Re: [PATCH v5 04/12] migration/dirtyrate: Add dirtyrate statistics series functions

[Zheng Chuan]

On 2020/8/26 20:09, Dr. David Alan Gilbert wrote:
> * Chuan Zheng (zhengchuan@huawei.com) wrote:
>> Add dirtyrate statistics to record/update dirtyrate info.
>>
>> Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>
>> ---
>>  migration/dirtyrate.c | 29 +++++++++++++++++++++++++++++
>>  migration/dirtyrate.h | 10 ++++++++++
>>  2 files changed, 39 insertions(+)
>>
>> diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
>> index 91987c5..0d7163f 100644
>> --- a/migration/dirtyrate.c
>> +++ b/migration/dirtyrate.c
>> @@ -24,6 +24,7 @@
>>  #include "dirtyrate.h"
>>  
>>  static int CalculatingState = DIRTY_RATE_STATUS_UNSTARTED;
>> +static struct DirtyRateStat DirtyStat;
>>  
>>  static int dirtyrate_set_state(int *state, int old_state, int new_state)
>>  {
>> @@ -35,6 +36,34 @@ static int dirtyrate_set_state(int *state, int old_state, 
>> int new_state)
>>      }
>>  }
>>  
>> +static void reset_dirtyrate_stat(void)
>> +{
>> +    DirtyStat.total_dirty_samples = 0;
>> +    DirtyStat.total_sample_count = 0;
>> +    DirtyStat.total_block_mem_MB = 0;
>> +    DirtyStat.dirty_rate = 0;
>> +}
>> +
>> +static void update_dirtyrate_stat(struct RamblockDirtyInfo *info)
>> +{
>> +    DirtyStat.total_dirty_samples += info->sample_dirty_count;
>> +    DirtyStat.total_sample_count += info->sample_pages_count;
>> +    /* size of 4K pages in MB */
>> +    DirtyStat.total_block_mem_MB += info->ramblock_pages / 256;
> 
> You need to be consistent with your use of constants, you have
> a DIRTYRATE_SAMPLE_PAGE_SIZE in a later patch; so use it rather than
> hard coding 256 here.
> 
> Dave
> 
Sure.
I may take as
'DirtyStat.total_block_mem_MB += (info->ramblock_pages * 
DIRTYRATE_SAMPLE_PAGE_SIZE) >> 20';

>> +}
>> +
>> +static void update_dirtyrate(uint64_t msec)
>> +{
>> +    uint64_t dirtyrate;
>> +    uint64_t total_dirty_samples = DirtyStat.total_dirty_samples;
>> +    uint64_t total_sample_count = DirtyStat.total_sample_count;
>> +    uint64_t total_block_mem_MB = DirtyStat.total_block_mem_MB;
>> +
>> +    dirtyrate = total_dirty_samples * total_block_mem_MB *
>> +                 1000 / (total_sample_count * msec);
>> +
>> +    DirtyStat.dirty_rate = dirtyrate;
>> +}
>>  
>>  static void calculate_dirtyrate(struct DirtyRateConfig config)
>>  {
>> diff --git a/migration/dirtyrate.h b/migration/dirtyrate.h
>> index dc45419..8e25d93 100644
>> --- a/migration/dirtyrate.h
>> +++ b/migration/dirtyrate.h
>> @@ -45,6 +45,16 @@ struct RamblockDirtyInfo {
>>      uint32_t *hash_result; /* array of hash result for sampled pages */
>>  };
>>  
>> +/*
>> + * Store calculation statistics for each measure.
>> + */
>> +struct DirtyRateStat {
>> +    uint64_t total_dirty_samples; /* total dirty sampled page */
>> +    uint64_t total_sample_count; /* total sampled pages */
>> +    uint64_t total_block_mem_MB; /* size of total sampled pages in MB */
>> +    int64_t dirty_rate; /* dirty rate in MB/s */
>> +};
>> +
>>  void *get_dirtyrate_thread(void *arg);
>>  #endif
>>  
>> -- 
>> 1.8.3.1
>>