commit 4cbc9c7ffd95d2702cf7ffb3bfdf3f1f0ffdca07
author Li Qiang <liq3ea@gmail.com> Wed Aug 01 06:00:20 2018 -0700
committer Juan Quintela <quintela@redhat.com> Wed Aug 22 11:42:34 2018 +0200
tree c801c82f52bf803b7eae1fc360bc665ade81f26b
parent 3eb21fe9e5a06e485dbb27838422ef85f4ae7967

migrate/cpu-throttle: Add max-cpu-throttle migration parameter

Currently, the default maximum CPU throttle for migration is
99(CPU_THROTTLE_PCT_MAX). This is too big and can make a remarkable
performance effect for the guest. We see a lot of packets latency
exceed 500ms when the CPU_THROTTLE_PCT_MAX reached. This patch set
adds a new max-cpu-throttle parameter to limit the CPU throttle.

Signed-off-by: Li Qiang <liq3ea@gmail.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

hmp.c

diff --git a/hmp.c b/hmp.c
index 2aafb50..c38e8b1 100644
--- a/hmp.c
+++ b/hmp.c
@@ -339,6 +339,10 @@
         monitor_printf(mon, "%s: %u\n",
             MigrationParameter_str(MIGRATION_PARAMETER_CPU_THROTTLE_INCREMENT),
             params->cpu_throttle_increment);
+        assert(params->has_max_cpu_throttle);
+        monitor_printf(mon, "%s: %u\n",
+            MigrationParameter_str(MIGRATION_PARAMETER_MAX_CPU_THROTTLE),
+            params->max_cpu_throttle);
         assert(params->has_tls_creds);
         monitor_printf(mon, "%s: '%s'\n",
             MigrationParameter_str(MIGRATION_PARAMETER_TLS_CREDS),
@@ -1635,6 +1639,10 @@
         p->has_cpu_throttle_increment = true;
         visit_type_int(v, param, &p->cpu_throttle_increment, &err);
         break;
+    case MIGRATION_PARAMETER_MAX_CPU_THROTTLE:
+        p->has_max_cpu_throttle = true;
+        visit_type_int(v, param, &p->max_cpu_throttle, &err);
+        break;
     case MIGRATION_PARAMETER_TLS_CREDS:
         p->has_tls_creds = true;
         p->tls_creds = g_new0(StrOrNull, 1);