firebird-qa/tests/bugs/gh_6875_test.py

#coding:utf-8
#
# id:           bugs.gh_6875
# title:        Significant performance regression of SIMILAR TO and SUBSTRING(SIMILAR) when pattern is taken from variable (rather than directly specified)
# decription:   
#                   https://github.com/FirebirdSQL/firebird/issues/6875
#               
#                   Confirmed poor performance in 5.0.0.88 (before fix):
#                                              in PSQL    explicitly
#                                              variable   specified
#                                              ----------------------
#                   * for SIMILAR TO:            11.40"         2.23"
#                   * for SUBSTRING...SIMILAR:   42.02"         1.37"
#               
#                   Checked 4.0.1.2523 and 5.0.0.89 -- all OK.
#                   Performance in 5.0.0.89 (intermediate build 02.07.2021 14:43) after fix:
#                                              in PSQL    explicitly
#                                              variable   specified
#                                              ----------------------
#                   * for SIMILAR TO:             1.27"         1.15"
#                   * for SUBSTRING...SIMILAR:    2.02"         2.00"
#               
#                   Performance in 4.0.1.2523 (intermediate build 02.07.2021 18:55) after fix:
#                                              in PSQL    explicitly
#                                              variable   specified
#                                              ----------------------
#                   * for SIMILAR TO:             1.03"         1.06"
#                   * for SUBSTRING...SIMILAR:    1.96"         1.97"
#               
#                   So, values became almost the same and, moreover, performance was greatly improved.
#               
#                   Test checks ratio between elapsed times and compares it with thresholds.
#                   Currently both SIMILAR TO and SUBSTRING...SIMILAR use the same thresholds =  1.30.
#                
# tracker_id:   
# min_versions: ['4.0.1']
# versions:     4.0.1
# qmid:         None

import pytest
from firebird.qa import db_factory, isql_act, Action

# version: 4.0.1
# resources: None

substitutions_1 = []

init_script_1 = """"""

db_1 = db_factory(sql_dialect=3, init=init_script_1)

test_script_1 = """
    set bail on;
    set list on;
    set term ^;
    create or alter procedure sp_similar_to_test (
        N integer,
        V integer)
    as
        declare nums varchar(16) = '[-+]?[0-9]{1,10}';
        declare b boolean;
    begin
      while (n > 0) do
      begin
        if (v = 1) then
          b = '5' similar to nums; -------------------- [ 1 ]
        else if (v = 2) then
          b = '5' similar to '[-+]?[0-9]{1,10}'; ------ [ 2 ]
        n = n - 1;
      end
    end
    ^
    create or alter procedure sp_substring_similar_test (
        N integer,
        V integer)
    as
        declare p varchar(100) = '%/#*(=){3,}#"%#"(=){3,}#*/%';
        declare s varchar(1000);
    begin
      while (n > 0) do
      begin
        if (v = 1) then
          s = substring('
                            aaa
                            /*==== comment between "equal" characters ====*/
                            bbb
                            ccc
                            ddd
                            eee
                            fff
                            jjj
    	                ' similar p escape '#');

        else if (v = 2) then
          s = substring('
                            aaa
                            /*==== comment between "equal" characters  ====*/
                            bbb
                            ccc
                            ddd
                            eee
                            fff
                            jjj
    	                ' similar '%/#*(=){3,}#"%#"(=){3,}#*/%' escape '#');

        n = n - 1;
      end
    end
    ^
    commit
    ^
    execute block returns(msg_similar2 varchar(255), msg_subs_sim varchar(255)) as
        declare t0_similar_to timestamp;
        declare t0_subs_simil timestamp;
        declare elap_similar2_pattern_in_psql_var int;
        declare elap_similar2_pattern_explicitly int;
        declare elap_subs_sim_pattern_in_psql_var int;
        declare elap_subs_sim_pattern_explicitly int;

        -- ##############################
        -- ###   T H R E S H O L D S  ###
        -- ##############################
        declare SIMILAR2_THRESHOLD double precision = 1.30;
        declare SUBS_SIM_THRESHOLD double precision = 1.30;

    begin
        t0_similar_to = 'now';
        execute procedure sp_similar_to_test(1000000, 1);
        elap_similar2_pattern_in_psql_var = datediff(millisecond from t0_similar_to to  cast('now' as timestamp));

        -- rdb$set_context('USER_SESSION', 'SIMILAR2_PATTERN_DECLARED_IN_PSQL_VAR', datediff(millisecond from t0_similar_to to  cast('now' as timestamp)));

        t0_similar_to = 'now';
        execute procedure sp_similar_to_test(1000000, 2);
        elap_similar2_pattern_explicitly = datediff(millisecond from t0_similar_to to  cast('now' as timestamp));

        -- rdb$set_context('USER_SESSION', 'SIMILAR2_PATTERN_EXPLICITLY_SPECIFIED', datediff(millisecond from t0_similar_to to  cast('now' as timestamp)));

        t0_subs_simil = 'now';
        execute procedure sp_substring_similar_test(100000, 1);
        elap_subs_sim_pattern_in_psql_var = datediff(millisecond from t0_subs_simil to  cast('now' as timestamp));

        --rdb$set_context('USER_SESSION', 'SUBS_SIM_PATTERN_DECLARED_IN_PSQL_VAR', datediff(millisecond from t0_subs_simil to  cast('now' as timestamp)));

        t0_subs_simil = 'now';
        execute procedure sp_substring_similar_test(100000, 2);
        elap_subs_sim_pattern_explicitly = datediff(millisecond from t0_subs_simil to  cast('now' as timestamp));
        -- rdb$set_context('USER_SESSION', 'SUBS_SIM_PATTERN_EXPLICITLY_SPECIFIED', datediff(millisecond from t0_subs_simil to  cast('now' as timestamp)));

        if ( 1.00 * elap_similar2_pattern_in_psql_var / elap_similar2_pattern_explicitly > SIMILAR2_THRESHOLD ) then
            msg_similar2 = 'INACCEPTABLE: '
                           || elap_similar2_pattern_in_psql_var
                           || 's  == vs ==  ' 
                           || elap_similar2_pattern_explicitly || 's' 
                           || ' -  greater than treshold = ' || SIMILAR2_THRESHOLD
            ;
        else
            msg_similar2 = 'Acceptable.';


        if ( 1.00 * elap_subs_sim_pattern_in_psql_var / elap_subs_sim_pattern_explicitly > SUBS_SIM_THRESHOLD ) then
            msg_subs_sim = 'INACCEPTABLE: '
                           || elap_subs_sim_pattern_in_psql_var
                           || 'ms  == vs ==  ' 
                           || elap_subs_sim_pattern_explicitly || 'ms' 
                           || ' -  greater than treshold = ' || SIMILAR2_THRESHOLD
            ;
        else
            msg_subs_sim = 'Acceptable.';

        
        suspend;

    end
    ^
    set term ;^
    commit;

"""

act_1 = isql_act('db_1', test_script_1, substitutions=substitutions_1)

expected_stdout_1 = """
    MSG_SIMILAR2                    Acceptable.
    MSG_SUBS_SIM                    Acceptable.
"""

@pytest.mark.version('>=4.0.1')
def test_1(act_1: Action):
    act_1.expected_stdout = expected_stdout_1
    act_1.execute()
    assert act_1.clean_stdout == act_1.clean_expected_stdout