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 X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FAKE_REPLY_C,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 799E0C43331 for ; Sat, 9 Nov 2019 18:45:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 43FF0214E0 for ; Sat, 9 Nov 2019 18:45:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="UGh3WLA4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726424AbfKISor (ORCPT ); Sat, 9 Nov 2019 13:44:47 -0500 Received: from mail-wr1-f45.google.com ([209.85.221.45]:46607 "EHLO mail-wr1-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726227AbfKISoq (ORCPT ); Sat, 9 Nov 2019 13:44:46 -0500 Received: by mail-wr1-f45.google.com with SMTP id b3so10446938wrs.13 for ; Sat, 09 Nov 2019 10:44:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:mime-version:content-disposition :user-agent; bh=4XI1X85wLVzP/SrohCDsY8Ew06poMLmDa6mRwgBF9Dw=; b=UGh3WLA4/FFSWy1DOkfxzZ2Vr8RzGE9s4D8t0HYzUs4MplEI/CF6V5BrEsAB6wwR3Y fYlK+IwMc70dU9xz8nUW2+FLqvPVGSIUx2L8QxVyNUaFQb3s4e9sZf+QXFHVM9e1xcBV 8qQklAOVTXh9pu5CXQG2GOuKC8L8jnhld/OZZx9nSZeAJiTI5ZWmcAJ8EVju6wmJMJjb v+jS7/uToRUK3F3UajUM6+lovqbjkWQuBtyDXbTj19I8EAfsUa0b8SaO98codT5iNM0N jfcGEPdHMVkP1m440anr4jbipVfBHT2mCQs9T7Qrz9BpgtXLRSPg48yKO5PbsvHAdrxS jeKQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=4XI1X85wLVzP/SrohCDsY8Ew06poMLmDa6mRwgBF9Dw=; b=dAniTLMdXGiNYTLsWrJFiI5znppY7s/PCAJMPDoi+bMZhudPpgaB+JNlZGbxiZa1QW UQBF7uQc9yDt6/fKE8mQ6P1pYWJIpmkGF0dYucMdN13U1nqEMev34sPEFPo1rOwjWiBV izDcPLsPCoSLey+QEN1sU1UJ+BdH61pK9eQ9mCfqkzK5k7M8X3LLXe7MzfeMKRDFg8a4 RoxO32/R4CR7FGbCW+CkhsFYnk2sa8Rp6U51HDtm8uNVKGfevyrkkJnrUSnRgbdbJPVG KddMhj4xoLTKMivE5b/FAfJZJJeVJA0dqUFVU+HpSKyR+zqxhaEzOWtOcSw1vIxGkJdH qLlw== X-Gm-Message-State: APjAAAXjqUROQW+SxcIU0AVqRuqy24CjZrn6BBYvbaqaqZndT/nUlBi2 guzcZy86w1w2kEzeYXQbGw== X-Google-Smtp-Source: APXvYqzv32EA1qkivhRH6rX7beyDR0RoTDaST3JRt0IsupMyx0C8u9NjxXcLpyYy9nT1yeZY30bkhQ== X-Received: by 2002:adf:ebd2:: with SMTP id v18mr13239145wrn.71.1573325084384; Sat, 09 Nov 2019 10:44:44 -0800 (PST) Received: from avx2 ([46.53.254.55]) by smtp.gmail.com with ESMTPSA id j10sm4456103wrx.30.2019.11.09.10.44.43 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 09 Nov 2019 10:44:43 -0800 (PST) Date: Sat, 9 Nov 2019 21:44:41 +0300 From: Alexey Dobriyan To: pbonzini@redhat.com, gregkh@linuxfoundation.org Cc: linux-kernel@vger.kernel.org Subject: Re: "statsfs" API design Message-ID: <20191109184441.GA5092@avx2> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > statsfs is a proposal for a new Linux kernel synthetic filesystem, > to be mounted in /sys/kernel/stats I think /proc experiment teaches pretty convincingly that dressing things into a filesystem can be done but ultimately is a stupid idea. It adds so much overhead for small-to-medium systems. > The first user of statsfs would be KVM, which is currently exposing > its stats in debugfs > Google has KVM patches to gather statistics in a binary format Which is a right thing to do.