How much does your AV product impact performance?

vista_wallpaper This time last month I pitted Windows Vista against several desktop operating systems.  One of the longer tests I ran was a file copy test to see who was the I/O king.  Over the past few days I've run some additional tests.

One of the tests I ran was the same copy of 42GB of data from an external SATA drive to the internal PATA drive of my Compaq Evo n620c.  The n620c was running Windows XP SP3 at the time and finished the copy in 30 minutes.  Huh?  Now how is it that my oldest machine turned in a smoking time?  Nearly one of the best.

Of course I slapped my head when I noticed I had not installed CA eTrust.  It's unusual for me to have a machine that doesn't have eTrust installed.  This is especially true if the machine is ever going to be used with a VPN connection to our corporate network, or any network outside my homelan for that matter.

So how much overhead does your AV product add to a sustained bulk copy?  

Lots.  In fact, it really surprises me that the T61p with Windows Vista x64 turned in the top scores and the MacBook Pro didn't lay waste to all comers.  The T61p had eTrust installed during it's testing and the Mac didn't.  The Mac doesn't need AV, right?

So how much overhead does an AV product add to the time it takes to copy data?  Well it really depends on the data mix, the direction of the copy or move (reads or writes), and other factors like the operating system architecture.  In this case, the copy from an external drive to the internal drive of the Evo n620c took twice as long when AV was installed. WOW.

Which brings me to another point that is seldom raised during 64 bit discussions. Everyone knows that in order to go above 4GB of memory use, you need to move from a 32 bit address space to a 64 bit address space.  And everyone understands the implications of more memory for things like virtualization, large cache areas for database performance, etc.  But rarely do I see a discussion of I/O performance when people talk about the move to the 64 bit world.  At least not in the desktop discussions.  But the performance improvements are there.  I'll see if I can dig up some benchmarks.

In the meantime, the ThinkPad T61p with Windows Vista x64 is still king.  King over OS X.  King over Windows XP.  This is especially true when you consider my OS X machine had no anti virus product installed.

If you are wondering about the Compaq Evo, it has been upgraded to Windows Vista Enterprise x86.  I'm sure a lot of you consider that a downgrade.  But I'm going to run it for a while to see how it does.  It has a measly 1GB of RAM, an ancient ATI Mobility Radeon 7500 video card, but a smoking 100GB 7200rpm Hitachi PATA drive.  Wanna guess what the Windows Vista WINSAT index score value is?  Here's a clue from 2006.