diff --git a/tests/bugs/gh_7759_test.py b/tests/bugs/gh_7759_test.py
new file mode 100644
index 00000000..08ff6e62
--- /dev/null
+++ b/tests/bugs/gh_7759_test.py
@@ -0,0 +1,216 @@
+#coding:utf-8
+
+"""
+ID:          issue-7759
+ISSUE:       https://github.com/FirebirdSQL/firebird/issues/7759
+TITLE:       Routine calling overhead increased by factor 6
+DESCRIPTION:
+    Test creates standalone function and procedure ('sa_func', 'sa_proc').
+    Also, package 'pg_test' with similar function and procedure is created ('pg_func', 'pg_proc').
+    Every of these units is called from appropriate procedures which accept input argument for number
+    of iterations in the loop that must be performed ('sa_func_caller', 'sa_proc_caller' etc).
+    Also, there is procedure 'sp_dummy_loop' which does only loop with empty body, i.e. has no calls.
+    This SP, of course, will be performed for minimal time comparing to all other unit.
+
+    Number of iteration in each loop is defined by N_COUNT_PER_MEASURE.
+
+    Duration is measured as difference between psutil.Process(fb_pid).cpu_times() counters.
+    We do these measures <N_MEASURES> times for each SP, and each result is added to the list
+    which, in turn, is the source for median evaluation.
+
+    Finally, we get ratio between minimal and maximal medians (see 'median_ratio')
+    On Windows 8.1 usually this ratio is no more than 8 (before fix it was in the scope 22...33).
+    
+    Test is considered as passed if median_ratio less than threshold <MAX_RATIO>.
+NOTES:
+    [23.11.2023] pzotov
+    Fix in 4.x: ee357c9e6f081d3fd58e99aed99d15ec6476cedb (26-sep-2023)
+    Fix in 5.x: d621ffbe0cf2d43e13480628992180c28a5044fe (03-oct-2023; since build 5.0.0.1237).
+
+    Following is median ratio values for misc snapshots:
+    1. Before fix:
+        5.0.0.1236 : 33.50 33.50 22.00 22.00 33.00 33.00 22.00 22.00 32.50 22.00
+    2. After fix:
+        4.0.5.3031 :  7.00  7.00  4.67  7.00  4.67  7.50  7.00  7.50  7.00  7.00
+        5.0.0.1277 :  5.33  5.33  5.33  5.33  8.00  5.33  5.33  5.33  5.33  5.33
+        6.0.0.139  :  7.50  8.00  8.00  5.33  8.00  8.00  8.00  8.00  8.00  8.00
+
+    Checked on 6.0.0.139, 5.0.0.1277, 4.0.5.3031.
+"""
+
+import psutil
+import pytest
+from firebird.qa import *
+
+#--------------------------------------------------------------------
+def median(lst):
+    n = len(lst)
+    s = sorted(lst)
+    return (sum(s[n//2-1:n//2+1])/2.0, s[n//2])[n % 2] if n else None
+#--------------------------------------------------------------------
+
+###########################
+###   S E T T I N G S   ###
+###########################
+
+# How many times we call procedures:
+N_MEASURES = 11
+
+# How many iterations must be done:
+N_COUNT_PER_MEASURE = 100000
+
+# Maximal value for ratio between maximal and minimal medians
+#
+MAX_RATIO = 12
+##############
+
+init_script = \
+f'''
+    set term ^;
+    create or alter function sa_func returns varchar(10) as
+    begin
+        return '';
+    end
+    ^
+    -----------------------------------------------------------
+    create or alter procedure sa_proc returns (dummy_txt varchar(10)) as
+    begin
+        dummy_txt = '';
+        suspend;
+    end
+    ^
+    -----------------------------------------------------------
+    create or alter package pg_test as
+    begin
+        function pg_func returns varchar(10);
+        procedure pg_proc returns( dummy_txt varchar(10) );
+        procedure pg_func_caller(iter_cnt int);
+        procedure pg_proc_caller(iter_cnt int);
+    end
+    ^
+    recreate package body pg_test as
+    begin
+        function pg_func returns varchar(10) as
+        begin
+            return '';
+        end
+
+        procedure pg_proc returns( dummy_txt varchar(10)) as
+        begin
+            dummy_txt = '';
+            suspend;
+        end
+
+        procedure pg_func_caller(iter_cnt int) as
+            declare i int = 0;
+            declare dummy_txt varchar(10);
+        begin
+            while (i < iter_cnt) do
+            begin
+                dummy_txt = pg_func();
+                i = i + 1;
+            end  
+        end
+
+        procedure pg_proc_caller(iter_cnt int) as
+            declare i int = 0;
+            declare dummy_txt varchar(10);
+        begin
+            while (i < iter_cnt) do
+            begin
+                execute procedure pg_proc returning_values dummy_txt;
+                i = i + 1;
+            end  
+        end
+    
+    end
+    ^
+    -----------------------------------------------------------
+    create procedure sp_dummy_loop(iter_cnt int) as 
+        declare i int = 0;
+    begin
+        while (i < iter_cnt) do
+        begin
+            i = i + 1;
+        end  
+    end
+    ^
+    -----------------------------------------------------------
+    create procedure sa_func_caller(iter_cnt int) as 
+        declare i int = 0;
+        declare dummy_txt varchar(10);
+    begin
+        while (i < iter_cnt) do
+        begin
+            dummy_txt = sa_func();
+            i = i + 1;
+        end  
+    end
+    ^
+    -----------------------------------------------------------
+    create procedure sa_proc_caller(iter_cnt int) as 
+        declare i int = 0;
+        declare dummy_txt varchar(10);
+    begin
+        while (i < iter_cnt) do
+        begin
+            execute procedure sa_proc returning_values dummy_txt;
+            i = i + 1;
+        end  
+    end
+    ^
+    commit
+    ^
+'''
+
+db = db_factory(init = init_script)
+act = python_act('db')
+
+expected_stdout = """
+    Medians ratio: acceptable
+"""
+
+@pytest.mark.version('>=4.0.4')
+def test_1(act: Action, capsys):
+    
+    with act.db.connect() as con:
+        cur=con.cursor()
+        cur.execute('select mon$server_pid as p from mon$attachments where mon$attachment_id = current_connection')
+        fb_pid = int(cur.fetchone()[0])
+
+        sp_time = {}
+        for i in range(0, N_MEASURES):
+            for sp_name in ('sp_dummy_loop', 'sa_func_caller', 'sa_proc_caller', 'pg_test.pg_func_caller', 'pg_test.pg_proc_caller', ):
+                fb_info_init = psutil.Process(fb_pid).cpu_times()
+                cur.callproc( sp_name, (N_COUNT_PER_MEASURE,) )
+                fb_info_curr = psutil.Process(fb_pid).cpu_times()
+                sp_time[ sp_name, i ]  = max(fb_info_curr.user - fb_info_init.user, 0.000001)
+
+
+    sp_dummy_loop_median = median([v for k,v in sp_time.items() if k[0] == 'sp_dummy_loop'])
+    sa_func_caller_median = median([v for k,v in sp_time.items() if k[0] == 'sa_func_caller'])
+    sa_proc_caller_median = median([v for k,v in sp_time.items() if k[0] == 'sa_proc_caller'])
+    pg_func_caller_median = median([v for k,v in sp_time.items() if k[0] == 'pg_test.pg_func_caller'])
+    pg_proc_caller_median = median([v for k,v in sp_time.items() if k[0] == 'pg_test.pg_proc_caller'])
+
+    max_median = max(sa_func_caller_median, sa_proc_caller_median, pg_func_caller_median, pg_proc_caller_median)
+    min_median = max(sp_dummy_loop_median, 0.000001)
+    median_ratio = max_median / min_median
+
+    print( 'Medians ratio: ' + ('acceptable' if median_ratio <= MAX_RATIO else '/* perf_issue_tag */ POOR: %s, more than threshold: %s' % ( '{:9g}'.format(median_ratio), '{:9g}'.format(MAX_RATIO) ) ) )
+    if median_ratio > MAX_RATIO:
+        print('CPU times for each of {N_MEASURES} measures:')
+        for k,v in sp_time.items():
+            print(k,':::',v)
+        print(f'Median cpu time for {N_MEASURES} measures using loops for {N_COUNT_PER_MEASURE} iterations in each SP call:')
+        print('sp_dummy_loop_median:',sp_dummy_loop_median)
+        print('sa_func_caller_median:',sa_func_caller_median)
+        print('sa_proc_caller_median:',sa_proc_caller_median)
+        print('pg_func_caller_median:',pg_func_caller_median)
+        print('pg_proc_caller_median:',pg_proc_caller_median)
+        print('max_median:', max_median)
+        print('min_median:', min_median)
+
+    act.expected_stdout = expected_stdout
+    act.stdout = capsys.readouterr().out
+    assert act.clean_stdout == act.clean_expected_stdout