var fs = require('fs');
var Buffer = require('buffer').Buffer;

var path = "/tmp/wt.dat";
var tsize = 1000 * 1048576;
var bsizes = [1024, 4096, 8192, 16384, 32768, 65536];

function bufit(size) {
  var buf = new Buffer(size);
  for (var i = 0; i  0) {
      //if (remaining % 90000 == 0) console.error("remaining: %d", remaining);
      //process.nextTick(dowrite);
    } else {
      s.emit('done')
      s.end();
    }
  }

  s.on('drain', function () {
    dowrite();
  });

  dowrite();

  return s;
}

function readtest(size, bsize) {
  var s = fs.createReadStream(path, {'flags': 'r', 'encoding': 'binary', 'mode': 0644, 'bufferSize': bsize});
  s.addListener("data", function (chunk) {
    // got a chunk...
    
  });
  return s;
}

function wt(tsize, bsize, done) {
  var start = Date.now();
  s = writetest(tsize, bsizes[0]);
  s.addListener('close', function() {
    var end = Date.now();
    var diff = end - start;
    console.log('Wrote '+ tsize +' bytes in '+  diff/1000 +'s using '+ bsize +' byte buffers: '+  ((tsize/(diff/1000)) / 1048576) +' mB/s');
    done();
  });
}

function rt(tsize, bsize, done) {
  var start = Date.now();
  s = readtest(tsize, bsizes[0]);
  s.addListener('close', function() {
    var end = Date.now();
    var diff = end - start;
    console.log('Read '+ tsize +' bytes in '+  diff/1000 +'s using '+ bsize +' byte buffers: '+  ((tsize/(diff/1000)) / 1048576) +' mB/s');
    done();
  });
}

var bs= 0;

function nextwt() {
  if (bsizes.length