Commit 05c0a9de authored by He Zhenxing's avatar He Zhenxing
Browse files

BUG#35843 Slow replication slave when using partitioned myisam table 

      
In order to improve the performance when replicating to partitioned
myisam tables with row-based format, the number of rows of current 
rows log event is estimated and used to setup storage engine for bulk
inserts.
parent 7388a9f5

sql/log_event.cc

+10 −2
Original line number Diff line number Diff line
@@ -8061,7 +8061,6 @@ Write_rows_log_event::do_before_row_operations(const Slave_reporting_capability 
    */

  }



  m_table->file->ha_start_bulk_insert(0);

  /*

    We need TIMESTAMP_NO_AUTO_SET otherwise ha_write_row() will not use fill

    any TIMESTAMP column with data from the row but instead will use
@@ -8200,6 +8199,15 @@ Rows_log_event::write_row(const Relay_log_info *const rli, 
  

  /* unpack row into table->record[0] */

  error= unpack_current_row(rli); // TODO: how to handle errors?

  if (m_curr_row == m_rows_buf)

  {

    /* this is the first row to be inserted, we estimate the rows with

       the size of the first row and use that value to initialize

       storage engine for bulk insertion */

    ulong estimated_rows= (m_rows_end - m_curr_row) / (m_curr_row_end - m_curr_row);

    m_table->file->ha_start_bulk_insert(estimated_rows);

  }

  

  

#ifndef DBUG_OFF

  DBUG_DUMP("record[0]", table->record[0], table->s->reclength);