From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: Re: [PATCH 0/8] io-pgtable lock removal Date: Wed, 21 Jun 2017 17:47:26 +0200 Message-ID: <20170621154726.GQ30388@8bytes.org> References: <458ad41d-6679-eeca-3c0f-13ccb6c933b6@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Ray Jui Cc: sunil.goutham-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linu.cherian-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: iommu@lists.linux-foundation.org On Wed, Jun 14, 2017 at 05:40:30PM -0700, Ray Jui wrote: > With the NVMf target test with 4 SSDs, fio based test, random read, 4k, > 8 jobs: > > Without IOMMU: > > IOPS = 1080K > > With IOMMU, but without your latest patch: > > IOPS = 520K > > With IOMMU and your latest patch: > > IOPS = 500K ~ 850K (a lot of variation observed during the same test run) That variation might come from the RB-Tree used in the IOVA allocator. For block-device workloads the allocation size of iova ranges might be bigger than what is cached in the magazines, so that the fall-back to the old (locked) allocator is used. Joerg From mboxrd@z Thu Jan 1 00:00:00 1970 From: joro@8bytes.org (Joerg Roedel) Date: Wed, 21 Jun 2017 17:47:26 +0200 Subject: [PATCH 0/8] io-pgtable lock removal In-Reply-To: References: <458ad41d-6679-eeca-3c0f-13ccb6c933b6@codeaurora.org> Message-ID: <20170621154726.GQ30388@8bytes.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, Jun 14, 2017 at 05:40:30PM -0700, Ray Jui wrote: > With the NVMf target test with 4 SSDs, fio based test, random read, 4k, > 8 jobs: > > Without IOMMU: > > IOPS = 1080K > > With IOMMU, but without your latest patch: > > IOPS = 520K > > With IOMMU and your latest patch: > > IOPS = 500K ~ 850K (a lot of variation observed during the same test run) That variation might come from the RB-Tree used in the IOVA allocator. For block-device workloads the allocation size of iova ranges might be bigger than what is cached in the magazines, so that the fall-back to the old (locked) allocator is used. Joerg