22.07.2019, 20:35, "Dr. David Alan Gilbert" <dgilb...@redhat.com>:
> * Yury Kotov (yury-ko...@yandex-team.ru) wrote:
>> Signed-off-by: Yury Kotov <yury-ko...@yandex-team.ru>
>
> This looks OK to me, but have you tried it on a really really overloaded
> host?
> I worry that you might skip some of the percentage steps or not hit the
> bandwidth on the small overloaded VMs we get in CI.
No, I haven't tried. I saw patchew's logs and you're absolutely right - such
problem exists. Now I'm looking for a way to fix it.
>
> Dave
>
>> ---
>> tests/migration-test.c | 119 +++++++++++++++++++++++++++++++++++++----
>> 1 file changed, 108 insertions(+), 11 deletions(-)
>>
>> diff --git a/tests/migration-test.c b/tests/migration-test.c
>> index a4feb9545d..bb69517fc8 100644
>> --- a/tests/migration-test.c
>> +++ b/tests/migration-test.c
>> @@ -241,6 +241,17 @@ static int64_t read_ram_property_int(QTestState *who,
>> const char *property)
>> return result;
>> }
>>
>> +static int64_t read_migrate_property_int(QTestState *who, const char
>> *property)
>> +{
>> + QDict *rsp_return;
>> + int64_t result;
>> +
>> + rsp_return = migrate_query(who);
>> + result = qdict_get_try_int(rsp_return, property, 0);
>> + qobject_unref(rsp_return);
>> + return result;
>> +}
>> +
>> static uint64_t get_migration_pass(QTestState *who)
>> {
>> return read_ram_property_int(who, "dirty-sync-count");
>> @@ -255,20 +266,22 @@ static void read_blocktime(QTestState *who)
>> qobject_unref(rsp_return);
>> }
>>
>> +static bool check_migration_status(QTestState *who, const char *status)
>> +{
>> + bool completed;
>> + char *current_status;
>> +
>> + current_status = migrate_query_status(who);
>> + completed = strcmp(current_status, status) == 0;
>> + g_assert_cmpstr(current_status, !=, "failed");
>> + g_free(current_status);
>> + return completed;
>> +}
>> +
>> static void wait_for_migration_status(QTestState *who,
>> const char *goal)
>> {
>> - while (true) {
>> - bool completed;
>> - char *status;
>> -
>> - status = migrate_query_status(who);
>> - completed = strcmp(status, goal) == 0;
>> - g_assert_cmpstr(status, !=, "failed");
>> - g_free(status);
>> - if (completed) {
>> - return;
>> - }
>> + while (!check_migration_status(who, goal)) {
>> usleep(1000);
>> }
>> }
>> @@ -1121,6 +1134,89 @@ static void test_migrate_fd_proto(void)
>> test_migrate_end(from, to, true);
>> }
>>
>> +static void test_migrate_auto_converge(void)
>> +{
>> + char *uri = g_strdup_printf("unix:%s/migsocket", tmpfs);
>> + QTestState *from, *to;
>> + int i;
>> + int64_t remaining, downtime;
>> +
>> + /*
>> + * We want the test to be fast enough, but stable.
>> + * Throttle percentages are chosen to cover all cases (init, increment,
>> max)
>> + */
>> + static const int64_t expected_pcts[] = { 0, 1, 51, 98 };
>> + const int64_t max_bandwidth = 200000000; /* ~200Mb/s */
>> + const int64_t downtime_limit = 50; /* 50ms */
>> + /*
>> + * We migrate through unix-socket (> 500Mb/s).
>> + * Thus, expected migration speed ~= bandwidth limit (< 500Mb/s).
>> + * So, we can predict expected_threshold
>> + */
>> + const int64_t expected_threshold = max_bandwidth * downtime_limit / 1000;
>> +
>> + if (test_migrate_start(&from, &to, uri, false, false)) {
>> + return;
>> + }
>> +
>> + migrate_set_capability(from, "auto-converge", true);
>> + migrate_set_parameter_int(from, "cpu-throttle-initial", expected_pcts[1]);
>> + migrate_set_parameter_int(from, "cpu-throttle-increment",
>> + expected_pcts[2] - expected_pcts[1]);
>> + migrate_set_parameter_int(from, "max-cpu-throttle", expected_pcts[3]);
>> +
>> + migrate_set_parameter_int(from, "max-bandwidth", max_bandwidth);
>> + migrate_set_parameter_int(from, "downtime-limit", downtime_limit);
>> +
>> + /* To check remaining size after precopy */
>> + migrate_set_capability(from, "pause-before-switchover", true);
>> +
>> + /* Wait for the first serial output from the source */
>> + wait_for_serial("src_serial");
>> +
>> + migrate(from, uri, "{}");
>> +
>> + for (i = 0; i < ARRAY_SIZE(expected_pcts); i++) {
>> + int64_t pct;
>> + pct = read_migrate_property_int(from, "cpu-throttle-percentage");
>> + g_assert_cmpint(pct, ==, expected_pcts[i]);
>> + while (pct == expected_pcts[i] && !got_stop) {
>> + usleep(1000);
>> + pct = read_migrate_property_int(from, "cpu-throttle-percentage");
>> + }
>> + /* We break out of this loop only in paused state */
>> + if (got_stop || i + 1 == ARRAY_SIZE(expected_pcts)) {
>> + /* Check unexpected throttle percentage change */
>> + g_assert_true(got_stop);
>> + /* Check unexpected converge */
>> + g_assert_cmpint(i + 1, ==, ARRAY_SIZE(expected_pcts));
>> + g_assert_true(check_migration_status(from, "pre-switchover"));
>> + }
>> + }
>> +
>> + remaining = read_ram_property_int(from, "remaining");
>> + g_assert_cmpint(remaining, <, expected_threshold);
>> +
>> + wait_command(from, "{ 'execute': 'migrate-continue' , 'arguments':"
>> + " { 'state': 'pre-switchover' } }");
>> +
>> + qtest_qmp_eventwait(to, "RESUME");
>> +
>> + wait_for_serial("dest_serial");
>> + wait_for_migration_complete(from);
>> +
>> + downtime = read_migrate_property_int(from, "downtime");
>> + /*
>> + * Actual downtime may be greater than downtime limit,
>> + * but the difference should be small enough (~20ms)
>> + */
>> + g_assert_cmpint(downtime, <, downtime_limit + 20);
>> +
>> + g_free(uri);
>> +
>> + test_migrate_end(from, to, true);
>> +}
>> +
>> int main(int argc, char **argv)
>> {
>> char template[] = "/tmp/migration-test-XXXXXX";
>> @@ -1176,6 +1272,7 @@ int main(int argc, char **argv)
>> /* qtest_add_func("/migration/ignore_shared", test_ignore_shared); */
>> qtest_add_func("/migration/xbzrle/unix", test_xbzrle_unix);
>> qtest_add_func("/migration/fd_proto", test_migrate_fd_proto);
>> + qtest_add_func("/migration/auto_converge", test_migrate_auto_converge);
>>
>> ret = g_test_run();
>>
>> --
>> 2.22.0
> --
> Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
Regards,
Yury
