jonathan Corbet To: Peter Oskolkov , Peter Zijlstra , Ingo Molnar , Thomas Gleixner , linux-kernel@vger.kernel.org, linux-api@vger.kernel.org Cc: Paul Turner , Ben Segall , Peter Oskolkov , Peter Oskolkov , Joel Fernandes , Andrew Morton , Andrei Vagin , Jim Newsome Subject: Re: [RFC PATCH v0.1 0/9] UMCG early preview/RFC patchset In-Reply-To: <20210520183614.1227046-1-posk@google.com> References: <20210520183614.1227046-1-posk@google.com> Date: Thu, 20 May 2021 15:17:25 -0600 Message-ID: <87mtspm7fe.fsf@meer.lwn.net> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Peter Oskolkov writes: > As indicated earlier in the FUTEX_SWAP patchset: > > https://lore.kernel.org/lkml/20200722234538.166697-1-posk@posk.io/ > > "Google Fibers" is a userspace scheduling framework > used widely and successfully at Google to improve in-process workload > isolation and response latencies. We are working on open-sourcing > this framework, and UMCG (User-Managed Concurrency Groups) kernel > patches are intended as the foundation of this. So I have to ask...is there *any* documentation out there on what this is and how people are supposed to use it? Shockingly, typing "Google fibers" into Google leads to a less than fully joyful outcome... This won't be easy for anybody to review if they have to start by reverse-engineering what it's supposed to do. Thanks, jon