Performance analysis of OpenOffice and MS Office

In my last blog, where I did a high-level technical evaluation of Microsoft Office 2003 and OpenOffice.org 2.0, I showed that OpenOffice was a memory and resource hog.  Contrary to popular belief (among Open Source advocates), Microsoft Office came out very lean and fast while OpenOffice.org Office Suite was just the opposite.  Some couldn't accept the numbers and complained that the Task Manager numbers may be inaccurate and hiding memory usage.  They demanded more proof, so here it is.

To get more granular and detailed memory and processor consumption data, I downloaded a copy of Process Explorer from SysInternals and used it to gather a wide range of Data.

Here is a comparison of memory and CPU usage between Microsoft and OpenOffice.org office applications.  This is with just the bare application and blank data file loaded.  Note that SOffice.exe resource utilization was very minimal and is probably just a basic launcher.  To keep things simple, only SOffice.bin was counted against OpenOffice.org.

From this table, we can see that OpenOffice.org is indeed a memory and CPU hog.  It is literally taking up about 10 times the processing time and memory to just load the application itself along with a blank file.  It doesn't matter how fast the CPU is, 10 times is 10 times and OpenOffice is simply bloated.  If that doesn't convince you, look what happens when we try to load our large 16-sheet sample.

Here is a comparison with the standard 16-sheet SXC and XML sample file I've been using.  The sample is in compressed XML format because it is smaller and easier for you to download.  You'll have to convert the XML file to XLS and the SXC file to ODS to run the following test yourself.

Even when dealing with what is essentially the same data, OpenOffice Calc uses up 211 MBs of private unsharable memory while Excel uses up 34 MBs of private unsharable memory.  The fact that OpenOffice.org Calc takes about 100 times the CPU time explains the kind of drastic results we were getting where Excel could open a file in 2 seconds while Calc would take almost 3 minutes.  Most of that massive speed difference is due to XML being very processor intensive, but Microsoft still handles its own XML files about 7 times faster than OpenOffice.org handles OpenDocument ODS format and uses far less memory than OpenOffice.org.

Now to be fair, OpenOffice.org is free and is cross platform, but does this really matter to the 90% of the users in the world who only use Windows?  Does this change the fact that OpenOffice.org is a CPU and Memory hog?  Microsoft Office Professional on the other hand costs about $240 when bundled with hardware or if you look for OEM pricing.  I'll leave it up to you the reader to determine if your money is worth more than your time.

Preview blogs in this series on OpenOffice.org versus MS Office

• OpenOffice.org 2.0 is here, but is it a pig?
• In defense of OpenOffice.org
• Microsoft Office versus Open Office shootout