From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from cloud48395.mywhc.ca (cloud48395.mywhc.ca [173.209.37.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 053F21AA3C5 for ; Tue, 30 Jul 2024 19:05:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=173.209.37.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722366312; cv=none; b=KDkzVr3LFJjFEjFpFU+CevRxBSW/exPqGRWdDpox81g7J/X8i5Rtqfxv3+wJvy6MakpqZulxlY1oxk2ECFC7eFays/Z+hFieQhx8EGG3SiVS4L3l2lbDeBYcM/V7htVUcpv9c6PV+XzPG8xeZDt8EXWKPBZPlkQOPR5uTBNP3Xo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722366312; c=relaxed/simple; bh=diDoPhxgOj6bZ51kFoRTCVrMhC5onP0wuHwvUZ8f5OA=; h=Message-ID:Subject:From:To:Date:In-Reply-To:References: Content-Type:MIME-Version; b=Q+PtqKuoTUbfyZKsJFlo76dJVAX1UCyjtsQ0UGPN+g+hxxyHqBljNBxENTR3wE8ReZCkPc3oyS1WvWmqaPfn5sq/iZRrnC7zfUMYny8GuTGJXS+Encr1AfIGZZJ6vK2OwPviiVcziFC4vitqLyvI5cy45O2lSri0JEZ0l/qMaus= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=trillion01.com; spf=pass smtp.mailfrom=trillion01.com; arc=none smtp.client-ip=173.209.37.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=trillion01.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=trillion01.com Received: from [45.44.224.220] (port=57816 helo=[192.168.1.177]) by cloud48395.mywhc.ca with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96.2) (envelope-from ) id 1sYs9k-0005YJ-0K; Tue, 30 Jul 2024 15:05:08 -0400 Message-ID: <4ed03237edd1c04f025065bba87f78a2059890ec.camel@trillion01.com> Subject: Re: [PATCH] io_uring: add napi busy settings to the fdinfo output From: Olivier Langlois To: Pavel Begunkov , Jens Axboe , io-uring@vger.kernel.org Date: Tue, 30 Jul 2024 15:05:07 -0400 In-Reply-To: <08e5c092-a7c4-47ca-8e4b-44acb741d1f9@gmail.com> References: <08e5c092-a7c4-47ca-8e4b-44acb741d1f9@gmail.com> Autocrypt: addr=olivier@trillion01.com; prefer-encrypt=mutual; keydata=mQINBFYd0ycBEAC53xedP1NExPwtBnDkVuMZgRiLmWoQQ8U7vEwt6HVGSsMRHx9smD76i 5rO/iCT6tDIpZoyJsTOh1h2NTn6ZkoFSn9lNOJksE77/n7HNaNxiBfvZHsuNuI53CkYFix9JhzP3t g5nV/401re30kRfA8OPivpnj6mZhU/9RTwjbVPPb8dPlm2gFLXwGPeDITgSRs+KJ0mM37fW8EatJs 0a8J1Nk8wBvT7ce+S2lOrxDItra9pW3ukze7LMirwvdMRC5bdlw2Lz03b5NrOUq+Wxv7szn5Xr9f/ HdaCH7baWNAO6H/O5LbJ3zndewokEmKk+oCIcXjaH0U6QK5gJoO+3Yt5dcTo92Vm3VMxzK2NPFXgp La7lR9Ei0hzQ0zptyFFyftt9uV71kMHldaQaSfUTsu9dJbnS2kI/j+F2S1q6dgKi3DEm0ZRGvjsSG rkgPJ5T16GI1cS2iQntawdr0A1vfXiB9xZ1SMGxL/l6js9BVlIx/CBGOJ4L190QmxJlcAZ2VnQzrl ramRUv01xb00IPJ5TBft5IJ+SY0FnY9pIERIl6w9khwLt/oGuKNmUHmzJGYoJHYfh72Mm8RQ1R/JS o6v85ULBGdEC3pQq1j//OPyH3egiXIwFq6BtULH5CvsxQkSqgj1MpjwfgVJ8VbjNwqwBXHjooEORj vFQqWQki6By3QARAQABtDJPbGl2aWVyIExhbmdsb2lzIChNeSBrZXkpIDxvbGl2aWVyQHRyaWxsaW 9uMDEuY29tPokCNwQTAQgAIQUCVh3TJwIbAwULCQgHAwUVCgkICwUWAgMBAAIeAQIXgAAKCRBlaka GGsWHEI1AD/9sbj+vnFU29WemVqB4iW+9RrHIcbXI4Jg8WaffTQ8KvVeCJ4otzgVT2nHC2A82t4PF 0tp21Ez17CKDNilMvOt8zq6ZHx36CPjoqUVjAdozOiBDpC4qB6ZKYn+gqSENO4hqmmaOW57wT9vII v6mtHmnFvgpOEJl6wbs8ArHDt0BLSjc8QQfvBhoKoWs+ijQTyvFGlQl0oWxEbUkR1J3gdft9Oj9xQ G4OFo73WaSEK/L9IalU2ulCBC+ucSP9McoDxy1i1u8HUDrV5wBY1zafc9zVBcMNH6+ZjxwQmZXqtz ATzB3RbSFHAdmvxl8q6MeS2yx7Atk0CXgW9z5k2KeuZhz5rVV5A+D19SSGzW11uYXsibZx/Wjr9xB KHB6U7qh5sRHaQS191NPonKcsXXAziR+vxwQTP7ZKfy+g5N/e6uivoUnQrl9uvUDDPXEpwVNSoVws Vn4tNyrGEdN11pHDbH5fSGzdpbY8+yczUoxMmsEQe/fpVwRBZUqafRn2TVUhV0qqzsUuQcTNw1zIZ JgvkqrHgd4ivd2b1bXBczmu/wMGpEnF6cWzSQDiwC1NF3i+gHCuD8IX1ujThWtzXsn0VtrMkrRCbn ponVQ6HcbRYYXPuK0HRRjCSuAKo5porVONepiOSmu0FBrpGqBkpBtLrzKXoi1yt/7a/wGdMcVhYGg vA== Organization: Trillion01 Inc Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.52.3 Precedence: bulk X-Mailing-List: io-uring@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - cloud48395.mywhc.ca X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - trillion01.com X-Get-Message-Sender-Via: cloud48395.mywhc.ca: authenticated_id: olivier@trillion01.com X-Authenticated-Sender: cloud48395.mywhc.ca: olivier@trillion01.com X-Source: X-Source-Args: X-Source-Dir: On Tue, 2024-07-30 at 16:33 +0100, Pavel Begunkov wrote: > On 7/29/24 23:38, Olivier Langlois wrote: > > this info may be useful when attempting to debug a problem > > involving a ring using the feature. >=20 > While on the topic of busy polling, there is a function > io_napi_adjust_timeout(), it ensures that we don't busy poll for > longer > than the passed wait timeout. >=20 > Do you use it? I have some doubts in regards to its usefulness, and > would prefer to try get rid of it if there are no users since it's a > hustle. >=20 I am not because I use NAPI busy poll exclusively from SQPOLL thread which in this context all that matters is that the feature is enabled or not. For users doing the polling through the io_uring syscall if the precision of the timeout is important for them, it might serve that purpose.