performance measurements

Each table row shows performance measurements for this C gcc program with a particular command-line input value N.

 N  CPU secs Elapsed secs Memory KB Code B ≈ CPU Load
250,0000.470.19?1535  45% 94% 21% 95%
2,500,0003.861.4525,5361535  92% 30% 98% 48%
25,000,00036.2413.34135,6121535  68% 81% 96% 28%

Read the ↓ make, command line, and program output logs to see how this program was run.

Read k-nucleotide benchmark to see what this program should do.


gcc version 4.9.2 (Ubuntu 4.9.2-10ubuntu13)

 k-nucleotide C gcc #9 program source code

// The Computer Language Benchmarks Game
// Contributed by Jeremy Zerfas

// This controls the initial size used for the hash tables.
// This controls the maximum length for each set of nucleotide sequence
// frequencies and each nucleotide sequence count output by this program.

#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

typedef struct ht_ht ht_ht;
typedef struct ht_node ht_node;

// intptr_t should be the native integer type on most sane systems.
typedef intptr_t intnative_t;

// The hash table implementation provided by simple_hash3.h doesn't
// automatically grow hash tables (although the chained linked lists can grow
// infinitely long) and it also doesn't provide any function for growing a hash
// table so we create our own function for checking the hash table density and
// growing the hash table if necessary.
static void check_Hash_Table_Density_And_Grow_If_Necessary(
  ht_ht ** const hash_Table_To_Check){
   if(ht_count(*hash_Table_To_Check) > (*hash_Table_To_Check)->size){
      // Create a new grown_Hash_Table which is at least four times the size
      // of the current hash_Table_To_Check.
      ht_ht * grown_Hash_Table=ht_create(4 * (*hash_Table_To_Check)->size);

      // Copy all the ht_nodes from the current hash_Table_To_Check to the new
      // grown_Hash_Table.
      ht_node *HT_Node_Pointer=ht_first(*hash_Table_To_Check);
      for(intnative_t i=0; i<ht_count(*hash_Table_To_Check); i++){
         ht_find_new(grown_Hash_Table, HT_Node_Pointer->key)->val=

      // Destroy the old hash_Table_To_Check and update its pointer to point
      // to the new grown_Hash_Table.

// Function to use when sorting ht_nodes with qsort() later. ht_nodes with
// larger values will come first and in cases of identical values then ht_nodes
// with smaller keys will come first.
static int HT_Node_Compare(const void * const uncasted_Left_HT_Node,
  const void * const uncasted_Right_HT_Node){
   const ht_node * left_HT_Node=uncasted_Left_HT_Node,
     * right_HT_Node=uncasted_Right_HT_Node;

   // Sort based on ht_node values.
   if(left_HT_Node->val < right_HT_Node->val) return 1;
   if(left_HT_Node->val > right_HT_Node->val) return -1;

   // If we got here then both items have the same value so then sort based on
   // key.
   if(left_HT_Node->key > right_HT_Node->key)
      return 1;
      return -1;

// Macro to convert a nucleotide character to a code. Note that upper and lower
// case ASCII letters only differ in the fifth bit from the right and we only
// need the three least significant bits to differentiate the letters 'A', 'C',
// 'G', and 'T'. Spaces in this array/string will never be used as long as
// characters other than 'A', 'C', 'G', and 'T' aren't used.
#define code_For_Nucleotide(nucleotide) (" \0 \1\3  \2"[nucleotide & 0x7])

// And one more macro to convert the codes back to nucleotide characters.
#define nucleotide_For_Code(code) ("ACGT"[code & 0x3])

// Generate frequences for all nucleotide sequences in sequences that are of
// length sequence_Length and then save it to output.
static void generate_Frequencies_For_Sequences(const char * const sequences,
  const intnative_t sequences_Length, intnative_t sequence_Length,
  char * const output){
   ht_ht * hash_Table=ht_create(INITIAL_HASH_TABLE_SIZE);

   // Add all the sequences of sequence_Length to hash_Table.
   uint64_t key=0;
   for(intnative_t i=0; i<sequences_Length; i++){
      const uint64_t mask=((uint64_t)1<<2*sequence_Length)-1;
      key=(key<<2 & mask) | sequences[i];
         ht_find_new(hash_Table, key)->val++;

   // Create an array of ht_nodes from hash_Table.
   intnative_t HT_Nodes_Array_Size=hash_Table->items;
   ht_node * HT_Nodes_Array=malloc(HT_Nodes_Array_Size*sizeof(ht_node));
   ht_node * HT_Node_Pointer=ht_first(hash_Table);
   for(intnative_t i=0; i<HT_Nodes_Array_Size; i++){


   // Sort HT_Nodes_Array.
   qsort(HT_Nodes_Array, HT_Nodes_Array_Size, sizeof(ht_node),

   // Print the frequencies for each nucleotide sequence.
   for(intnative_t output_Position=0, i=0; i<HT_Nodes_Array_Size; i++){
      char nucleotide_Sequence[sequence_Length+1];
      for(intnative_t j=sequence_Length-1; j>-1; j--){

      // Output the frequency for nucleotide_Sequence to output.
        MAXIMUM_OUTPUT_LENGTH-output_Position, "%s %.3f\n",
        nucleotide_Sequence, 100.0f*HT_Nodes_Array[i].val/sequences_Length);


// Generate a count for the number of times nucleotide_Sequence appears in
// sequences and then save it to output.
static void generate_Count_For_Sequence(const char * const sequences,
  const intnative_t sequences_Length, const char * const nucleotide_Sequence,
  char * const output){
   const intnative_t nucleotide_Sequence_Length=strlen(nucleotide_Sequence);

   ht_ht * hash_Table=ht_create(INITIAL_HASH_TABLE_SIZE);

   uint64_t key=0;
   for(intnative_t i=0; i<sequences_Length; i++){
      const uint64_t mask=((uint64_t)1<<2*nucleotide_Sequence_Length)-1;
      key=(key<<2 & mask) | sequences[i];
         ht_find_new(hash_Table, key)->val++;

   // Generate key for the sequence.
   for(intnative_t i=0; i<nucleotide_Sequence_Length; i++)
      key=(key<<2) | code_For_Nucleotide(nucleotide_Sequence[i]);

   // Output the count for nucleotide_Sequence to output.
   intnative_t count=ht_find(hash_Table, key)->val;
   snprintf(output, MAXIMUM_OUTPUT_LENGTH, "%jd\t%s", (intmax_t)count,


int main(){
   char buffer[4096];

   // Find the start of the third nucleotide sequence.
   while(fgets(buffer, sizeof(buffer), stdin) && memcmp(">THREE", buffer,

   // Start with 1 MB of storage for reading in the nucleotide sequence and
   // grow exponentially.
   intnative_t nucleotide_Sequence_Capacity=1048576;
   intnative_t nucleotide_Sequence_Size=0;
   char * nucleotide_Sequence=malloc(nucleotide_Sequence_Capacity);

   // Start reading and encoding the third nucleotide sequence.
   while(fgets(buffer, sizeof(buffer), stdin) && buffer[0]!='>'){
      for(intnative_t i=0; buffer[i]!='\0'; i++){

      // Make sure we still have enough memory allocated for any potential
      // nucleotides in the next line.
      if(nucleotide_Sequence_Capacity-nucleotide_Sequence_Size <

   // Free up any leftover memory.
   nucleotide_Sequence=realloc(nucleotide_Sequence, nucleotide_Sequence_Size);

   char output_Buffer[7][MAXIMUM_OUTPUT_LENGTH];

   // Do the following functions in parallel.
   #pragma omp parallel sections
      #pragma omp section
      { generate_Frequencies_For_Sequences(nucleotide_Sequence,
        nucleotide_Sequence_Size, 1, output_Buffer[0]); }
      #pragma omp section
      { generate_Frequencies_For_Sequences(nucleotide_Sequence,
        nucleotide_Sequence_Size, 2, output_Buffer[1]); }

      #pragma omp section
      { generate_Count_For_Sequence(nucleotide_Sequence,
        nucleotide_Sequence_Size, "GGT", output_Buffer[2]); }
      #pragma omp section
      { generate_Count_For_Sequence(nucleotide_Sequence,
        nucleotide_Sequence_Size, "GGTA", output_Buffer[3]); }
      #pragma omp section
      { generate_Count_For_Sequence(nucleotide_Sequence,
        nucleotide_Sequence_Size, "GGTATT", output_Buffer[4]); }
      #pragma omp section
      { generate_Count_For_Sequence(nucleotide_Sequence,
        nucleotide_Sequence_Size, "GGTATTTTAATT", output_Buffer[5]); }
      #pragma omp section
      { generate_Count_For_Sequence(nucleotide_Sequence,
        nucleotide_Sequence_Size, "GGTATTTTAATTTATAGT", output_Buffer[6]); }

   for(intnative_t i=0; i<7; printf("%s\n", output_Buffer[i++]));


   return 0;

 make, command-line, and program output logs

Wed, 20 May 2015 06:13:06 GMT

/usr/bin/gcc -pipe -Wall -O3 -fomit-frame-pointer -march=native -fopenmp -std=c99 -include Include/simple_hash3.h knucleotide.gcc-9.c -o knucleotide.gcc-9.gcc_run 
In file included from <command-line>:0:0:
./Include/simple_hash3.h:195:31: warning: ‘ht_node_create’ is static but used in inline function ‘ht_find_new’ which is not static
   return(ht->tbl[hash_code] = ht_node_create(key));
./Include/simple_hash3.h:191:24: warning: ‘ht_node_create’ is static but used in inline function ‘ht_find_new’ which is not static
   return (prev->next = ht_node_create(key));
./Include/simple_hash3.h:173:21: warning: ‘ht_hashcode’ is static but used in inline function ‘ht_find_new’ which is not static
     int hash_code = ht_hashcode(ht, key);
./Include/simple_hash3.h:156:21: warning: ‘ht_hashcode’ is static but used in inline function ‘ht_find’ which is not static
     int hash_code = ht_hashcode(ht, key);
rm knucleotide.gcc-9.c
0.30s to complete and log all make actions

./knucleotide.gcc-9.gcc_run 0 < knucleotide-input25000000.txt

A 30.295
T 30.151
C 19.800
G 19.754

AA 9.177
TA 9.132
AT 9.131
TT 9.091
CA 6.002
AC 6.001
AG 5.987
GA 5.984
CT 5.971
TC 5.971
GT 5.957
TG 5.956
CC 3.917
GC 3.911
CG 3.909
GG 3.902

1471758	GGT
446535	GGTA
47336	GGTATT

Revised BSD license

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