Extracting a single field out of some data using FBSON and Subdoc

fbsonmapfun.cc

#include <sys/time.h>
#include <fstream>
#include <vector>

#include "fbson/FbsonJsonParser.h"


// From http://stackoverflow.com/a/1861493/935109
typedef unsigned long long timestamp_t;
static timestamp_t get_timestamp ()
{
  struct timeval now;
  gettimeofday (&now, NULL);
  return  now.tv_usec + (timestamp_t)now.tv_sec * 1000000;
}


// Read the docs we want to process
std::vector<std::string> readData(const char *filename)
{
  std::ifstream infile(filename);
  std::string line;
  std::vector<std::string> file_contents;

  while (std::getline(infile, line))
  {
    file_contents.push_back(line);
  }
  return file_contents;
}


int main(int argc, char* argv[]) {
  // Read the docs we want to process
  std::vector<std::string> data = readData(
      "/home/vmx/src/c/v8/mapfun/data_fbson.txt");

  // The data as FBSON
  std::vector<std::string> bin_data;

  // Create FBSON out of JSON
  for (size_t ii = 0; ii < data.size(); ii++) {
    fbson::FbsonJsonParser parser;

    if (!parser.parse(data[ii])) {
      printf("%d\n", parser.getErrorCode());
      return (int)parser.getErrorCode();
    }
    bin_data.push_back(std::string(
        parser.getWriter().getOutput()->getBuffer(),
        parser.getWriter().getOutput()->getSize()));
  }

  // Extract the title and time it
  timestamp_t t0 = get_timestamp();
  for(std::vector<std::string>::size_type i = 0; i != bin_data.size(); i++) {
    auto fbsonDoc = fbson::FbsonDocument::createValue(bin_data[i].c_str(),
                                                      bin_data[i].size());

    std::string key_path = "title";
    fbson::FbsonValue *result_val = fbsonDoc->findPath(key_path.c_str(),
                                                       key_path.size());
    std::string result = std::string(result_val->getValuePtr(),
                                     result_val->size());
    std::cout << result << std::endl;
  }
  timestamp_t t1 = get_timestamp();
  double secs = (t1 - t0) / 1000000.0L;
  std::cout << "It took: " << secs << "s" << std::endl;

  return 0;
}

subdocmapfun.cc

#include <sys/time.h>
#include <iostream>
#include <fstream>
#include <vector>

#include "subdoc/operations.h"


// From http://stackoverflow.com/a/1861493/935109
typedef unsigned long long timestamp_t;
static timestamp_t get_timestamp ()
{
  struct timeval now;
  gettimeofday (&now, NULL);
  return  now.tv_usec + (timestamp_t)now.tv_sec * 1000000;
}


// Read the docs we want to process
std::vector<std::string> readData(const char *filename)
{
  std::ifstream infile(filename);
  std::string line;
  std::vector<std::string> file_contents;

  while (std::getline(infile, line))
  {
    file_contents.push_back(line);
  }
  return file_contents;
}


int main(int argc, char* argv[]) {
  // Read the docs we want to process
  std::vector<std::string> data = readData(
      "/home/vmx/src/c/v8/mapfun/data_fbson.txt");

  // Extract the title and time it
  timestamp_t t0 = get_timestamp();
  for (size_t ii = 0; ii < data.size(); ii++) {
      Subdoc::Operation op;
      Subdoc::Result res;
      uint8_t opcode = Subdoc::Command::GET;

      res.clear();
      op.set_doc(data[ii]);
      op.set_result_buf(&res);

      Subdoc::Error rv = op.op_exec("title");
      if (!rv.success()) {
          std::cout << rv.description() << std::endl;
          throw rv;
      }

      std::string match = res.matchloc().to_string();
      std::cout << match << std::endl;
  }
  timestamp_t t1 = get_timestamp();
  double secs = (t1 - t0) / 1000000.0L;
  std::cout << "It took: " << secs << "s" << std::endl;

  return 0;
}

One thing jumps out straight away:
#42: Creating a Subdoc::Operation is expensive - try moving the creation of this out of the loop, and then call op.clear() after each call to op_exec

Also this will be massively dependant on input data.