* Keqian Zhu (zhukeqi...@huawei.com) wrote: > real_dirty_pages becomes equal to total ram size after dirty log sync > in ram_init_bitmaps, the reason is that the bitmap of ramblock is > initialized to be all set, so old path counts them as "real dirty" at > beginning. > > This causes wrong dirty rate and false positive throttling. > > Signed-off-by: Keqian Zhu <zhukeqi...@huawei.com>
OK, Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com> and queued. you might still want to look at migration_trigger_thrtottle and see if you can stop the throttling if in the RAM bulk stage. > --- > Changelog: > > v3: > - Address Dave's comments. > > v2: > - Use new_dirty_pages instead of accu_dirty_pages. > - Adjust commit messages. > --- > include/exec/ram_addr.h | 5 +---- > migration/ram.c | 8 +++++--- > 2 files changed, 6 insertions(+), 7 deletions(-) > > diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h > index 7b5c24e928..3ef729a23c 100644 > --- a/include/exec/ram_addr.h > +++ b/include/exec/ram_addr.h > @@ -442,8 +442,7 @@ static inline void > cpu_physical_memory_clear_dirty_range(ram_addr_t start, > static inline > uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock *rb, > ram_addr_t start, > - ram_addr_t length, > - uint64_t *real_dirty_pages) > + ram_addr_t length) > { > ram_addr_t addr; > unsigned long word = BIT_WORD((start + rb->offset) >> TARGET_PAGE_BITS); > @@ -469,7 +468,6 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock > *rb, > if (src[idx][offset]) { > unsigned long bits = atomic_xchg(&src[idx][offset], 0); > unsigned long new_dirty; > - *real_dirty_pages += ctpopl(bits); > new_dirty = ~dest[k]; > dest[k] |= bits; > new_dirty &= bits; > @@ -502,7 +500,6 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(RAMBlock > *rb, > start + addr + offset, > TARGET_PAGE_SIZE, > DIRTY_MEMORY_MIGRATION)) { > - *real_dirty_pages += 1; > long k = (start + addr) >> TARGET_PAGE_BITS; > if (!test_and_set_bit(k, dest)) { > num_dirty++; > diff --git a/migration/ram.c b/migration/ram.c > index 069b6e30bc..5554a7d2d8 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -859,9 +859,11 @@ static inline bool migration_bitmap_clear_dirty(RAMState > *rs, > /* Called with RCU critical section */ > static void ramblock_sync_dirty_bitmap(RAMState *rs, RAMBlock *rb) > { > - rs->migration_dirty_pages += > - cpu_physical_memory_sync_dirty_bitmap(rb, 0, rb->used_length, > - &rs->num_dirty_pages_period); > + uint64_t new_dirty_pages = > + cpu_physical_memory_sync_dirty_bitmap(rb, 0, rb->used_length); > + > + rs->migration_dirty_pages += new_dirty_pages; > + rs->num_dirty_pages_period += new_dirty_pages; > } > > /** > -- > 2.19.1 > > -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK