From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail1.windriver.com (mail1.windriver.com [147.11.146.13]) by dpdk.org (Postfix) with ESMTP id D387CB0A6 for ; Fri, 13 Jun 2014 23:02:19 +0200 (CEST) Received: from ALA-HCA.corp.ad.wrs.com (ala-hca.corp.ad.wrs.com [147.11.189.40]) by mail1.windriver.com (8.14.5/8.14.5) with ESMTP id s5DL2YTG023307 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=FAIL) for ; Fri, 13 Jun 2014 14:02:34 -0700 (PDT) Received: from ALA-MBA.corp.ad.wrs.com ([169.254.2.48]) by ALA-HCA.corp.ad.wrs.com ([147.11.189.40]) with mapi id 14.03.0169.001; Fri, 13 Jun 2014 14:02:34 -0700 From: "Gooch, Stephen" To: "dev@dpdk.org" Thread-Topic: mmap() hint address Thread-Index: Ac+HSjModLMx+SPRQcmV/p2lSa3M/A== Date: Fri, 13 Jun 2014 21:02:33 +0000 Message-ID: <9205DC19ECCD944CA2FAC59508A772BABCEFF60C@ALA-MBA.corp.ad.wrs.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [147.11.118.60] MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Subject: [dpdk-dev] mmap() hint address X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 13 Jun 2014 21:02:20 -0000 Hello, I have seen a case where a secondary DPDK process tries to map uio resource= in which mmap() normally sends the corresponding virtual address as a hint= address. However on some instances mmap() returns a virtual address that = is not the hint address, and it result in rte_panic() and the secondary pro= cess goes defunct. This happens from time to time on an embedded device when nr_hugepages is s= et to 128, but never when nr_hugepage is set to 256 on the same device. = My question is, if mmap() can find the correct memory regions when hugepage= s is set to 256, would it not require less resources (and therefore be more= likely to pass) at a lower value such as 128? Any ideas what would cause this mmap() behavior at a lower nr_hugepage valu= e? - Stephen