From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51271) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UnNQU-000841-Hv for qemu-devel@nongnu.org; Fri, 14 Jun 2013 02:24:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UnNQR-0000uo-7b for qemu-devel@nongnu.org; Fri, 14 Jun 2013 02:23:58 -0400 Received: from e39.co.us.ibm.com ([32.97.110.160]:47248) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UnNQR-0000uh-0B for qemu-devel@nongnu.org; Fri, 14 Jun 2013 02:23:55 -0400 Received: from /spool/local by e39.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 14 Jun 2013 00:23:54 -0600 Received: from d03relay05.boulder.ibm.com (d03relay05.boulder.ibm.com [9.17.195.107]) by d03dlp03.boulder.ibm.com (Postfix) with ESMTP id 9D8C319D8053 for ; Fri, 14 Jun 2013 00:23:43 -0600 (MDT) Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay05.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r5E6NqgP102006 for ; Fri, 14 Jun 2013 00:23:52 -0600 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r5E6Notb000745 for ; Fri, 14 Jun 2013 00:23:50 -0600 From: mrhines@linux.vnet.ibm.com Date: Fri, 14 Jun 2013 02:23:22 -0400 Message-Id: <1371191005-9349-11-git-send-email-mrhines@linux.vnet.ibm.com> In-Reply-To: <1371191005-9349-1-git-send-email-mrhines@linux.vnet.ibm.com> References: <1371191005-9349-1-git-send-email-mrhines@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH v8 10/13] rdma: introduce capability x-rdma-pin-all List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: aliguori@us.ibm.com, quintela@redhat.com, knoel@redhat.com, owasserm@redhat.com, abali@us.ibm.com, mrhines@us.ibm.com, gokul@us.ibm.com, pbonzini@redhat.com, chegu_vinod@hp.com From: "Michael R. Hines" This capability allows you to disable dynamic chunk registration for better throughput on high-performance links. For example, using an 8GB RAM virtual machine with all 8GB of memory in active use and the VM itself is completely idle using a 40 gbps infiniband link: 1. x-rdma-pin-all disabled total time: approximately 7.5 seconds @ 9.5 Gbps 2. x-rdma-pin-all enabled total time: approximately 4 seconds @ 26 Gbps These numbers would of course scale up to whatever size virtual machine you have to migrate using RDMA. Enabling this feature does *not* have any measurable affect on migration *downtime*. This is because, without this feature, all of the memory will have already been registered already in advance during the bulk round and does not need to be re-registered during the successive iteration rounds. Reviewed-by: Eric Blake Reviewed-by: Paolo Bonzini Signed-off-by: Michael R. Hines --- include/migration/migration.h | 2 ++ migration.c | 9 +++++++++ qapi-schema.json | 7 ++++++- 3 files changed, 17 insertions(+), 1 deletion(-) diff --git a/include/migration/migration.h b/include/migration/migration.h index d60c64c..2e6001d 100644 --- a/include/migration/migration.h +++ b/include/migration/migration.h @@ -125,6 +125,8 @@ void migrate_add_blocker(Error *reason); */ void migrate_del_blocker(Error *reason); +bool migrate_rdma_pin_all(void); + int xbzrle_encode_buffer(uint8_t *old_buf, uint8_t *new_buf, int slen, uint8_t *dst, int dlen); int xbzrle_decode_buffer(uint8_t *src, int slen, uint8_t *dst, int dlen); diff --git a/migration.c b/migration.c index 441a3b2..a704d48 100644 --- a/migration.c +++ b/migration.c @@ -476,6 +476,15 @@ void qmp_migrate_set_downtime(double value, Error **errp) max_downtime = (uint64_t)value; } +bool migrate_rdma_pin_all(void) +{ + MigrationState *s; + + s = migrate_get_current(); + + return s->enabled_capabilities[MIGRATION_CAPABILITY_X_RDMA_PIN_ALL]; +} + int migrate_use_xbzrle(void) { MigrationState *s; diff --git a/qapi-schema.json b/qapi-schema.json index b239adb..4e9cd6d 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -608,10 +608,15 @@ # This feature allows us to minimize migration traffic for certain work # loads, by sending compressed difference of the pages # +# @x-rdma-pin-all: Controls whether or not the entire VM memory footprint is +# mlock()'d on demand or all at once. Refer to docs/rdma.txt for usage. +# Disabled by default. Experimental: may (or may not) be renamed after +# further testing is complete. (since 1.5) +# # Since: 1.2 ## { 'enum': 'MigrationCapability', - 'data': ['xbzrle'] } + 'data': ['xbzrle', 'x-rdma-pin-all'] } ## # @MigrationCapabilityStatus -- 1.7.10.4