@item @code{Open_files} @tab Number of files that are open.
@item @code{Open_streams} @tab Number of streams that are open (used mainly for logging).
@item @code{Opened_tables} @tab Number of tables that have been opened.
@item @code{Select_full_join} @tab Number of joins without keys (Should be 0).
@item @code{Select_full_join} @tab Number of joins without keys (If this is 0, you should carefully check the index of your tables).
@item @code{Select_full_range_join} @tab Number of joins where we used a range search on reference table.
@item @code{Select_range} @tab Number of joins where we used ranges on the first table. (It's normally not critical even if this is big.)
@item @code{Select_scan} @tab Number of joins where we scanned the first table.
@item @code{Select_range_check} @tab Number of joins without keys where we check for key usage after each row (Should be 0).
@item @code{Select_scan} @tab Number of joins where we did a full scann of the first table.
@item @code{Select_range_check} @tab Number of joins without keys where we check for key usage after each row (If this is 0, you should carefully check the index of your tables).
@item @code{Questions} @tab Number of queries sent to the server.
@item @code{Slave_open_temp_tables} @tab Number of temporary tables currently
open by the slave thread
@item @code{Slow_launch_threads} @tab Number of threads that have taken more than @code{slow_launch_time} to connect.
@item @code{Slow_launch_threads} @tab Number of threads that have taken more than @code{slow_launch_time} to create.
@item @code{Slow_queries} @tab Number of queries that have taken more than @code{long_query_time}. @xref{Slow query log}.
@item @code{Sort_merge_passes} @tab Number of merges the sort has to do. If this value is large you should consider increasing @code{sort_buffer}.
@item @code{Sort_merge_passes} @tab Number of merges passes the sort algoritm have had to do. If this value is large you should consider increasing @code{sort_buffer}.
@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.
...
...
@@ -19712,8 +19712,8 @@ Some comments about the above:
If @code{Opened_tables} is big, then your @code{table_cache}
variable is probably too small.
@item
If @code{key_reads} is big, then your @code{key_cache} is probably too
small. The cache hit rate can be calculated with
If @code{key_reads} is big, then your @code{key_buffer_size} variable is
probably too small. The cache hit rate can be calculated with
@code{key_reads}/@code{key_read_requests}.
@item
If @code{Handler_read_rnd} is big, then you probably have a lot of
...
...
@@ -46916,6 +46916,15 @@ not yet 100% confident in this code.
@appendixsubsec Changes in release 3.23.51
@itemize @bullet
@item
Changed name of variables @code{Com_show_master_stat} to
@code{Com_show_master_status} and @code{Com_show_slave_stat} to
@code{Com_show_slave_status}.
@item
Changed handling of @code{gethostbyname()} to make the client library
threadsafe even if @code{gethostbyname_r} doesn't exists.
@item
Fixed core-dump problem when giving a wrong password string to @code{GRANT}.
@item
Fixed bug in @code{DROP DATABASE} with symlinked directory.
@item
Fixed optimization problem with @code{DATETIME} and value outside
