From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756666AbbFPQdx (ORCPT ); Tue, 16 Jun 2015 12:33:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49632 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754639AbbFPQdn (ORCPT ); Tue, 16 Jun 2015 12:33:43 -0400 From: Igor Mammedov To: linux-kernel@vger.kernel.org Cc: mst@redhat.com, kvm@vger.kernel.org, pbonzini@redhat.com Subject: [PATCH 0/5] vhost: support upto 509 memory regions Date: Tue, 16 Jun 2015 18:33:34 +0200 Message-Id: <1434472419-148742-1-git-send-email-imammedo@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Series extends vhost to support upto 509 memory regions, and adds some vhost:translate_desc() performance improvemnts so it won't regress when memslots are increased to 509. It fixes running VM crashing during memory hotplug due to vhost refusing accepting more than 64 memory regions. It's only host kernel side fix to make it work with QEMU versions that support memory hotplug. But I'll continue to work on QEMU side solution to reduce amount of memory regions to make things even better. Performance wise for guest with (in my case 3 memory regions) and netperf's UDP_RR workload translate_desc() execution time from total workload takes: Memory |1G RAM|cached|non cached regions # | 3 | 53 | 53 ------------------------------------ upstream | 0.3% | - | 3.5% ------------------------------------ this series | 0.2% | 0.5% | 0.7% where "non cached" column reflects trashing wokload with constant cache miss. More details on timing in respective patches. Igor Mammedov (5): vhost: use binary search instead of linear in find_region() vhost: extend memory regions allocation to vmalloc vhost: support upto 509 memory regions vhost: add per VQ memory region caching vhost: translate_desc: optimization for desc.len < region size drivers/vhost/vhost.c | 95 +++++++++++++++++++++++++++++++++++++-------------- drivers/vhost/vhost.h | 1 + 2 files changed, 71 insertions(+), 25 deletions(-) -- 1.8.3.1