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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9408C433FE for ; Thu, 17 Nov 2022 21:42:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240009AbiKQVmk (ORCPT ); Thu, 17 Nov 2022 16:42:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55820 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234542AbiKQVmd (ORCPT ); Thu, 17 Nov 2022 16:42:33 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 35737682A9; Thu, 17 Nov 2022 13:42:33 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C65A361E76; Thu, 17 Nov 2022 21:42:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5D9AEC433C1; Thu, 17 Nov 2022 21:42:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1668721352; bh=e4gyaeZKuN5TuhPKWwkSBb9I05Kqo8fxxhIvbwmMql4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Yu3InIqynn9YYcRssyMle8HVsrGC3Zgm+jhC+xr8d75RH6T7EqQHfvcORUScdh/KS 89m/3vCXOBaNT49RVYtd9q+km/mQvtZApDgbGXSKNDg1X8scXWwYCNp4IJau7Ox2TO S7StpMn3WR9AI49TAQ+T7PjCZWuu2bVKbcQ310vY= Date: Thu, 17 Nov 2022 22:38:36 +0100 From: Greg KH To: Anjali Kulkarni Cc: linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [RFC] Add a new generic system call which has better performance, to get /proc data, than existing mechanisms Message-ID: References: <1668623844-9114-1-git-send-email-anjali.k.kulkarni@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1668623844-9114-1-git-send-email-anjali.k.kulkarni@oracle.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 16, 2022 at 10:37:24AM -0800, Anjali Kulkarni wrote: > Currently, reading from /proc is an expensive operation, for a > performance sensitive application Then perhaps "performance sensitive applications" should not be reading 10's of thousands of /proc files? Anyway, your proposal comes up every few years, in different ways. Please research the past proposals for why this keeps failing and perhaps you should just fix up your userspace code instead? Also, look at attempts like the introduction of the readfile syscall as well, if you want to remove the open/read/close set of syscalls into one, but even that isn't all that useful for real-world applications, as you can today use the io_uring api to achieve almost the same throughput if really needed. good luck! greg k-h