diff options
Diffstat (limited to 'Docs/manual.texi')
| -rw-r--r-- | Docs/manual.texi | 127 |
1 files changed, 73 insertions, 54 deletions
diff --git a/Docs/manual.texi b/Docs/manual.texi index df903a22191..7d873447928 100644 --- a/Docs/manual.texi +++ b/Docs/manual.texi @@ -20285,59 +20285,64 @@ The following columns are returned: below, though the format and numbers probably differ: @example -+--------------------------+------------+ -| Variable_name | Value | -+--------------------------+------------+ -| Aborted_clients | 0 | -| Aborted_connects | 0 | -| Bytes_received | 142160923 | -| Bytes_sent | 1161910370 | -| Connections | 30022 | -| Created_tmp_disk_tables | 0 | -| Created_tmp_tables | 8988 | -| Delayed_insert_threads | 0 | -| Delayed_writes | 0 | -| Delayed_errors | 0 | -| Flush_commands | 1 | -| Handler_delete | 462604 | -| Handler_read_first | 95882 | -| Handler_read_key | 27681068 | -| Handler_read_next | 265008218 | -| Handler_read_prev | 3022500 | -| Handler_read_rnd | 36900998 | -| Handler_read_rnd_next | 252097176 | -| Handler_update | 16945404 | -| Handler_write | 66826676 | -| Key_blocks_used | 14955 | -| Key_read_requests | 90131960 | -| Key_reads | 163268 | -| Key_write_requests | 7573912 | -| Key_writes | 3780151 | -| Max_used_connections | 0 | -| Not_flushed_key_blocks | 0 | -| Not_flushed_delayed_rows | 0 | -| Open_tables | 0 | -| Open_files | 0 | -| Open_streams | 0 | -| Opened_tables | 44598 | -| Questions | 1866024 | -| Select_full_join | 0 | -| Select_full_range_join | 0 | -| Select_range | 68187 | -| Select_range_check | 0 | -| Select_scan | 31440 | -| Slave_running | OFF | -| Slow_launch_threads | 0 | -| Slow_queries | 0 | -| Sort_range | 0 | -| Sort_rows | 36650500 | -| Sort_scan | 5298 | -| Threads_cached | 0 | -| Threads_connected | 1 | -| Threads_created | 30022 | -| Threads_running | 1 | -| Uptime | 39613 | -+--------------------------+------------+ ++--------------------------+--------+ +| Variable_name | Value | ++--------------------------+--------+ +| Aborted_clients | 0 | +| Aborted_connects | 0 | +| Bytes_received | 629539 | +| Bytes_sent | 736394 | +| Connections | 62 | +| Created_tmp_disk_tables | 0 | +| Created_tmp_tables | 0 | +| Created_tmp_files | 0 | +| Delayed_insert_threads | 0 | +| Delayed_writes | 0 | +| Delayed_errors | 0 | +| Flush_commands | 1 | +| Handler_delete | 0 | +| Handler_read_first | 1 | +| Handler_read_key | 9201 | +| Handler_read_next | 0 | +| Handler_read_prev | 0 | +| Handler_read_rnd | 0 | +| Handler_read_rnd_next | 45 | +| Handler_update | 5998 | +| Handler_write | 0 | +| Key_blocks_used | 407 | +| Key_read_requests | 27683 | +| Key_reads | 407 | +| Key_write_requests | 0 | +| Key_writes | 0 | +| Max_used_connections | 60 | +| Not_flushed_key_blocks | 0 | +| Not_flushed_delayed_rows | 0 | +| Open_tables | 60 | +| Open_files | 66 | +| Open_streams | 0 | +| Opened_tables | 66 | +| Questions | 9308 | +| Select_full_join | 0 | +| Select_full_range_join | 0 | +| Select_range | 0 | +| Select_range_check | 0 | +| Select_scan | 0 | +| Slave_running | OFF | +| Slave_open_temp_tables | 0 | +| Slow_launch_threads | 0 | +| Slow_queries | 0 | +| Sort_merge_passes | 0 | +| Sort_range | 0 | +| Sort_rows | 0 | +| Sort_scan | 0 | +| Table_locks_immediate | 3183 | +| Table_locks_waited | 6030 | +| Threads_cached | 30 | +| Threads_created | 61 | +| Threads_connected | 31 | +| Threads_running | 31 | +| Uptime | 135 | ++--------------------------+--------+ @end example @cindex variables, status @@ -20400,6 +20405,12 @@ open by the slave thread @item @code{Sort_range} @tab Number of sorts that where done with ranges. @item @code{Sort_rows} @tab Number of sorted rows. @item @code{Sort_scan} @tab Number of sorts that where done by scanning the table. +@item @code{Table_locks_immediate} @tab Number of times a table lock was +acquired immediately. Available after 3.23.33. +@item @code{Table_locks_waited} @tab Number of times a table lock could not +be acquired immediately and a wait was needed. If this is high, and you +have performance problems, you should first optimize your queries, and then +either split your table(s) or use replication. Available after 3.23.33. @item @code{Threads_cached} @tab Number of threads in the thread cache. @item @code{Threads_connected} @tab Number of currently open connections. @item @code{Threads_created} @tab Number of threads created to handle connections. @@ -40814,6 +40825,9 @@ not yet 100 % confident in this code. @appendixsubsec Changes in release 3.23.33 @itemize bullet @item +Added @code{Table_locks_immediate} and @code{Table_locks_waited} status +variables +@item Fixed bug in replication that broke slave server start with existing @code{master.info}. This fixes a bug introduced in 3.23.32. @item @@ -46638,10 +46652,15 @@ for @code{BDB} tables. @xref{Internal locking}. With @code{MyISAM} tables one can freely mix @code{INSERT} and @code{SELECT} without locks (@code{Versioning}). +Starting in version 3.23.33, you can analyze the table lock contention +on your system by checkining @code{Table_locks_waited} and +@code{Table_locks_immediate} environemt variables. + Some database users claim that @strong{MySQL} cannot support near the number of concurrent users because it lacks row-level locking. This is a may be true for some specific applications, but is' not generally -true. As always this depends totally on what the application does and what is the access/update pattern of the data. +true. As always this depends totally on what the application does and what +is the access/update pattern of the data. Pros for row locking: |