title: Encrypted Vs Unencrypted EBS Volumes AWS
body: <p>We are testing standard EBS volume, EBS volume with encryption on EBS optimized m3.xlarge EC2 instance.</p>
  
  <p>While analyzing the test results, we came to know that</p>
  
  <p>EBS  volume with encryption is taking lesser time during read, write, read/write operations as compared to EBS without encryption. 
  I think there will be an effect of latency on encrypted EBS volume  because of extra encryption overhead on every I/O request. </p>
  
  <p>What will be the appropriate reason why EBS encrypted volumes are faster than normal EBS volumes??</p>
  
  <p>Expected results should be that EBS should yield better results that Encrypted EEBS.</p>
  
  <p><strong>Results :</strong></p>
  
  <p><strong>Encrpted EBS results:</strong></p>
  
  <pre><code>sysbench 0.4.12:  multi-threaded system evaluation benchmark
  
  Running the test with following options:
  Number of threads: 8
  Initializing random number generator from timer.
  
  
  Extra file open flags: 16384
  8 files, 512Mb each
  4Gb total file size
  Block size 16Kb
  Calling fsync() at the end of test, Enabled.
  Using synchronous I/O mode
  Doing sequential write (creation) test
  Threads started!
  Done.
  
  Operations performed:  0 Read, 262144 Write, 8 Other = 262152 Total
  Read 0b  Written 4Gb  Total transferred 4Gb  (11.018Mb/sec)
    705.12 Requests/sec executed
  
  Test execution summary:
      total time:                          371.7713s
      total number of events:              262144
      total time taken by event execution: 2973.6874
      per-request statistics:
           min:                                  1.06ms
           avg:                                 11.34ms
           max:                               3461.45ms
           approx.  95 percentile:               1.72ms
  </code></pre>
  
  <p><strong>EBS results:</strong></p>
  
  <pre><code>sysbench 0.4.12:  multi-threaded system evaluation benchmark
  
  Running the test with following options:
  Number of threads: 8
  Initializing random number generator from timer.
  
  
  Extra file open flags: 16384
  8 files, 512Mb each
  4Gb total file size
  Block size 16Kb
  Calling fsync() at the end of test, Enabled.
  Using synchronous I/O mode
  Doing sequential write (creation) test
  Threads started!
  Done.
  
  Operations performed:  0 Read, 262144 Write, 8 Other = 262152 Total
  Read 0b  Written 4Gb  Total transferred 4Gb  (6.3501Mb/sec)
    406.41 Requests/sec executed
  
  Test execution summary:
      total time:                          645.0251s
      total number of events:              262144
      total time taken by event execution: 5159.7466
      per-request statistics:
           min:                                  0.88ms
           avg:                                 19.68ms
           max:                               5700.71ms
           approx.  95 percentile:               6.31ms
  </code></pre>
  
  <p>please help me resolve this issue.</p>