From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id CE26442C4D; Wed, 7 Jun 2023 14:04:40 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id A65B040A84; Wed, 7 Jun 2023 14:04:40 +0200 (CEST) Received: from dkmailrelay1.smartsharesystems.com (smartserver.smartsharesystems.com [77.243.40.215]) by mails.dpdk.org (Postfix) with ESMTP id 236B740698 for ; Wed, 7 Jun 2023 14:04:39 +0200 (CEST) Received: from smartserver.smartsharesystems.com (smartserver.smartsharesys.local [192.168.4.10]) by dkmailrelay1.smartsharesystems.com (Postfix) with ESMTP id E04AB20266; Wed, 7 Jun 2023 14:04:38 +0200 (CEST) Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Subject: RE: [PATCH v10 1/2] mempool cache: add zero-copy get and put functions X-MimeOLE: Produced By Microsoft Exchange V6.5 Date: Wed, 7 Jun 2023 14:04:34 +0200 Message-ID: <98CBD80474FA8B44BF855DF32C47DC35D8799C@smartserver.smartshare.dk> In-Reply-To: <1755322.4herOUoSWf@thomas> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [PATCH v10 1/2] mempool cache: add zero-copy get and put functions Thread-Index: AdmZK1dUnuXmqZ8eRQqdHT4YZSJaAgABfQLg References: <20230224181059.338206-1-kamalakshitha.aligeri@arm.com> <20230224181059.338206-2-kamalakshitha.aligeri@arm.com> <1755322.4herOUoSWf@thomas> From: =?iso-8859-1?Q?Morten_Br=F8rup?= To: "Thomas Monjalon" , "Kamalakshitha Aligeri" Cc: , , , , , , , , , , X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org > From: Thomas Monjalon [mailto:thomas@monjalon.net] > Sent: Wednesday, 7 June 2023 12.32 >=20 > 24/02/2023 19:10, Kamalakshitha Aligeri: > > From: =3D Morten Br=F8rup >=20 > There is an equal sign inserted above. Could be removed while applying? >=20 > > > > Zero-copy access to mempool caches is beneficial for PMD = performance, and > > must be provided by the mempool library to fix [Bug 1052] without a > > performance regression. > > > > [Bug 1052]: https://bugs.dpdk.org/show_bug.cgi?id=3D1052 > > > > Bugzilla ID: 1052 >=20 > It would be fun if the bug content was a link to an email :) > More fun: refer to a place which will be deleted in some time. > Really, please explain the problem in the patch. > You can refer to the Bugzilla, but the idea must be in the patch. > Then no need for the full link. >=20 >=20 OK, how about this: Zero-copy access to mempool caches is beneficial for PMD performance. Furthermore, having a zero-copy mempool API is considered a precondition = for fixing a certain category of bugs, present in some PMDs: For = performance reasons, some PMDs had bypassed the mempool API in order to = achieve zero-copy access to the mempool cache. This can only be fixed in = those PMDs without a performance regression if the mempool library = offers zero-copy access APIs, so the PMDs can use the proper mempool API = instead of copy-pasting code from the mempool library. Furthermore, the = copy-pasted code in those PMDs has not been kept up to date with the = improvements of the mempool library, so when they bypass the mempool = API, mempool trace is missing and mempool statistics is not updated. Bugzilla ID: 1052