So here's the scoop:

The company where I work has a few GUI-based Java programs that runs crazy fast in Windows XP. Upon upgrading 6 machines to Windows 7 (and yes, we definitely exceed the requirements to run Windows 7 on our machines), these Java programs run significantly slower (For example: logging into takes 5 seconds to load the program in XP. It now takes a minute in Windows 7). We're running Java 6 version 18. I've been researching this for hours and can't seem to figure out why Java is so terrible on windows 7. Anyone hear of anything coming out of the Sun/Oracle or Microsoft camps (or elsewhere) in regards to this issue? I read somewhere that switching the compatibility mode for java.exe to Windows Vista or XP would solve the trick, but this solution didn't work for us.

I will also note that our .NET applications (and ever other application for that matter.. Office 2007, Firefox, etc) run just fine.

If there's a similar thread to this, I can't find it.

Thanks in advance for any help that can be provided!

Recommended Answers

All 12 Replies

Ah... I'll add one more note here that I left out:

When I say running slower, I mean that java seems like it is being a process hog and driving the CPU Usage up to 60-100% when you are doing nothing with the program. I also know Aero is enabled on the machine. Anyone know if this throws off java? Seems like all other programs work just fine.

have you made sure you're running a 64 bit version on 64 bit Windows (if relevant)?
Might make a difference.

I've not heard of performance problems of Java applications running on W7 from colleagues using the OS (and we're a Java heavy development shop) so it's unlikely to be something generic to the combination Java/W7 (which of course doesn't exclude the possibility that there's some combination of applications/JVMs/OS variants that can be problematic).

You might try updating to 6u19 and see if that makes a difference, but it may not, there are some applications that just don't perform well on a 6.0 JVM (especially some older applications that make use of specific workarounds for bugs in 1.4 and earlier JVMs).

I'm running 64-bit Java 6u18 on Windows7 and it runs great. No performance issues at all that I have seen, and our app is extremely computationally intensive.

I build and test a Java application on different versions of windows, I have not come across any specific Win7 performance issues. But one thing that does matter is administrative rights, check your UAC rules, if your application does some role specific activity it could lead to some pointers to the issue.

Hi c_shaft05,

I am happy to finally find someone who seems to have similar problems with the combination Windows 7 and JAVA.

We also have client/server JAVA application running on our machines. Ever since we upgraded a couple of machines to from XP to Windows 7 the application's swing client starts up very slow. It tries to connect to a server process on the same machine at that time via CORBA. So my fist shot was to see if any network settings were at fault. So far I have not found any settings consistently changing the observed behavior. The only thing which helps to resolve the performance degradation is to pull the network cable which is not a viable solution for client/server applications ;-).

Could you provide any information about what you have tried to resolve your problem so far? Maybe a comparison of environments would also help to "digg up" the solution. We have found at least one XP machine which shows similar behavior. The application is close to unusable on that machine until I unplug the network cable...

That sounds suspiciously like you're having some problems relating to the built-in firewall functionality of Windows causing some port redirects of blocks.

Check there, see if you have to open up something for things to work as expected.

I tried turning off the firewall for all profiles. Unfortunately this did not fix the slow communication.

Any other suggestions how I could further diagnose this problem?


I recently installed Windows 7 Professional 64bit on my computer (leaving Windows XP Professional 32bit on another partition).
And I actually now have similar performance problems, and so far I've been unable to fix them.

We're developing a web application that we test running locally on a Tomcat app server (it's a portlet based application running within a Liferay portlet container to be exact). The applicaition is noticibly slower running on Windows 7.

I haven't done any exact tests, but my impression is that pages load on average about 2x longer than on the same machine running Win XP. Sometimes it takes longer, sometimes they load a bit faster.

I've also tried disabling the firewall/anitvirus (using PC Tools and AVG on both the XP and 7), running the application on a 32bit and 64bit Java virtual machine and nothing would make any noticible difference. I'm using the latest Java 1.6 update 20, but I've also tried one previous version (update 10).

Using the Windows XP compatibility mode didn't help either.

I even looked for similar problems with other slow running software on Win7 and found these problems with Chrome which seem to be related to LAN settings:

I tired applying the solution from this thread, but again, it didn't work.

Anyways, I'd also be thankful for any suggestions/help. For now I'm back to using Win XP...

Ok, I tried the suggestions from ender1975. Unfortunately that didn't help in my case either.

My impression is that something is seriously messing with the network traffic on my machine when I start the JAVA application. So I tried playing around with the network properties for the net device I am using. If I turn off the Deterministic Network Enhancer things get better. However as far as I have read this is not part of Windows but installed with CISCO VPN solutions.

Maybe this helps someone else. I have yet to find an answer to why the DNE would be causing this. On Windows XP I had this also installed and there I had no problems.

Sorry for not posting it sooner, but I actually found out yesterday what was causing this problem for me.

It was the firewall (PC Tools).

Before when I was trying different things, I just disabled it and that didn't help. But sort of as a last resort, I completely uninstalled it, and what do you know, the problem was gone. So, at least in my case it seems like it clearly was a PC Tools on Win7 problem (possibly PC Tools vs Java problem? I definitely had no problem with other network traffic).

I am now running the Comodo Firewall and things are fine.

I only have the Windows 7 system firewall running and MS Forefront Security. Tried turning off all of these with no luck.

Ok, we ended up figuring out our issue.

Even though our machines definitely met the requirements, we had to upgrade the bios firmware of our machines (These machines are 2 years old with firmware not updated to handle windows vista/windows 7).

After a bios upgrade, everything flies without fail.

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, learning, and sharing knowledge.