perf/perftest.h

   1 /*
   2   Copyright 2009 Kristian Nielsen
   3
   4   This file is part of BeeDB.
   5
   6   Foobar is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 2 of the License, or
   9   (at your option) any later version.
  10
  11   Foobar is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with Foobar.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20
  21 /*
  22   Helper code for BeeDB performance regression testing.
  23 */
  24
  25 #include <stdarg.h>
  26
  27 /* For now, we are libperfmon specific. */
  28 #include <perfmon/pfmlib_perf_event.h>
  29
  30
  31 class perftest {
  32  public:
  33   /* The number of times to run each test benchmark different measurements. */
  34   static const int num_runs= 6;
  35
  36   /* Virtual class, performance tests are implemented as derived classes. */
  37   class test {
  38   public:
  39     /*
  40       Constructor for one test case.
  41
  42       Test description parameters:
  43
  44       text
  45           Overall name of the test. Eg. "btree insert", or "memcpy".
  46
  47       variant
  48           Identifies different variants of the test identified by parameter
  49           text. Could be different implementations of the same algorithm
  50           compared against each other. Idea is it makes sense to directly
  51           compare performance of different variants against each other.
  52
  53       param1
  54       param2
  55           These are arbitrary parameters that the performance could be graphed
  56           against. Idea is that the tests will run for different values of
  57           these parameters, with eg. graphs drawn with performance as a
  58           function of these parameters. Either or both can be left NULL,
  59           meaning there is no such parameter to graph against. Could be eg.
  60           buffer size, or number of columns in a row.
  61
  62       workunits
  63           This is the amount of work done during one iteration of the loop
  64           being timed in the run() method. Idea is that workunits*iterations
  65           would be some kind of measure of total amount of work done.
  66
  67       Note that it is explicitly permitted to pass pointers for text, variant,
  68       param1, and param2 that are initialised only after calling this
  69       constructor (but before calling run()).
  70      */
  71     test(perftest *tester, const char *text, const char *variant= NULL,
  72          const char *param1= NULL, const char *param2= NULL,
  73          uint64_t workunits= 0);
  74     virtual void run(uint64_t loops) = 0;
  75     virtual ~test() = 0;
  76
  77     double gettime() { return tester->gettime(); }
  78     void force_value(uint64_t value) { tester->force_value(value); }
  79     void fatal_error(const char *format, ...) NORETURN PRINTF_LIKE(2, 3);
  80
  81     void prepare(int run) { current_run= run; }
  82
  83     const char *text;
  84     const char *variant;
  85     const char *param1;
  86     const char *param2;
  87     uint64_t workunits;
  88     double elapsed_time[num_runs];
  89
  90   protected:
  91     /*
  92       Start the timer running.
  93       Call just before starting the computation to be tested.
  94     */
  95     void start();
  96     void record_time(const char *text);
  97
  98     perftest *const tester;
  99
 100   private:
 101     int current_run;
 102     double start_time;
 103   };
 104
 105   /* Methods. */
 106   perftest();
 107   ~perftest();
 108   void run_test(test *t, uint64_t loops);
 109   void start_perfmon(int run);
 110   void record_perfmon(int run);
 111   void record_perfmon_not_time_critical(int run);
 112   void report_perfmon();
 113
 114   static double gettime();
 115   static void force_value(uint64_t value);
 116   static void fatal_error(const char *format, ...) NORETURN PRINTF_LIKE(1, 2);
 117   static void fatal_error(const char *format, va_list ap) NORETURN PRINTF_LIKE(1, 0);
 118
 119   /* perf_event specific stuff. */
 120   static const unsigned int num_fixed_counters= 2;
 121   static const unsigned int num_unfixed_counters= 2;
 122   static const unsigned int num_counters=
 123     num_fixed_counters + num_unfixed_counters;
 124
 125  private:
 126   perf_event_attr perf_attr[num_runs][num_counters];
 127   const char *perf_event_names[num_runs][num_counters];
 128   uint64_t perf_counter_values[num_runs][num_counters];
 129   int perf_fds[num_counters];
 130
 131   /*
 132     Quick&dirty way to disable all performance counter usage (to allow
 133     external profiling tools to be used.
 134   */
 135   static const bool skip_perfmon= false;
 136
 137   void prepare_perfmon_event(int idx, int run, const char *event_name);
 138   void setup_perfmon();
 139 };
 140
 141 #include "port/perftest.h"