From 9e1ba4cc4e2536d9650e84e2614c5691ed45938f Mon Sep 17 00:00:00 2001
From: Orit Wasserman <owasserm@redhat.com>
Date: Mon, 6 Aug 2012 21:42:54 +0300
Subject: [PATCH] Add migrate_set_cache_size command
Change XBZRLE cache size in bytes (the size should be a power of 2, it will be
rounded down to the nearest power of 2).
If XBZRLE cache size is too small there will be many cache miss.
New query-migrate-cache-size QMP command and 'info migrate_cache_size' HMP
command to query cache value.
Signed-off-by: Benoit Hudzia <benoit.hudzia@sap.com>
Signed-off-by: Petter Svard <petters@cs.umu.se>
Signed-off-by: Aidan Shribman <aidan.shribman@sap.com>
Signed-off-by: Orit Wasserman <owasserm@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
arch_init.c | 10 ++++++++++
hmp-commands.hx | 22 ++++++++++++++++++++++
hmp.c | 19 +++++++++++++++++++
hmp.h | 2 ++
migration.c | 19 +++++++++++++++++++
migration.h | 2 ++
monitor.c | 7 +++++++
qapi-schema.json | 27 +++++++++++++++++++++++++++
qmp-commands.hx | 44 ++++++++++++++++++++++++++++++++++++++++++++
9 files changed, 152 insertions(+)
diff --git a/arch_init.c b/arch_init.c
index 8cff9c608f..7fbfe91ad5 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -191,6 +191,16 @@ static struct {
.cache = NULL,
};
+
+int64_t xbzrle_cache_resize(int64_t new_size)
+{
+ if (XBZRLE.cache != NULL) {
+ return cache_resize(XBZRLE.cache, new_size / TARGET_PAGE_SIZE) *
+ TARGET_PAGE_SIZE;
+ }
+ return pow2floor(new_size);
+}
+
static void save_block_hdr(QEMUFile *f, RAMBlock *block, ram_addr_t offset,
int cont, int flag)
{
diff --git a/hmp-commands.hx b/hmp-commands.hx
index 476b3cda2e..f6104b099f 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -829,6 +829,26 @@ STEXI
@item migrate_cancel
@findex migrate_cancel
Cancel the current VM migration.
+
+ETEXI
+
+ {
+ .name = "migrate_set_cache_size",
+ .args_type = "value:o",
+ .params = "value",
+ .help = "set cache size (in bytes) for XBZRLE migrations,"
+ "the cache size will be rounded down to the nearest "
+ "power of 2.\n"
+ "The cache size affects the number of cache misses."
+ "In case of a high cache miss ratio you need to increase"
+ " the cache size",
+ .mhandler.cmd = hmp_migrate_set_cache_size,
+ },
+
+STEXI
+@item migrate_set_cache_size @var{value}
+@findex migrate_set_cache_size
+Set cache size to @var{value} (in bytes) for xbzrle migrations.
ETEXI
{
@@ -1433,6 +1453,8 @@ show user network stack connection states
show migration status
@item info migrate_capabilities
show current migration capabilities
+@item info migrate_cache_size
+show current migration XBZRLE cache size
@item info balloon
show balloon information
@item info qtree
diff --git a/hmp.c b/hmp.c
index 2a03b446a1..8abb4bddb3 100644
--- a/hmp.c
+++ b/hmp.c
@@ -194,6 +194,12 @@ void hmp_info_migrate_capabilities(Monitor *mon)
qapi_free_MigrationCapabilityStatusList(caps);
}
+void hmp_info_migrate_cache_size(Monitor *mon)
+{
+ monitor_printf(mon, "xbzrel cache size: %" PRId64 " kbytes\n",
+ qmp_query_migrate_cache_size(NULL) >> 10);
+}
+
void hmp_info_cpus(Monitor *mon)
{
CpuInfoList *cpu_list, *cpu;
@@ -764,6 +770,19 @@ void hmp_migrate_set_downtime(Monitor *mon, const QDict *qdict)
qmp_migrate_set_downtime(value, NULL);
}
+void hmp_migrate_set_cache_size(Monitor *mon, const QDict *qdict)
+{
+ int64_t value = qdict_get_int(qdict, "value");
+ Error *err = NULL;
+
+ qmp_migrate_set_cache_size(value, &err);
+ if (err) {
+ monitor_printf(mon, "%s\n", error_get_pretty(err));
+ error_free(err);
+ return;
+ }
+}
+
void hmp_migrate_set_speed(Monitor *mon, const QDict *qdict)
{
int64_t value = qdict_get_int(qdict, "value");
diff --git a/hmp.h b/hmp.h
index 3390a9242d..6d6e53bd6e 100644
--- a/hmp.h
+++ b/hmp.h
@@ -26,6 +26,7 @@ void hmp_info_chardev(Monitor *mon);
void hmp_info_mice(Monitor *mon);
void hmp_info_migrate(Monitor *mon);
void hmp_info_migrate_capabilities(Monitor *mon);
+void hmp_info_migrate_cache_size(Monitor *mon);
void hmp_info_cpus(Monitor *mon);
void hmp_info_block(Monitor *mon);
void hmp_info_blockstats(Monitor *mon);
@@ -53,6 +54,7 @@ void hmp_migrate_cancel(Monitor *mon, const QDict *qdict);
void hmp_migrate_set_downtime(Monitor *mon, const QDict *qdict);
void hmp_migrate_set_speed(Monitor *mon, const QDict *qdict);
void hmp_migrate_set_capability(Monitor *mon, const QDict *qdict);
+void hmp_migrate_set_cache_size(Monitor *mon, const QDict *qdict);
void hmp_set_password(Monitor *mon, const QDict *qdict);
void hmp_expire_password(Monitor *mon, const QDict *qdict);
void hmp_eject(Monitor *mon, const QDict *qdict);
diff --git a/migration.c b/migration.c
index 5a5333c44b..a6c007215a 100644
--- a/migration.c
+++ b/migration.c
@@ -511,6 +511,25 @@ void qmp_migrate_cancel(Error **errp)
migrate_fd_cancel(migrate_get_current());
}
+void qmp_migrate_set_cache_size(int64_t value, Error **errp)
+{
+ MigrationState *s = migrate_get_current();
+
+ /* Check for truncation */
+ if (value != (size_t)value) {
+ error_set(errp, QERR_INVALID_PARAMETER_VALUE, "cache size",
+ "exceeding address space");
+ return;
+ }
+
+ s->xbzrle_cache_size = xbzrle_cache_resize(value);
+}
+
+int64_t qmp_query_migrate_cache_size(Error **errp)
+{
+ return migrate_xbzrle_cache_size();
+}
+
void qmp_migrate_set_speed(int64_t value, Error **errp)
{
MigrationState *s;
diff --git a/migration.h b/migration.h
index cdf6787cbd..337e2255a8 100644
--- a/migration.h
+++ b/migration.h
@@ -108,4 +108,6 @@ int xbzrle_decode_buffer(uint8_t *src, int slen, uint8_t *dst, int dlen);
int migrate_use_xbzrle(void);
int64_t migrate_xbzrle_cache_size(void);
+int64_t xbzrle_cache_resize(int64_t new_size);
+
#endif
diff --git a/monitor.c b/monitor.c
index 13b681ab48..5227cf15e3 100644
--- a/monitor.c
+++ b/monitor.c
@@ -2661,6 +2661,13 @@ static mon_cmd_t info_cmds[] = {
.help = "show current migration capabilities",
.mhandler.info = hmp_info_migrate_capabilities,
},
+ {
+ .name = "migrate_cache_size",
+ .args_type = "",
+ .params = "",
+ .help = "show current migration xbzrle cache size",
+ .mhandler.info = hmp_info_migrate_cache_size,
+ },
{
.name = "balloon",
.args_type = "",
diff --git a/qapi-schema.json b/qapi-schema.json
index e3847c870c..dd16dbd4c3 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1394,6 +1394,33 @@
##
{ 'command': 'migrate_set_speed', 'data': {'value': 'int'} }
+##
+# @migrate-set-cache-size
+#
+# Set XBZRLE cache size
+#
+# @value: cache size in bytes
+#
+# The size will be rounded down to the nearest power of 2.
+# The cache size can be modified before and during ongoing migration
+#
+# Returns: nothing on success
+#
+# Since: 1.2
+##
+{ 'command': 'migrate-set-cache-size', 'data': {'value': 'int'} }
+
+##
+# @query-migrate-cache-size
+#
+# query XBZRLE cache size
+#
+# Returns: XBZRLE cache size in bytes
+#
+# Since: 1.2
+##
+{ 'command': 'query-migrate-cache-size', 'returns': 'int' }
+
##
# @ObjectPropertyInfo:
#
diff --git a/qmp-commands.hx b/qmp-commands.hx
index a14db90bbe..e42b4e3138 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -519,6 +519,50 @@ Example:
-> { "execute": "migrate_cancel" }
<- { "return": {} }
+EQMP
+{
+ .name = "migrate-set-cache-size",
+ .args_type = "value:o",
+ .mhandler.cmd_new = qmp_marshal_input_migrate_set_cache_size,
+ },
+
+SQMP
+migrate-set-cache-size
+---------------------
+
+Set cache size to be used by XBZRLE migration, the cache size will be rounded
+down to the nearest power of 2
+
+Arguments:
+
+- "value": cache size in bytes (json-int)
+
+Example:
+
+-> { "execute": "migrate-set-cache-size", "arguments": { "value": 536870912 } }
+<- { "return": {} }
+
+EQMP
+ {
+ .name = "query-migrate-cache-size",
+ .args_type = "",
+ .mhandler.cmd_new = qmp_marshal_input_query_migrate_cache_size,
+ },
+
+SQMP
+query-migrate-cache-size
+---------------------
+
+Show cache size to be used by XBZRLE migration
+
+returns a json-object with the following information:
+- "size" : json-int
+
+Example:
+
+-> { "execute": "query-migrate-cache-size" }
+<- { "return": 67108864 }
+
EQMP
{