Rackspace Performance vs Standard Cloud Server Disk I/O

I just spun up a Rackspace High Performance Cloud Server and ran some i/o benchmarks on it and compared it to one of my standard cloud servers. Here are my findings.

This is the script that I ran to gather I/O stats:

#!/usr/bin/perl

use strict;
use warnings;

my $ioFilePath = "/root/iofile";
my $testNumber = "1";
my $ioStatsFile = "/root/iostats.txt";
my $testLength = "10";

if(-e $ioStatsFile) {
    `rm -f $ioStatsFile`;
}

while ($testNumber <= $testLength) {
    if(-e $ioFilePath) {
        print "Removing $ioFilePath before starting the test. Test: $testNumber.\n";
        `rm -f $ioFilePath`;
    }
    open(STATS, ">> $ioStatsFile");
        print STATS "-----------------------------------------\n";
        print STATS "\nTesting write speeds. Test: $testNumber.\n\n";
        print STATS `dd if=/dev/zero of=$ioFilePath bs=1M count=2048 2>> $ioStatsFile`;
        print STATS "\nTesting read speeds. Test $testNumber.\n\n";
        print STATS `dd if=$ioFilePath of=/dev/zero 2>> $ioStatsFile`;
        print STATS "-----------------------------------------\n\n";
    $testNumber++;        
}
close(STATS);

As you can see, it’s a simple test that writes 2GB of 0’s to a file, turns around and reads it, then runs the test nine more times.

First, here are the stats from my standard cloud server:

-----------------------------------------

Testing write speeds. Test: 1.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 22.2371 s, 96.6 MB/s

Testing read speeds. Test 1.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 25.4539 s, 84.4 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 2.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 20.1222 s, 107 MB/s

Testing read speeds. Test 2.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 23.5922 s, 91.0 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 3.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 16.7066 s, 129 MB/s

Testing read speeds. Test 3.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 22.2455 s, 96.5 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 4.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 16.0221 s, 134 MB/s

Testing read speeds. Test 4.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 22.5168 s, 95.4 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 5.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 15.4431 s, 139 MB/s

Testing read speeds. Test 5.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 22.5327 s, 95.3 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 6.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 15.9895 s, 134 MB/s

Testing read speeds. Test 6.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 23.5538 s, 91.2 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 7.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 15.9522 s, 135 MB/s

Testing read speeds. Test 7.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 23.3412 s, 92.0 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 8.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 16.306 s, 132 MB/s

Testing read speeds. Test 8.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 22.0596 s, 97.3 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 9.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 15.1251 s, 142 MB/s

Testing read speeds. Test 9.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 22.169 s, 96.9 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 10.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 16.9925 s, 126 MB/s

Testing read speeds. Test 10.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 22.6342 s, 94.9 MB/s
-----------------------------------------

Average Write Speed: 127.46 MB/s

Average Read Speed: 93.49 MB/s

Now here are the results from the High Performance Server:

-----------------------------------------

Testing write speeds. Test: 1.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 6.65244 s, 323 MB/s

Testing read speeds. Test 1.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 12.4408 s, 173 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 2.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 8.77157 s, 245 MB/s

Testing read speeds. Test 2.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 11.7669 s, 183 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 3.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 4.14636 s, 518 MB/s

Testing read speeds. Test 3.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 12.9577 s, 166 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 4.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 4.13664 s, 519 MB/s

Testing read speeds. Test 4.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 11.2337 s, 191 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 5.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 4.22346 s, 508 MB/s

Testing read speeds. Test 5.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 12.9633 s, 166 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 6.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 4.12969 s, 520 MB/s

Testing read speeds. Test 6.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 12.8751 s, 167 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 7.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 4.2136 s, 510 MB/s

Testing read speeds. Test 7.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 12.1281 s, 177 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 8.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 4.20004 s, 511 MB/s

Testing read speeds. Test 8.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 12.2221 s, 176 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 9.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 4.20901 s, 510 MB/s

Testing read speeds. Test 9.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 13.1822 s, 163 MB/s
-----------------------------------------

-----------------------------------------

Testing write speeds. Test: 10.

2048+0 records in
2048+0 records out
2147483648 bytes (2.1 GB) copied, 4.17714 s, 514 MB/s

Testing read speeds. Test 10.

4194304+0 records in
4194304+0 records out
2147483648 bytes (2.1 GB) copied, 11.1146 s, 193 MB/s
-----------------------------------------

Average Write Speed: 467.8 MB/s

Average Read Speed: 175.5 MB/s

(467.8 - 127.46) / 127.46 = 2.67
(175.5 - 93.49) / 93.49 = .877

As you can see, given my simple test, High Performance Cloud Servers have a write speed that is 267% faster and a read speed that is 88% faster than the standard Cloud Servers from Rackspace. Pretty interesting!