| Message ID | f1067c9ddca005629e64d7e77c98686612bb1f82.1729064919.git.yong.huang@smartx.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | migration: auto-converge refinements for huge VM | expand |
On Wed, Oct 16, 2024 at 03:56:44PM +0800, yong.huang@smartx.com wrote: > From: Hyman Huang <yong.huang@smartx.com> > > When VM is configured with huge memory, the current throttle logic > doesn't look like to scale, because migration_trigger_throttle() > is only called for each iteration, so it won't be invoked for a long > time if one iteration can take a long time. > > The periodic dirty sync aims to fix the above issue by synchronizing > the ramblock from remote dirty bitmap and, when necessary, triggering > the CPU throttle multiple times during a long iteration. > > This is a trade-off between synchronization overhead and CPU throttle > impact. > > Signed-off-by: Hyman Huang <yong.huang@smartx.com> > --- > migration/cpu-throttle.c | 70 +++++++++++++++++++++++++++++++++++++++- > migration/cpu-throttle.h | 14 ++++++++ > migration/migration.h | 1 + > migration/ram.c | 9 ++++-- > migration/trace-events | 1 + > 5 files changed, 92 insertions(+), 3 deletions(-) > > diff --git a/migration/cpu-throttle.c b/migration/cpu-throttle.c > index fa47ee2e21..784b51ab35 100644 > --- a/migration/cpu-throttle.c > +++ b/migration/cpu-throttle.c > @@ -28,16 +28,23 @@ > #include "qemu/main-loop.h" > #include "sysemu/cpus.h" > #include "cpu-throttle.h" > +#include "migration.h" > +#include "migration-stats.h" > +#include "options.h" > #include "trace.h" > > /* vcpu throttling controls */ > -static QEMUTimer *throttle_timer; > +static QEMUTimer *throttle_timer, *throttle_dirty_sync_timer; > static unsigned int throttle_percentage; > +static bool throttle_dirty_sync_timer_active; > > #define CPU_THROTTLE_PCT_MIN 1 > #define CPU_THROTTLE_PCT_MAX 99 > #define CPU_THROTTLE_TIMESLICE_NS 10000000 > > +/* RAMBlock dirty sync trigger every five seconds */ Maybe enrich it to say "making sure it is synchronized every five seconds"? Because it can synchronize faster if each iteration runs faster than 5sec, so just to emphasize it's a fallback sync, and only with auto converge. > +#define CPU_THROTTLE_DIRTY_SYNC_TIMESLICE_MS 5000 > + > static void cpu_throttle_thread(CPUState *cpu, run_on_cpu_data opaque) > { > double pct; > @@ -112,6 +119,7 @@ void cpu_throttle_set(int new_throttle_pct) > void cpu_throttle_stop(void) > { > qatomic_set(&throttle_percentage, 0); > + cpu_throttle_dirty_sync_timer(false); > } > > bool cpu_throttle_active(void) > @@ -124,8 +132,68 @@ int cpu_throttle_get_percentage(void) > return qatomic_read(&throttle_percentage); > } > > +void cpu_throttle_dirty_sync_timer_tick(void *opaque) > +{ > + static uint64_t prev_sync_cnt = 2; IIUC the hard coded "2" isn't needed, as long as it's guaranteed to be updated for each timer call, and you special cased "1" anyway below. > + uint64_t sync_cnt = stat64_get(&mig_stats.dirty_sync_count); > + > + if (!migrate_auto_converge()) { > + /* Stop the timer when auto converge is disabled */ > + return; I think we can try to make sure this never starts if !auto-converge, so assuming this path will never trigger in real life. > + } > + > + /* > + * The first iteration copies all memory anyhow and has no > + * effect on guest performance, therefore omit it to avoid > + * paying extra for the sync penalty. > + */ > + if (sync_cnt <= 1) { > + goto end; > + } > + > + if (sync_cnt == prev_sync_cnt) { > + trace_cpu_throttle_dirty_sync(); > + WITH_RCU_READ_LOCK_GUARD() { > + migration_bitmap_sync_precopy(false); > + } > + } > + > +end: > + prev_sync_cnt = stat64_get(&mig_stats.dirty_sync_count); > + > + timer_mod(throttle_dirty_sync_timer, > + qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL_RT) + > + CPU_THROTTLE_DIRTY_SYNC_TIMESLICE_MS); > +} > + > +static bool cpu_throttle_dirty_sync_active(void) > +{ > + return qatomic_read(&throttle_dirty_sync_timer_active); > +} > + > +void cpu_throttle_dirty_sync_timer(bool enable) > +{ > + if (enable) { > + assert(throttle_dirty_sync_timer); > + if (!cpu_throttle_dirty_sync_active()) { I suppose this can be logically racy? As I think after this patch this path can be invoked both in main thread and migration thread. The simplest way to do is to move cpu_throttle_stop() call to be under bql_lock(), so that this will be serialized by BQL. Then we can add an assertion at the entry of the function for bql_locked(). > + timer_mod(throttle_dirty_sync_timer, > + qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL_RT) + > + CPU_THROTTLE_DIRTY_SYNC_TIMESLICE_MS); > + qatomic_set(&throttle_dirty_sync_timer_active, 1); > + } > + } else { > + if (throttle_dirty_sync_timer != NULL) { IIUC throttle_dirty_sync_timer is never destroyed, aka, timer_del() only disables it. So you should probably use throttle_dirty_sync_timer_active? > + timer_del(throttle_dirty_sync_timer); > + qatomic_set(&throttle_dirty_sync_timer_active, 0); > + } > + } > +} > + > void cpu_throttle_init(void) > { > throttle_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL_RT, > cpu_throttle_timer_tick, NULL); > + throttle_dirty_sync_timer = > + timer_new_ms(QEMU_CLOCK_VIRTUAL_RT, > + cpu_throttle_dirty_sync_timer_tick, NULL); > } > diff --git a/migration/cpu-throttle.h b/migration/cpu-throttle.h > index d65bdef6d0..420702b8d3 100644 > --- a/migration/cpu-throttle.h > +++ b/migration/cpu-throttle.h > @@ -65,4 +65,18 @@ bool cpu_throttle_active(void); > */ > int cpu_throttle_get_percentage(void); > > +/** > + * cpu_throttle_dirty_sync_timer_tick: > + * > + * Dirty sync timer hook. > + */ > +void cpu_throttle_dirty_sync_timer_tick(void *opaque); > + > +/** > + * cpu_throttle_dirty_sync_timer: > + * > + * Start or stop the dirty sync timer. > + */ > +void cpu_throttle_dirty_sync_timer(bool enable); > + > #endif /* SYSEMU_CPU_THROTTLE_H */ > diff --git a/migration/migration.h b/migration/migration.h > index 38aa1402d5..fbd0d19092 100644 > --- a/migration/migration.h > +++ b/migration/migration.h > @@ -537,4 +537,5 @@ int migration_rp_wait(MigrationState *s); > */ > void migration_rp_kick(MigrationState *s); > > +void migration_bitmap_sync_precopy(bool last_stage); > #endif > diff --git a/migration/ram.c b/migration/ram.c > index 9b5b350405..ac34e731e2 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -1020,6 +1020,11 @@ static void migration_trigger_throttle(RAMState *rs) > migration_transferred_bytes() - rs->bytes_xfer_prev; > uint64_t bytes_dirty_period = rs->num_dirty_pages_period * TARGET_PAGE_SIZE; > uint64_t bytes_dirty_threshold = bytes_xfer_period * threshold / 100; > + bool auto_converge = migrate_auto_converge(); > + > + if (auto_converge) { > + cpu_throttle_dirty_sync_timer(true); > + } If you have the guard to skip the 1st sync in the timer fn(), IIUC you can move this earlier to e.g. migration_thread() before iteration starts. Otherwise it'll be not as clear on when this timer will start if it hides in the sync path itself. > > /* > * The following detection logic can be refined later. For now: > @@ -1031,7 +1036,7 @@ static void migration_trigger_throttle(RAMState *rs) > if ((bytes_dirty_period > bytes_dirty_threshold) && > (++rs->dirty_rate_high_cnt >= 2)) { > rs->dirty_rate_high_cnt = 0; > - if (migrate_auto_converge()) { > + if (auto_converge) { > trace_migration_throttle(); > mig_throttle_guest_down(bytes_dirty_period, > bytes_dirty_threshold); > @@ -1088,7 +1093,7 @@ static void migration_bitmap_sync(RAMState *rs, bool last_stage) > } > } > > -static void migration_bitmap_sync_precopy(bool last_stage) > +void migration_bitmap_sync_precopy(bool last_stage) > { > Error *local_err = NULL; > assert(ram_state); > diff --git a/migration/trace-events b/migration/trace-events > index 9a19599804..0638183056 100644 > --- a/migration/trace-events > +++ b/migration/trace-events > @@ -381,3 +381,4 @@ migration_pagecache_insert(void) "Error allocating page" > > # cpu-throttle.c > cpu_throttle_set(int new_throttle_pct) "set guest CPU throttled by %d%%" > +cpu_throttle_dirty_sync(void) "" > -- > 2.27.0 >
On Thu, Oct 17, 2024 at 2:49 AM Peter Xu <peterx@redhat.com> wrote: > On Wed, Oct 16, 2024 at 03:56:44PM +0800, yong.huang@smartx.com wrote: > > From: Hyman Huang <yong.huang@smartx.com> > > > > When VM is configured with huge memory, the current throttle logic > > doesn't look like to scale, because migration_trigger_throttle() > > is only called for each iteration, so it won't be invoked for a long > > time if one iteration can take a long time. > > > > The periodic dirty sync aims to fix the above issue by synchronizing > > the ramblock from remote dirty bitmap and, when necessary, triggering > > the CPU throttle multiple times during a long iteration. > > > > This is a trade-off between synchronization overhead and CPU throttle > > impact. > > > > Signed-off-by: Hyman Huang <yong.huang@smartx.com> > > --- > > migration/cpu-throttle.c | 70 +++++++++++++++++++++++++++++++++++++++- > > migration/cpu-throttle.h | 14 ++++++++ > > migration/migration.h | 1 + > > migration/ram.c | 9 ++++-- > > migration/trace-events | 1 + > > 5 files changed, 92 insertions(+), 3 deletions(-) > > > > diff --git a/migration/cpu-throttle.c b/migration/cpu-throttle.c > > index fa47ee2e21..784b51ab35 100644 > > --- a/migration/cpu-throttle.c > > +++ b/migration/cpu-throttle.c > > @@ -28,16 +28,23 @@ > > #include "qemu/main-loop.h" > > #include "sysemu/cpus.h" > > #include "cpu-throttle.h" > > +#include "migration.h" > > +#include "migration-stats.h" > > +#include "options.h" > > #include "trace.h" > > > > /* vcpu throttling controls */ > > -static QEMUTimer *throttle_timer; > > +static QEMUTimer *throttle_timer, *throttle_dirty_sync_timer; > > static unsigned int throttle_percentage; > > +static bool throttle_dirty_sync_timer_active; > > > > #define CPU_THROTTLE_PCT_MIN 1 > > #define CPU_THROTTLE_PCT_MAX 99 > > #define CPU_THROTTLE_TIMESLICE_NS 10000000 > > > > +/* RAMBlock dirty sync trigger every five seconds */ > > Maybe enrich it to say "making sure it is synchronized every five seconds"? > Because it can synchronize faster if each iteration runs faster than 5sec, > so just to emphasize it's a fallback sync, and only with auto converge. > Agree, I'll refine the comment in the next version. > > > +#define CPU_THROTTLE_DIRTY_SYNC_TIMESLICE_MS 5000 > > + > > static void cpu_throttle_thread(CPUState *cpu, run_on_cpu_data opaque) > > { > > double pct; > > @@ -112,6 +119,7 @@ void cpu_throttle_set(int new_throttle_pct) > > void cpu_throttle_stop(void) > > { > > qatomic_set(&throttle_percentage, 0); > > + cpu_throttle_dirty_sync_timer(false); > > } > > > > bool cpu_throttle_active(void) > > @@ -124,8 +132,68 @@ int cpu_throttle_get_percentage(void) > > return qatomic_read(&throttle_percentage); > > } > > > > +void cpu_throttle_dirty_sync_timer_tick(void *opaque) > > +{ > > + static uint64_t prev_sync_cnt = 2; > > IIUC the hard coded "2" isn't needed, as long as it's guaranteed to be > updated for each timer call, and you special cased "1" anyway below. > Ok. > > > + uint64_t sync_cnt = stat64_get(&mig_stats.dirty_sync_count); > > + > > + if (!migrate_auto_converge()) { > > + /* Stop the timer when auto converge is disabled */ > > + return; > > I think we can try to make sure this never starts if !auto-converge, so > assuming this path will never trigger in real life. > Indeed, this makes the code cleaner. > > + } > > + > > + /* > > + * The first iteration copies all memory anyhow and has no > > + * effect on guest performance, therefore omit it to avoid > > + * paying extra for the sync penalty. > > + */ > > + if (sync_cnt <= 1) { > > + goto end; > > + } > > + > > + if (sync_cnt == prev_sync_cnt) { > > + trace_cpu_throttle_dirty_sync(); > > + WITH_RCU_READ_LOCK_GUARD() { > > + migration_bitmap_sync_precopy(false); > > + } > > + } > > + > > +end: > > + prev_sync_cnt = stat64_get(&mig_stats.dirty_sync_count); > > + > > + timer_mod(throttle_dirty_sync_timer, > > + qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL_RT) + > > + CPU_THROTTLE_DIRTY_SYNC_TIMESLICE_MS); > > +} > > + > > +static bool cpu_throttle_dirty_sync_active(void) > > +{ > > + return qatomic_read(&throttle_dirty_sync_timer_active); > > +} > > + > > +void cpu_throttle_dirty_sync_timer(bool enable) > > +{ > > + if (enable) { > > + assert(throttle_dirty_sync_timer); > > + if (!cpu_throttle_dirty_sync_active()) { > > I suppose this can be logically racy? As I think after this patch this path > can be invoked both in main thread and migration thread. > Indeed, thanks for pointing this out. > > The simplest way to do is to move cpu_throttle_stop() call to be under > bql_lock(), so that this will be serialized by BQL. Then we can add an > assertion at the entry of the function for bql_locked(). > > + timer_mod(throttle_dirty_sync_timer, > > + qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL_RT) + > > + CPU_THROTTLE_DIRTY_SYNC_TIMESLICE_MS); > > + qatomic_set(&throttle_dirty_sync_timer_active, 1); > > + } > > + } else { > > + if (throttle_dirty_sync_timer != NULL) { > > IIUC throttle_dirty_sync_timer is never destroyed, aka, timer_del() only > disables it. So you should probably use throttle_dirty_sync_timer_active? > > > + timer_del(throttle_dirty_sync_timer); > > + qatomic_set(&throttle_dirty_sync_timer_active, 0); > > + } > > + } > > +} > > + > > void cpu_throttle_init(void) > > { > > throttle_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL_RT, > > cpu_throttle_timer_tick, NULL); > > + throttle_dirty_sync_timer = > > + timer_new_ms(QEMU_CLOCK_VIRTUAL_RT, > > + cpu_throttle_dirty_sync_timer_tick, NULL); > > } > > diff --git a/migration/cpu-throttle.h b/migration/cpu-throttle.h > > index d65bdef6d0..420702b8d3 100644 > > --- a/migration/cpu-throttle.h > > +++ b/migration/cpu-throttle.h > > @@ -65,4 +65,18 @@ bool cpu_throttle_active(void); > > */ > > int cpu_throttle_get_percentage(void); > > > > +/** > > + * cpu_throttle_dirty_sync_timer_tick: > > + * > > + * Dirty sync timer hook. > > + */ > > +void cpu_throttle_dirty_sync_timer_tick(void *opaque); > > + > > +/** > > + * cpu_throttle_dirty_sync_timer: > > + * > > + * Start or stop the dirty sync timer. > > + */ > > +void cpu_throttle_dirty_sync_timer(bool enable); > > + > > #endif /* SYSEMU_CPU_THROTTLE_H */ > > diff --git a/migration/migration.h b/migration/migration.h > > index 38aa1402d5..fbd0d19092 100644 > > --- a/migration/migration.h > > +++ b/migration/migration.h > > @@ -537,4 +537,5 @@ int migration_rp_wait(MigrationState *s); > > */ > > void migration_rp_kick(MigrationState *s); > > > > +void migration_bitmap_sync_precopy(bool last_stage); > > #endif > > diff --git a/migration/ram.c b/migration/ram.c > > index 9b5b350405..ac34e731e2 100644 > > --- a/migration/ram.c > > +++ b/migration/ram.c > > @@ -1020,6 +1020,11 @@ static void migration_trigger_throttle(RAMState > *rs) > > migration_transferred_bytes() - rs->bytes_xfer_prev; > > uint64_t bytes_dirty_period = rs->num_dirty_pages_period * > TARGET_PAGE_SIZE; > > uint64_t bytes_dirty_threshold = bytes_xfer_period * threshold / > 100; > > + bool auto_converge = migrate_auto_converge(); > > + > > + if (auto_converge) { > > + cpu_throttle_dirty_sync_timer(true); > > + } > > If you have the guard to skip the 1st sync in the timer fn(), IIUC you can > move this earlier to e.g. migration_thread() before iteration starts. > Otherwise it'll be not as clear on when this timer will start if it hides > in the sync path itself. > > > > > /* > > * The following detection logic can be refined later. For now: > > @@ -1031,7 +1036,7 @@ static void migration_trigger_throttle(RAMState > *rs) > > if ((bytes_dirty_period > bytes_dirty_threshold) && > > (++rs->dirty_rate_high_cnt >= 2)) { > > rs->dirty_rate_high_cnt = 0; > > - if (migrate_auto_converge()) { > > + if (auto_converge) { > > trace_migration_throttle(); > > mig_throttle_guest_down(bytes_dirty_period, > > bytes_dirty_threshold); > > @@ -1088,7 +1093,7 @@ static void migration_bitmap_sync(RAMState *rs, > bool last_stage) > > } > > } > > > > -static void migration_bitmap_sync_precopy(bool last_stage) > > +void migration_bitmap_sync_precopy(bool last_stage) > > { > > Error *local_err = NULL; > > assert(ram_state); > > diff --git a/migration/trace-events b/migration/trace-events > > index 9a19599804..0638183056 100644 > > --- a/migration/trace-events > > +++ b/migration/trace-events > > @@ -381,3 +381,4 @@ migration_pagecache_insert(void) "Error allocating > page" > > > > # cpu-throttle.c > > cpu_throttle_set(int new_throttle_pct) "set guest CPU throttled by > %d%%" > > +cpu_throttle_dirty_sync(void) "" > > -- > > 2.27.0 > > > > -- > Peter Xu > > All the comments above are advisable, thanks Peter, I'll try it in the next version. Yong
diff --git a/migration/cpu-throttle.c b/migration/cpu-throttle.c index fa47ee2e21..784b51ab35 100644 --- a/migration/cpu-throttle.c +++ b/migration/cpu-throttle.c @@ -28,16 +28,23 @@ #include "qemu/main-loop.h" #include "sysemu/cpus.h" #include "cpu-throttle.h" +#include "migration.h" +#include "migration-stats.h" +#include "options.h" #include "trace.h" /* vcpu throttling controls */ -static QEMUTimer *throttle_timer; +static QEMUTimer *throttle_timer, *throttle_dirty_sync_timer; static unsigned int throttle_percentage; +static bool throttle_dirty_sync_timer_active; #define CPU_THROTTLE_PCT_MIN 1 #define CPU_THROTTLE_PCT_MAX 99 #define CPU_THROTTLE_TIMESLICE_NS 10000000 +/* RAMBlock dirty sync trigger every five seconds */ +#define CPU_THROTTLE_DIRTY_SYNC_TIMESLICE_MS 5000 + static void cpu_throttle_thread(CPUState *cpu, run_on_cpu_data opaque) { double pct; @@ -112,6 +119,7 @@ void cpu_throttle_set(int new_throttle_pct) void cpu_throttle_stop(void) { qatomic_set(&throttle_percentage, 0); + cpu_throttle_dirty_sync_timer(false); } bool cpu_throttle_active(void) @@ -124,8 +132,68 @@ int cpu_throttle_get_percentage(void) return qatomic_read(&throttle_percentage); } +void cpu_throttle_dirty_sync_timer_tick(void *opaque) +{ + static uint64_t prev_sync_cnt = 2; + uint64_t sync_cnt = stat64_get(&mig_stats.dirty_sync_count); + + if (!migrate_auto_converge()) { + /* Stop the timer when auto converge is disabled */ + return; + } + + /* + * The first iteration copies all memory anyhow and has no + * effect on guest performance, therefore omit it to avoid + * paying extra for the sync penalty. + */ + if (sync_cnt <= 1) { + goto end; + } + + if (sync_cnt == prev_sync_cnt) { + trace_cpu_throttle_dirty_sync(); + WITH_RCU_READ_LOCK_GUARD() { + migration_bitmap_sync_precopy(false); + } + } + +end: + prev_sync_cnt = stat64_get(&mig_stats.dirty_sync_count); + + timer_mod(throttle_dirty_sync_timer, + qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL_RT) + + CPU_THROTTLE_DIRTY_SYNC_TIMESLICE_MS); +} + +static bool cpu_throttle_dirty_sync_active(void) +{ + return qatomic_read(&throttle_dirty_sync_timer_active); +} + +void cpu_throttle_dirty_sync_timer(bool enable) +{ + if (enable) { + assert(throttle_dirty_sync_timer); + if (!cpu_throttle_dirty_sync_active()) { + timer_mod(throttle_dirty_sync_timer, + qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL_RT) + + CPU_THROTTLE_DIRTY_SYNC_TIMESLICE_MS); + qatomic_set(&throttle_dirty_sync_timer_active, 1); + } + } else { + if (throttle_dirty_sync_timer != NULL) { + timer_del(throttle_dirty_sync_timer); + qatomic_set(&throttle_dirty_sync_timer_active, 0); + } + } +} + void cpu_throttle_init(void) { throttle_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL_RT, cpu_throttle_timer_tick, NULL); + throttle_dirty_sync_timer = + timer_new_ms(QEMU_CLOCK_VIRTUAL_RT, + cpu_throttle_dirty_sync_timer_tick, NULL); } diff --git a/migration/cpu-throttle.h b/migration/cpu-throttle.h index d65bdef6d0..420702b8d3 100644 --- a/migration/cpu-throttle.h +++ b/migration/cpu-throttle.h @@ -65,4 +65,18 @@ bool cpu_throttle_active(void); */ int cpu_throttle_get_percentage(void); +/** + * cpu_throttle_dirty_sync_timer_tick: + * + * Dirty sync timer hook. + */ +void cpu_throttle_dirty_sync_timer_tick(void *opaque); + +/** + * cpu_throttle_dirty_sync_timer: + * + * Start or stop the dirty sync timer. + */ +void cpu_throttle_dirty_sync_timer(bool enable); + #endif /* SYSEMU_CPU_THROTTLE_H */ diff --git a/migration/migration.h b/migration/migration.h index 38aa1402d5..fbd0d19092 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -537,4 +537,5 @@ int migration_rp_wait(MigrationState *s); */ void migration_rp_kick(MigrationState *s); +void migration_bitmap_sync_precopy(bool last_stage); #endif diff --git a/migration/ram.c b/migration/ram.c index 9b5b350405..ac34e731e2 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1020,6 +1020,11 @@ static void migration_trigger_throttle(RAMState *rs) migration_transferred_bytes() - rs->bytes_xfer_prev; uint64_t bytes_dirty_period = rs->num_dirty_pages_period * TARGET_PAGE_SIZE; uint64_t bytes_dirty_threshold = bytes_xfer_period * threshold / 100; + bool auto_converge = migrate_auto_converge(); + + if (auto_converge) { + cpu_throttle_dirty_sync_timer(true); + } /* * The following detection logic can be refined later. For now: @@ -1031,7 +1036,7 @@ static void migration_trigger_throttle(RAMState *rs) if ((bytes_dirty_period > bytes_dirty_threshold) && (++rs->dirty_rate_high_cnt >= 2)) { rs->dirty_rate_high_cnt = 0; - if (migrate_auto_converge()) { + if (auto_converge) { trace_migration_throttle(); mig_throttle_guest_down(bytes_dirty_period, bytes_dirty_threshold); @@ -1088,7 +1093,7 @@ static void migration_bitmap_sync(RAMState *rs, bool last_stage) } } -static void migration_bitmap_sync_precopy(bool last_stage) +void migration_bitmap_sync_precopy(bool last_stage) { Error *local_err = NULL; assert(ram_state); diff --git a/migration/trace-events b/migration/trace-events index 9a19599804..0638183056 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -381,3 +381,4 @@ migration_pagecache_insert(void) "Error allocating page" # cpu-throttle.c cpu_throttle_set(int new_throttle_pct) "set guest CPU throttled by %d%%" +cpu_throttle_dirty_sync(void) ""