Initialize abs_timeout when it is about to be used. This saves one my_hrtime()
call on hot path (when we acquire MDL lock without waiting).
When filling I_S.PROCESSLIST use THD::start_utime/THD::utime_after_query instead
of THD::start_time. This allows us to save 2 clock_gettime() calls.
Overhead change:
__clock_gettime 0.13% -> 0.11% (122 -> 76 calls per OLTP RO transaction)
my_interval_timer 0.07% -> 0.06%
my_hrtime 0.04% -> 0.01%
THD::enter_stage() optimizations:
- stage backup code moved to THD::backup_stage(), saves one condition
- moved check for "new_stage" out to callers that actually need it
- remnants of enter_stage() moved to sql_class.h so it can be inlined
THD::enter_stage() overhead dropped 0.48% -> 0.07%.
PROFILING::status_change() optimizations:
- "status_arg" is now checked by QUERY_PROFILE::new_status()
- no need to check "enabled": !enabled && current is impossible
- remnants of status_change() moved to sql_profile.h so it can be inlined
PROFILING::status_change() overhead dropped 0.1% -> out of radar.
The bug was that open_tables() returned error in case of
thd->killed() without properly calling thd->send_kill_message()
to set the correct error. This was fixed already in get_schema_column_record,
so the code was just copied to get_geometry_column_record.
Description: On an example MySQL instance with 28k empty
InnoDB tables, a specific query to information_schema.tables
and information_schema.columns leads to memory consumption
over 38GB RSS.
Analysis: In get_all_tables() call, we fill the I_S tables
from frm files and storage engine. As part of that process
we call make_table_name_list() and allocate memory for all
the 28k frm file names in the THD mem_root through
make_lex_string_root(). Since it has been called around
28k * 28k times there is a huge memory getting hogged in
THD mem_root. This causes the RSS to grow to 38GB.
Fix: As part of fix we are creating a temporary mem_root
in get_all_tables and passing it to fill_fiels(). There we
replace the THD mem_root with the temporary mem_root and
allocates the file names in temporary mem_root and frees
it once we fill the I_S tables in get_all_tables and
re-assign the original mem_root back to THD mem_root.
Note: Checked the massif out put with the fix now the memory growth is just around 580MB at peak.
BINLOGGED INCORRECTLY - BREAKS A SLAVE
Submitted a incomplete patch with my previous push,
re submitting the extra changes the required to make
the patch complete.
Stage "Filling schema table" is now properly shown in 'show processlist'
mysys/mf_keycache.c:
Simple cleanup with more comments
sql/lock.cc:
Return to original stage after mysql_lock_tables
Made 'Table lock' as a true stage
sql/sql_show.cc:
Restore original stage after get_schema_tables_result
The GEOMETRY field metadata is stored in the FRM file.
SRID for a spatial column now can be stored, it was added to the CREATE TABLE syntax,
so the AddGeometryData() stored procedure is now possible. Script adding the required Add/DropGeometryColumn sp-s added.
The real bug was that open_tables() returned error in case of
thd->killed() without properly calling thd->send_kill_message()
to set the correct error. This was fixed some time ago.
So remove the, now redundant, extra checks for thd->is_error(),
possibly allowing to catch in debug builds more incorrect
error handling cases.
Extend existing plugins to support
* SHOW QUERY_RESPONSE_TIME
* FLUSH QUERY_RESPONSE_TIME
* SHOW LOCALE
move userstat tables to use the new API instead of
hand-coded syntax
