Commit 13bee852 authored by unknown's avatar unknown
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BUG#26286 (row-based logging scales worse than statement-based logging): 

Submitting patch on Guilhem's behalf (he found the solution).
  
Correcting a typo that caused very big increases in memory usage when
more memory needed to be allocated for row-based events. Also correcting
a border case check when more memory needed to be allocated.


sql/log_event.cc:
  Correcting typo that caused very big increases in memory allocation.
  Correcting border case for when more memory should be allocated.
parent f6034619

sql/log_event.cc

+3 −3
Original line number Diff line number Diff line
@@ -5515,13 +5515,13 @@ int Rows_log_event::do_add_row_data(byte *const row_data, 
  DBUG_ASSERT(m_rows_cur <= m_rows_end);



  /* The cast will always work since m_rows_cur <= m_rows_end */

  if (static_cast<my_size_t>(m_rows_end - m_rows_cur) < length)

  if (static_cast<my_size_t>(m_rows_end - m_rows_cur) <= length)

  {

    my_size_t const block_size= 1024;

    my_ptrdiff_t const old_alloc= m_rows_end - m_rows_buf;

    my_ptrdiff_t const cur_size= m_rows_cur - m_rows_buf;

    my_ptrdiff_t const new_alloc= 

        block_size * ((cur_size + length) / block_size + block_size - 1);

        block_size * ((cur_size + length + block_size - 1) / block_size);



    byte* const new_buf= (byte*)my_realloc((gptr)m_rows_buf, new_alloc,

                                           MYF(MY_ALLOW_ZERO_PTR|MY_WME));
@@ -5542,7 +5542,7 @@ int Rows_log_event::do_add_row_data(byte *const row_data, 
    m_rows_end= m_rows_buf + new_alloc;

  }



  DBUG_ASSERT(m_rows_cur + length < m_rows_end);

  DBUG_ASSERT(m_rows_cur + length <= m_rows_end);

  memcpy(m_rows_cur, row_data, length);

  m_rows_cur+= length;

  m_row_count++;