From b15df1ae5063c7c181f8f068f9eba7661b3b5e1c Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Wed, 3 Jan 2018 20:20:13 +0800 Subject: migration: cleanup stats update into function We have quite a few lines in migration_thread() that calculates some statistics for the migration interations. Isolate it into a single function to improve readability. Signed-off-by: Peter Xu Reviewed-by: Juan Quintela Signed-off-by: Juan Quintela --- migration/migration.c | 86 ++++++++++++++++++++++++++++++--------------------- 1 file changed, 50 insertions(+), 36 deletions(-) (limited to 'migration/migration.c') diff --git a/migration/migration.c b/migration/migration.c index 6023218ffa..d7f85aa460 100644 --- a/migration/migration.c +++ b/migration/migration.c @@ -1303,6 +1303,8 @@ MigrationState *migrate_init(void) s->start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); s->total_time = 0; s->vm_was_running = false; + s->iteration_initial_bytes = 0; + s->threshold_size = 0; return s; } @@ -2209,6 +2211,43 @@ static void migration_calculate_complete(MigrationState *s) } } +static void migration_update_counters(MigrationState *s, + int64_t current_time) +{ + uint64_t transferred, time_spent; + int64_t threshold_size; + double bandwidth; + + if (current_time < s->iteration_start_time + BUFFER_DELAY) { + return; + } + + transferred = qemu_ftell(s->to_dst_file) - s->iteration_initial_bytes; + time_spent = current_time - s->iteration_start_time; + bandwidth = (double)transferred / time_spent; + threshold_size = bandwidth * s->parameters.downtime_limit; + + s->mbps = (((double) transferred * 8.0) / + ((double) time_spent / 1000.0)) / 1000.0 / 1000.0; + + /* + * if we haven't sent anything, we don't want to + * recalculate. 10000 is a small enough number for our purposes + */ + if (ram_counters.dirty_pages_rate && transferred > 10000) { + s->expected_downtime = ram_counters.dirty_pages_rate * + qemu_target_page_size() / bandwidth; + } + + qemu_file_reset_rate_limit(s->to_dst_file); + + s->iteration_start_time = current_time; + s->iteration_initial_bytes = qemu_ftell(s->to_dst_file); + + trace_migrate_transferred(transferred, time_spent, + bandwidth, threshold_size); +} + /* * Master migration thread on the source VM. * It drives the migration and pumps the data down the outgoing channel. @@ -2216,22 +2255,15 @@ static void migration_calculate_complete(MigrationState *s) static void *migration_thread(void *opaque) { MigrationState *s = opaque; - /* Used by the bandwidth calcs, updated later */ - int64_t initial_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); int64_t setup_start = qemu_clock_get_ms(QEMU_CLOCK_HOST); - int64_t initial_bytes = 0; - /* - * The final stage happens when the remaining data is smaller than - * this threshold; it's calculated from the requested downtime and - * measured bandwidth - */ - int64_t threshold_size = 0; bool entered_postcopy = false; /* The active state we expect to be in; ACTIVE or POSTCOPY_ACTIVE */ enum MigrationStatus current_active_state = MIGRATION_STATUS_ACTIVE; rcu_register_thread(); + s->iteration_start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); + qemu_savevm_state_header(s->to_dst_file); /* @@ -2271,17 +2303,17 @@ static void *migration_thread(void *opaque) if (!qemu_file_rate_limit(s->to_dst_file)) { uint64_t pend_post, pend_nonpost; - qemu_savevm_state_pending(s->to_dst_file, threshold_size, + qemu_savevm_state_pending(s->to_dst_file, s->threshold_size, &pend_nonpost, &pend_post); pending_size = pend_nonpost + pend_post; - trace_migrate_pending(pending_size, threshold_size, + trace_migrate_pending(pending_size, s->threshold_size, pend_post, pend_nonpost); - if (pending_size && pending_size >= threshold_size) { + if (pending_size && pending_size >= s->threshold_size) { /* Still a significant amount to transfer */ if (migrate_postcopy() && s->state != MIGRATION_STATUS_POSTCOPY_ACTIVE && - pend_nonpost <= threshold_size && + pend_nonpost <= s->threshold_size && atomic_read(&s->start_postcopy)) { if (!postcopy_start(s)) { @@ -2306,33 +2338,15 @@ static void *migration_thread(void *opaque) trace_migration_thread_file_err(); break; } + current_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); - if (current_time >= initial_time + BUFFER_DELAY) { - uint64_t transferred_bytes = qemu_ftell(s->to_dst_file) - - initial_bytes; - uint64_t time_spent = current_time - initial_time; - double bandwidth = (double)transferred_bytes / time_spent; - threshold_size = bandwidth * s->parameters.downtime_limit; - - s->mbps = (((double) transferred_bytes * 8.0) / - ((double) time_spent / 1000.0)) / 1000.0 / 1000.0; - - trace_migrate_transferred(transferred_bytes, time_spent, - bandwidth, threshold_size); - /* if we haven't sent anything, we don't want to recalculate - 10000 is a small enough number for our purposes */ - if (ram_counters.dirty_pages_rate && transferred_bytes > 10000) { - s->expected_downtime = ram_counters.dirty_pages_rate * - qemu_target_page_size() / bandwidth; - } - qemu_file_reset_rate_limit(s->to_dst_file); - initial_time = current_time; - initial_bytes = qemu_ftell(s->to_dst_file); - } + migration_update_counters(s, current_time); + if (qemu_file_rate_limit(s->to_dst_file)) { /* usleep expects microseconds */ - g_usleep((initial_time + BUFFER_DELAY - current_time)*1000); + g_usleep((s->iteration_start_time + BUFFER_DELAY - + current_time) * 1000); } } -- cgit v1.2.1