Line data    Source code

       1              : /*-------------------------------------------------------------------------
       2              :  *
       3              :  * test_json_parser_perf.c
       4              :  *    Performance test program for both flavors of the JSON parser
       5              :  *
       6              :  * Copyright (c) 2024-2026, PostgreSQL Global Development Group
       7              :  *
       8              :  * IDENTIFICATION
       9              :  *    src/test/modules/test_json_parser/test_json_parser_perf.c
      10              :  *
      11              :  * This program tests either the standard (recursive descent) JSON parser
      12              :  * or the incremental (table driven) parser, but without breaking the input
      13              :  * into chunks in the latter case. Thus it can be used to compare the pure
      14              :  * parsing speed of the two parsers. If the "-i" option is used, then the
      15              :  * table driven parser is used. Otherwise, the recursive descent parser is
      16              :  * used.
      17              :  *
      18              :  * The remaining arguments are the number of parsing iterations to be done
      19              :  * and the file containing the JSON input.
      20              :  *
      21              :  *-------------------------------------------------------------------------
      22              :  */
      23              : 
      24              : #include "postgres_fe.h"
      25              : #include "common/jsonapi.h"
      26              : #include "common/logging.h"
      27              : #include "lib/stringinfo.h"
      28              : #include "mb/pg_wchar.h"
      29              : #include <stdio.h>
      30              : #include <string.h>
      31              : 
      32              : #define BUFSIZE 6000
      33              : 
      34              : int
      35            0 : main(int argc, char **argv)
      36              : {
      37            0 :         char            buff[BUFSIZE];
      38            0 :         FILE       *json_file;
      39            0 :         JsonParseErrorType result;
      40            0 :         JsonLexContext *lex;
      41            0 :         StringInfoData json;
      42            0 :         int                     n_read;
      43            0 :         int                     iter;
      44            0 :         int                     use_inc = 0;
      45              : 
      46            0 :         pg_logging_init(argv[0]);
      47              : 
      48            0 :         initStringInfo(&json);
      49              : 
      50            0 :         if (strcmp(argv[1], "-i") == 0)
      51              :         {
      52            0 :                 use_inc = 1;
      53            0 :                 argv++;
      54            0 :         }
      55              : 
      56            0 :         sscanf(argv[1], "%d", &iter);
      57              : 
      58            0 :         if ((json_file = fopen(argv[2], PG_BINARY_R)) == NULL)
      59            0 :                 pg_fatal("Could not open input file '%s': %m", argv[2]);
      60              : 
      61            0 :         while ((n_read = fread(buff, 1, 6000, json_file)) > 0)
      62              :         {
      63            0 :                 appendBinaryStringInfo(&json, buff, n_read);
      64              :         }
      65            0 :         fclose(json_file);
      66            0 :         for (int i = 0; i < iter; i++)
      67              :         {
      68            0 :                 if (use_inc)
      69              :                 {
      70            0 :                         lex = makeJsonLexContextIncremental(NULL, PG_UTF8, false);
      71            0 :                         result = pg_parse_json_incremental(lex, &nullSemAction,
      72            0 :                                                                                            json.data, json.len,
      73              :                                                                                            true);
      74            0 :                         freeJsonLexContext(lex);
      75            0 :                 }
      76              :                 else
      77              :                 {
      78            0 :                         lex = makeJsonLexContextCstringLen(NULL, json.data, json.len,
      79              :                                                                                            PG_UTF8, false);
      80            0 :                         result = pg_parse_json(lex, &nullSemAction);
      81            0 :                         freeJsonLexContext(lex);
      82              :                 }
      83            0 :                 if (result != JSON_SUCCESS)
      84            0 :                         pg_fatal("unexpected result %d (expecting %d) on parse",
      85              :                                          result, JSON_SUCCESS);
      86            0 :         }
      87            0 :         exit(0);
      88              : }