Virtualization Performance: Linux VMs on ESXi

We introduced our new vApus FOS (For Open Source) server workloads in our review of the Facebook "Open Compute" servers. In a nutshell, it a mix of four VMs with open source workloads: two PhpBB websites (Apache2, MySQL), one OLAP MySQL "Community server 5.1.37" database, and one VM with VMware's open source groupware Zimbra 7.1.0. Zimbra is quite a complex application as it contains the following components:

  • Jetty, the web application server
  • Postfix, an open source mail transfer agent
  • OpenLDAP software, user authentication
  • MySQL is the database
  • Lucene full-featured text and search engine
  • ClamAV, an anti-virus scanner
  • SpamAssassin, a mail filter
  • James/Sieve filtering (mail)

All VMs are based on a minimal CentOS 5.6 setup with VMware Tools installed. All our current virtualization testing is on top of the hypervisor which we know best: ESXi (5.0). CentOS 5.6 is not ideal for the Interlagos Opteron, but we designed the benchmark a few months ago. It took us weeks to get this benchmark working and repeatable (especially the latter is hard). For example it was not easy to get Zimbra fully configured and properly benchmarked due to the complex usage patterns and high I/O usage. Besides, the reality is that VMs often contain older operating systems. We hope to show some benchmarks based on Linux kernel version 3.0 or later in our next article.

We tested with five tiles (one tile = four VMs). Each tile needs seven vCPUs, so the test requires 35 vCPUs.

vApus FOS

The Opteron 6276 stays close to the more expensive Xeons. That makes the Opteron server the one with the best performance per dollar. Still, we feel a bit underwhelmed as the Opteron 6276 fails to outperform the previous Opteron by a tangible margin.

The benchmark above measures throughput. Response times are even more important. Let us take a look at the table below, which gives you the average response time per VM:

vApus FOS Average Response Times (ms), lower is better!
CPU PhpBB1 PHPBB2 MySQL OLAP Zimbra
AMD Opteron 6276 737 587 170 567
AMD Opteron 6174 707 574 118 630
Intel Xeon X5670 645 550 63 593
Intel Xeon X5650 678 566 102 655

The Xeon X5670 wins a landslide victory in MySQL. MySQL has always scaled better with clock speed than with cores, so we expect that clock speed played a major role here. The same is true for our first VM: this VM gets only one CPU and as result runs quicker on the Xeon. In the other applications, the Opteron's higher (integer) core count starts to show. However, AMD cannot really be satisfied with the fact that the old Opteron 6174 delivers much better MySQL performance. We suspect that the high latency L2 cache and higher branch misprediction penalty (20 vs 12) is to blame. MySQL performance is characterized by a relatively high amount of branches and a lot of accesses to the L2. The Bulldozer server does manage to get the best response time on our Zimbra VM, however, so it's not a complete loss.

Performance per watt remains the most important metric for a large part of the server market. So let us check out the power consumption that we measured while we ran vApus FOS.

vApus FOS Power Consumption

The power consumption numbers are surprising to say the least. The Opteron 6174 needs quite a bit less energy than the two other contenders. That is bad news for the newest Opteron. We found out later that some tinkering could improve the situation, as we will see further.

Benchmark Configuration Measuring Real-World Power Consumption, Part One
Comments Locked

106 Comments

View All Comments

  • zappb - Tuesday, November 29, 2011 - link

    Thanks Johan for the ungodly amount of time you and your team spent on this review, also thanks to all contributors to the comments which was very useful to get more context to someone like myself who is not very up to speed with server tech.

    The 45 Watt and 65 watt Opterons not mentioned on the front page of the article (but mentioned in the comments - are these based on Interlagos?)

    To me it looks like a big win for AMD - and these benchmarks are are not even optimised for the architecture (Linux kernel 3 was not used - can't wait to see updated benchmarks, something like FreeBSD or when we get an updated scheduler for the windows server OS's...should make a big difference.

    Really low idle power consumption is nice, and Im planning to pick one of these up (for home use) to play around with FreeBSD, vm's, etc...just for training purposes,

    The other point about Intel's sandybridge Xeons, these are just going to be 8 core 3960x right? Which may not change the current server landscape very much depending on their prices.
  • JWesterby - Friday, February 10, 2012 - link

    Respect is due, Johan! You did a very useful review under significant limitations. The very best part is to point an unbiased light at a damned interesting CPU. There is an important "next step," which I will address shortly.

    As always, just the mention of AMD brings out hysterical attacks. One would think we were talking about Stem Cell research!! There is no real discussion -- it's pitchforks, lit torches, and a stake ready for poor Johan and anyone else ready and willing to consider the mere possibility that AMD have produced worthy technology!!

    Computer technology - doing it, anyway - has changed. It's become ALL about the bloody money, and the "culture" of the people doing technology has also changed -- it has become much more cut-throat, there is far less collegiality, and the number of people willing to take risks on projects has become really uncommon. Qualified people doing serious technology just because they can is uncommon.

    There is no end to posers (including some on this board), Machiavellian Fortune 500 IT managers, and "Project Managers" who are clueless (there ARE some great IT managers and wonderful PM's but their numbers are shrinking). My hat to those in Open Source - they are the Last Bastion of decency for the sake of decency, and technology merely for the joy of doing it !!

    "Back in the day" people seemed really into the technology, solving difficult problems, and making good things happen. There was truly a culture. For example not taking a moment to help someone on the team or otherwise made you a jerk. Development was a craft or an art, and we were all in it together. We are loosing that, and it's become more dog-eat-dog with a kind of mean spirit. What a shame. Many of the comments here are perfect examples -- people who would rather burn down the temple than give a new and challenging technology a good think.

    Personally I can't wait to get my hands on a couple of AMD's new CPU's, build a decent server, and carefully work out the issues with patience. These new Opterons are like a whole new tech that may be the beginning of all new territory.

    My passion and some professional work is coding at the back end in C/C++ and I'm just beginning to understand CUDA and using GPU's to beef up parallel code. My work is all around (big) data warehousing, cutting edge columnar databases, almost everything running virtual, all the way through to analytics on BI platforms. I do all of that both on MS Server 2008, Solaris and FreeBSD. All that is a perfect environment to test AMD's "new territory."

    Probably worth a blog at some point because these processors are new territory and using them well will take some work just keeping track of all the small things that shake out. That's the "next step" that this and other reviews require to really understand AMD's Bulldozers. Doing that well, if AMD is right with these chips, means being able to build some great back-end servers at a much more approachable price; more importantly without paying an "Intel" tax, and in the end having two strong vendors and thereby more freedom to make the best choice for the requirement.
  • PhotoPrint - Sunday, December 25, 2011 - link

    you should make fair comparison at the same price range!
    lts like comparing GTX580 VS AMD RADEON 6950!
  • g101 - Wednesday, January 11, 2012 - link

    Wow, anad let the truth about bulldozer leak out.
  • ppennisi - Wednesday, March 7, 2012 - link

    To obtain maximum performance from my Dell R715 server equipped with dual Interlagos processor I had to DISABLE C1E in the BIOS.

    Under VMware the machines performance changed completely, almost doubled in performance.

    Maybe you should try it.
  • anti_shill - Monday, April 2, 2012 - link

    Here's a more accurate reflection of Bulldozer/ interlagos performance, untainted by intel ad bucks...

    http://www.phoronix.com/scan.php?page=article&...

    But if u really want to see what the true story is, have a look at AMD's stock price lately, and their server wins. They absolutely smoke intel on virtualization, and anything that requires a lot of threads. It's not even close. That would be the reason this review pits Interlagos against an Intel processor that costs twice as much.

Log in

Don't have an account? Sign up now