commit 4d8078571906932c496ddeda541fb4b026fd12f5
author Hyman Huang(黄勇) <yong.huang@smartx.com> Wed Jun 07 21:32:59 2023 +0800
committer Juan Quintela <quintela@redhat.com> Wed Jul 26 10:55:56 2023 +0200
tree 9aaf6e2001fa7eeb94a5270d3fb57388049d97c3
parent 140e5a7632beb2adbc72066ca2d7146a7bdb2ec5

qapi/migration: Introduce x-vcpu-dirty-limit-period parameter

Introduce "x-vcpu-dirty-limit-period" migration experimental
parameter, which is in the range of 1 to 1000ms and used to
make dirtyrate calculation period configurable.

Currently with the "x-vcpu-dirty-limit-period" varies, the
total time of live migration changes, test results show the
optimal value of "x-vcpu-dirty-limit-period" ranges from
500ms to 1000 ms. "x-vcpu-dirty-limit-period" should be made
stable once it proves best value can not be determined with
developer's experiments.

Signed-off-by: Hyman Huang(黄勇) <yong.huang@smartx.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <168618975839.6361.17407633874747688653-2@git.sr.ht>
Signed-off-by: Juan Quintela <quintela@redhat.com>

migration/options.c

diff --git a/migration/options.c b/migration/options.c
index 5a9505a..1de63ba 100644
--- a/migration/options.c
+++ b/migration/options.c
@@ -80,6 +80,8 @@
 #define DEFINE_PROP_MIG_CAP(name, x)             \
     DEFINE_PROP_BOOL(name, MigrationState, capabilities[x], false)
 
+#define DEFAULT_MIGRATE_VCPU_DIRTY_LIMIT_PERIOD     1000    /* milliseconds */
+
 Property migration_properties[] = {
     DEFINE_PROP_BOOL("store-global-state", MigrationState,
                      store_global_state, true),
@@ -163,6 +165,9 @@
     DEFINE_PROP_STRING("tls-creds", MigrationState, parameters.tls_creds),
     DEFINE_PROP_STRING("tls-hostname", MigrationState, parameters.tls_hostname),
     DEFINE_PROP_STRING("tls-authz", MigrationState, parameters.tls_authz),
+    DEFINE_PROP_UINT64("x-vcpu-dirty-limit-period", MigrationState,
+                       parameters.x_vcpu_dirty_limit_period,
+                       DEFAULT_MIGRATE_VCPU_DIRTY_LIMIT_PERIOD),
 
     /* Migration capabilities */
     DEFINE_PROP_MIG_CAP("x-xbzrle", MIGRATION_CAPABILITY_XBZRLE),
@@ -908,6 +913,9 @@
                        s->parameters.block_bitmap_mapping);
     }
 
+    params->has_x_vcpu_dirty_limit_period = true;
+    params->x_vcpu_dirty_limit_period = s->parameters.x_vcpu_dirty_limit_period;
+
     return params;
 }
 
@@ -940,6 +948,7 @@
     params->has_announce_max = true;
     params->has_announce_rounds = true;
     params->has_announce_step = true;
+    params->has_x_vcpu_dirty_limit_period = true;
 }
 
 /*
@@ -1100,6 +1109,15 @@
     }
 #endif
 
+    if (params->has_x_vcpu_dirty_limit_period &&
+        (params->x_vcpu_dirty_limit_period < 1 ||
+         params->x_vcpu_dirty_limit_period > 1000)) {
+        error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
+                   "x-vcpu-dirty-limit-period",
+                   "a value between 1 and 1000");
+        return false;
+    }
+
     return true;
 }
 
@@ -1199,6 +1217,11 @@
         dest->has_block_bitmap_mapping = true;
         dest->block_bitmap_mapping = params->block_bitmap_mapping;
     }
+
+    if (params->has_x_vcpu_dirty_limit_period) {
+        dest->x_vcpu_dirty_limit_period =
+            params->x_vcpu_dirty_limit_period;
+    }
 }
 
 static void migrate_params_apply(MigrateSetParameters *params, Error **errp)
@@ -1317,6 +1340,11 @@
             QAPI_CLONE(BitmapMigrationNodeAliasList,
                        params->block_bitmap_mapping);
     }
+
+    if (params->has_x_vcpu_dirty_limit_period) {
+        s->parameters.x_vcpu_dirty_limit_period =
+            params->x_vcpu_dirty_limit_period;
+    }
 }
 
 void qmp_migrate_set_parameters(MigrateSetParameters *params, Error **errp)