Thursday, February 24, 2011

Big VMs Aren't What They Used To Be

I've had the privilege to work on some of the current generation Intel Westmere and Nehalem EX servers over the past few months.  This testing has focused on Oracle RAC (which has been pretty cool in lots of ways) and has involved what I would have considered to be very large VMs not so long ago.  My typical RAC node for testing is usually 4 or 8 vCPUs with 32 GB of RAM, and it turns out these are moderate or small in size.

When the server has 32 cores and 256 GB of RAM, a VM with only 8 vCPU and 32 GB is relatively small.  In fact I'm often running four of them at the same time and still find that performance is great.  Additionally, I'm using vMotion to move these VMs in a matter of minutes from one server to another.

I'm using these 8 vCPU VMs with 32GB of RAM the same way that I used 2 vCPU VMs with 8GB a few years ago.  They are no longer big VMs.  Can't wait to see what we are doing in a few more years.

Tuesday, February 22, 2011

Benchmarking Private and Public Clouds

Earlier today I ran across a test that compared the performance of a private cloud against several public clouds.  The tests were done by CloudHarmony who appears to mostly focus on running tests against public clouds.  They have a variety of tests that seem to be pretty practical and reasonable measuring CPU, disk, memory, encryption, and something referred to as programming language performance (I thought this is what I was given grades for in CS class...).

According to their blog, CloudHarmony agreed to work with KT, a large Korean telecom and do some testing against their private cloud they had recently finished building.  CloudHarmony then compared the results against the many public clouds that they have tested.  In their conclusion they found that the KT private cloud performed very well in comparison to the public clouds.

I find this interesting as it a key aspect of what everybody is going to have to consider as they begin to adopt public clouds.  When does it make sense to use public vs private?  Performance is actually fairly easy to characterize if you can get meaningful tests.  More difficult will be understanding the costs and risks with doing either private or public clouds. I think that for many organizations, it will make sense to use both.  The organizations that get the mix of public and private right will have a competitive advantage, enabling their business to run more efficiently while maintaining agility.

Friday, February 18, 2011

Everybody is Talking About Oracle RAC on vSphere

The momentum and credibility of running Oracle RAC virtualized on VMware vSphere is building and more is being published.  The most recent example is a great whitepaper by EMC that focuses on using their FAST VP Automated Tiering with a virtualized Oracle RAC on vSphere 4.1.

Because the paper is an EMC paper it naturally emphasizes their storage technology.  It's interesting that they decided to use Oracle RAC on vSphere as the stack to highlight their FAST VP.  They could have picked just about anything, but I'm guessing that they used Oracle RAC on vSphere because that's what customers are asking about right now.  This gives two reasons to check it out.  And even if you are a NetApp, EqualLogic or 3Par guy, you might still want to recommend this paper just for the Oracle RAC aspect - or maybe not - but the EMC guys will definitely like it!

I'm not going to get into the details of the paper, but it does include a physcial vs virtual comparison with a very small delta in performance.  Very interesting stuff.

Sunday, February 6, 2011

Favorite Five From Texas

After reading Scott's blog a few weeks ago about his favorite albums, I've been thinking about my own list.  I decided I couldn't do a list of albums and instead of have just decided to list my five favorite Texas musicians.  This list is not in any order.

The Eagles - The Hotel California album is great.  Don Henley is from Texas and I went to the University of North Texas which is the same university that I attended.

Norah Jones - Her distinctive voice and smooth music make it easy to listen to her songs over and over.  We have all of her albums and have them playing in the house often.  Norah Jones also is from Texas and attended UNT.

Jerry Jeff Walker - I have seen Jerry Jeff play all over Texas and I can't wait to see him again this year.  He is most known for Mr. Bojangles, which has been covered by a ton of other artists, but is really at his best on songs like Sangria WineLondon Home Sick Blues, LA Freeway, and Contrary to Ordinary.  Jerry isn't from Texas, but has lived in Austin for over 30 years and much of his music is about Texas.

Stevie Ray Vaughn - The best blues guitarist of all time is from Austin where there is a statue of him near downtown on Lake Ladybird.  His song Texas Flood is a great example of what his music is all about.

Willie Nelson - Willie is one of the greatest song writers and performers over the past 50 years.  I got to meet Willie at a radio station here in Austin about 8 years ago and saw him perform Angel Flying Too Close To The Ground in a very small room.  Willie is simply incredible and has more great songs than I can link to.

You might be able to argue that there are others that deserve to be on the list, there are several more that I wanted to include, but you would have to agree that all of these are pretty good.

Friday, February 4, 2011

Summer Internships at VMware

I attended the career fair at the University of Texas near downtown Austin yesterday.  I was there as part an engineer in the VMware booth to talk to students about opportunities to work at VMware.  We were primarily looking for interns for this coming summer where there are over 100 positions available but also looking for new college graduates as well.  So if you are a student and looking for an internship this summer (or you know a great student candidate), check out our website and submit your resume.

I haven't had the opportunity to attend a career fair in a long time, and I found it really interesting.  It was great to get to talk to so many bright and talented students and think that many of them could end up working at VMware this summer.  After talking with thirty students over the course of a few hours it becomes clear what makes one stand out in comparison to another.

Students that have done significant projects outside of their normal course work or have completed internships that allowed them to gain skills and experience have a big advantage.  Generally these students tend to be seniors or post graduate students, but in a couple of cases I talked to first and second year students that had done some really cool personal projects.

The other aspect that makes somebody stand out is confidence and the ability to speak with certainty about the details of the things that they have done or experienced.  This seems obvious to me after having been in the work force for some time, but looking back on when I was looking for my first internship and job I probably didn't understand how important this is.  Go ahead and speak with confidence about what you do know (without going to far and claiming you know things that you don't - as this will get you in real trouble!).


Wednesday, February 2, 2011

Hitting Multiple Targets Like Bruce Lee with DVD Store 2.1

Bruce Lee was so fast that he could deliver punches and kicks to many bad guys at the same time.  As a matter of fact he would have been bored if he was only hitting one guy at a time.

DVD Store 2.1 now has a driver program that can deliver requests to multiple databases at the same time.  This allows for a single driver program to push load against multiple DVD Store databases that are running on different hosts.  The most common reason to this is needed was to be able to run load against a number of virtual machines all at the same time.  Prior to this new version, we ran load against multiple VMs by having multiple driver programs running.  This worked fine, but it required some scripting to synchronize starting and it also required some work after the run was over to get the total orders and average response time across all the VMs.

The new "Bruce Lee" enabled driver program runs against multiple databases and reports the stats on a per target basis as well as totals.  This makes it much easier to do tests against multiple DVD Store databases and get the summarized results.

The multiple targets are specified using the same parameter that was used for single targets, but you can now specify more than one by listing them with semicolons.  An example looks like this:

ds2oracledriver.exe --db_size=20GB --n_threads=4 --target=host1;host2;host3;host4

One interesting point is the number of threads that will be run is specified on a per target basis.  So in the above example 4 threads will be run against each host, resulting in 16 threads total.

The new DVD Store 2.1 has many new enhancements, including things like custom size databases, that I'm writing about in this series of blogs.  More to come in the following weeks.