Multifd sender thread performs zero page checking. If a page is
a zero page, only the page's metadata is sent to the receiver.
If a page is a normal page, the entire page's content is sent to
the receiver. This change adds a test hook to set the normal page
ratio. A zero page will be forced to be sent as a normal page. This
is useful for live migration performance analysis and optimization.
Signed-off-by: Hao Xiang <hao.xi...@bytedance.com>
---
migration/options.c | 31 +++++++++++++++++++++++++++++++
migration/options.h | 1 +
qapi/migration.json | 18 +++++++++++++++---
3 files changed, 47 insertions(+), 3 deletions(-)
diff --git a/migration/options.c b/migration/options.c
index 6e424b5d63..e7f1e2df24 100644
--- a/migration/options.c
+++ b/migration/options.c
@@ -79,6 +79,11 @@
#define DEFAULT_MIGRATE_ANNOUNCE_ROUNDS 5
#define DEFAULT_MIGRATE_ANNOUNCE_STEP 100
+/*
+ * Parameter for multifd normal page test hook.
+ */
+#define DEFAULT_MIGRATE_MULTIFD_NORMAL_PAGE_RATIO 101
+
#define DEFINE_PROP_MIG_CAP(name, x) \
DEFINE_PROP_BOOL(name, MigrationState, capabilities[x], false)
@@ -181,6 +186,9 @@ Property migration_properties[] = {
MIG_MODE_NORMAL),
DEFINE_PROP_STRING("multifd-dsa-accel", MigrationState,
parameters.multifd_dsa_accel),
+ DEFINE_PROP_UINT8("multifd-normal-page-ratio", MigrationState,
+ parameters.multifd_normal_page_ratio,
+ DEFAULT_MIGRATE_MULTIFD_NORMAL_PAGE_RATIO),
/* Migration capabilities */
DEFINE_PROP_MIG_CAP("x-xbzrle", MIGRATION_CAPABILITY_XBZRLE),
@@ -860,6 +868,12 @@ int migrate_multifd_channels(void)
return s->parameters.multifd_channels;
}
+uint8_t migrate_multifd_normal_page_ratio(void)
+{
+ MigrationState *s = migrate_get_current();
+ return s->parameters.multifd_normal_page_ratio;
+}
+
MultiFDCompression migrate_multifd_compression(void)
{
MigrationState *s = migrate_get_current();
@@ -1258,6 +1272,14 @@ bool migrate_params_check(MigrationParameters *params,
Error **errp)
return false;
}
+ if (params->has_multifd_normal_page_ratio &&
+ params->multifd_normal_page_ratio > 100) {
+ error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
+ "multifd_normal_page_ratio",
+ "a value between 0 and 100");
+ return false;
+ }
+
return true;
}
@@ -1378,6 +1400,11 @@ static void
migrate_params_test_apply(MigrateSetParameters *params,
assert(params->multifd_dsa_accel->type == QTYPE_QSTRING);
dest->multifd_dsa_accel = params->multifd_dsa_accel->u.s;
}
+
+ if (params->has_multifd_normal_page_ratio) {
+ dest->has_multifd_normal_page_ratio = true;
+ dest->multifd_normal_page_ratio = params->multifd_normal_page_ratio;
+ }
}
static void migrate_params_apply(MigrateSetParameters *params, Error **errp)
@@ -1528,6 +1555,10 @@ static void migrate_params_apply(MigrateSetParameters
*params, Error **errp)
assert(params->multifd_dsa_accel->type == QTYPE_QSTRING);
s->parameters.multifd_dsa_accel =
g_strdup(params->multifd_dsa_accel->u.s);
}
+
+ if (params->has_multifd_normal_page_ratio) {
+ s->parameters.multifd_normal_page_ratio =
params->multifd_normal_page_ratio;
+ }
}
void qmp_migrate_set_parameters(MigrateSetParameters *params, Error **errp)
diff --git a/migration/options.h b/migration/options.h
index 56100961a9..21e3e7b0cf 100644
--- a/migration/options.h
+++ b/migration/options.h
@@ -95,6 +95,7 @@ const char *migrate_tls_creds(void);
const char *migrate_tls_hostname(void);
uint64_t migrate_xbzrle_cache_size(void);
const char *migrate_multifd_dsa_accel(void);
+uint8_t migrate_multifd_normal_page_ratio(void);
/* parameters setters */
diff --git a/qapi/migration.json b/qapi/migration.json
index a8e3b66d6f..bb876c8325 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -882,6 +882,9 @@
# @multifd-dsa-accel: If enabled, use DSA accelerator offloading for
# certain memory operations. (since 8.2)
#
+# @multifd-normal-page-ratio: Test hook setting the normal page ratio.
+# (Since 8.2)
+#
# Features:
#
# @deprecated: Member @block-incremental is deprecated. Use
@@ -915,7 +918,8 @@
'block-bitmap-mapping',
{ 'name': 'x-vcpu-dirty-limit-period', 'features': ['unstable'] },
'vcpu-dirty-limit',
- 'mode'] }
+ 'mode',
+ 'multifd-normal-page-ratio'] }
##
# @MigrateSetParameters:
@@ -1073,6 +1077,9 @@
# @multifd-dsa-accel: If enabled, use DSA accelerator offloading for
# certain memory operations. (since 8.2)
#
+# @multifd-normal-page-ratio: Test hook setting the normal page ratio.
+# (Since 8.2)
+#
# Features:
#
# @deprecated: Member @block-incremental is deprecated. Use
@@ -1127,7 +1134,8 @@
'features': [ 'unstable' ] },
'*vcpu-dirty-limit': 'uint64',
'*mode': 'MigMode',
- '*multifd-dsa-accel': 'StrOrNull'} }
+ '*multifd-dsa-accel': 'StrOrNull',
+ '*multifd-normal-page-ratio': 'uint8'} }
##
# @migrate-set-parameters:
@@ -1305,6 +1313,9 @@
# @multifd-dsa-accel: If enabled, use DSA accelerator offloading for
# certain memory operations. (since 8.2)
#
+# @multifd-normal-page-ratio: Test hook setting the normal page ratio.
+# (Since 8.2)
+#
# Features:
#
# @deprecated: Member @block-incremental is deprecated. Use
@@ -1356,7 +1367,8 @@
'features': [ 'unstable' ] },
'*vcpu-dirty-limit': 'uint64',
'*mode': 'MigMode',
- '*multifd-dsa-accel': 'str'} }
+ '*multifd-dsa-accel': 'str',
+ '*multifd-normal-page-ratio': 'uint8'} }
##
# @query-migrate-parameters:
--
2.30.2
