Here are a few performance tips when using VisualAge for Java.  I'll add more as I hear them...

Defragment your drive often!

The VisualAge for Java repository is rather large (usually over 20MB, much larger for Enterprise edition) and can fragment very quickly.  By defragmenting your drive often (I defrag every day) you can speed up access to the repository.

IMHO, this is the number one culprit of performance problems. Machines are getting so fast that disk access is a significant bottleneck. Any time you hit the disk, whether it is to access data (like VisualAge retrieving/saving source) or page virtual memory, you take a performance hit.

If your disk is badly fragmented, as is usually the case with Windoze NT (it doesn't come with a defragmentation tool), the disk access time increases significantly.

If you're using OS/2, this is not an issue with HPFS drives! HPFS somehow prevents fragmentation.

If you're using Windoze 95/98, use the defragmenter that comes with the operating system (you can access it from the "tools" page of a disk's property sheet, or from the "System Tools" submenu (somewhere off the start menu).

If you're using Windoze NT, it does not come with a defragmentation tool. However, you can get a free tool at - look for "Diskeeper Lite". You need to start it manually for each drive, but it's free.

Other NT defragmentation tools are available at

I use both tools - diskeeper to reduce directory fragments and perfect disk for general defrag. If you only buy one, I'd recommend diskeeper for the directory consolidation.

Delete unneeded things from your repository!

Smaller repositories can mean better access times for the data you're looking for.   See Deleting from the Repository for information on cleaning out things you no longer need.

Delete unneeded things from your Workspace!

Any time you save a method, VisualAge checks dependencies in your Workspace and recompiles anything that needs recompilation.  The larger the workspace, the slower this process can become.  If you've got code in your workspace that you don't use (like that copy of Swing you imported to look at but aren't using in your code), do the following:

Try a Different Operating System!

Some platforms use resources more efficiently than others.

Windoze versus OS/2

From my personal "testing" (mainly playing around to see how things are working in different environments) I've seen OS/2 consume fewer resources than Windoze 95 or Windoze NT.  (This is on the order of 20-30MB less memory used when running the operating system and VisualAge, doing the same activities.)  If you have and like OS/2, use it for running VisualAge for Java.  (Note that the interchange format is compatible between the Windoze and OS/2 versions of VisualAge for Java.)   The OS/2 version of VisualAge for Java acts almost identically to the one in Windoze.  The biggest difference is that in OS/2 you drag with the right mouse button, whereas you'd use the left mouse button to drag in Windoze.

Windoze NT vs Windoze 95 vs Windoze 98

I have heard reports in some newsgroups that VisualAge for Java performs better on Windoze 95 than on Windoze NT.  NT is more of a resource hog than 95, so this might make some sense.  However, a bigger difference might be attributed to using a FAT partition to hold VisualAge instead of an NTFS one.  (NTFS has much more to do, especially with regard to security, which slows it down.)

Windoze 98 is a major resource hog - Windoze 95 runs VisualAge much better.

Others have suggested that is you use VisualAge for Java on an NTFS partition, try compressing the repository (\IBMVJava\ide\repository\ivj.dat) and workspace (\IBMVJava\ide\program\ide.icx) files.  I haven't tried this so I cannot comment on it.

Get More Memory!

The biggest and least expensive way to gain VisualAge performance is to add more RAM.   As computers get faster, the speed of file I/O becomes more of a gating factor.   If you don't have enough RAM to run the program, data must be swapped out to your disk, and that can be very slow compared to other operations on your computer.

Memory right now is incredibly cheap, and it seems that the prices keep coming down.  You can get an additional 32MB RAM for under $100 (US), depending on where you shop (check to compare prices).  (I remember paying $170 for a 1MB RAM upgrade for my Amiga 2000 several years back...)  By adding more memory, getting your system up to at least 64MB, you'll encounter less swapping and much improved performance.

64 MB RAM seems "ok" for VisualAge, but more can't hurt, especially if you're like me, running VisualAge for Java, a browser, a mail program, a paint program, a word processor a text editor at the same time.

Overall - I recommend 128MB RAM for best performance - it's rare that you only run VisualAge...

Use a Fast-Access Hard Drive

If you have a SCSI hard drive on your computer, that makes a much faster home for VisualAge for Java, as well as your virtual memory swap file.  (Note on NT: NT is very disk bound.  It's constantly checking for something on your hard drive.  If you have more than one physical hard drive (as opposed to more than one partition on a single hard drive) try to put your swap file on the hard drive that is less used (usually the one that doesn't contain the NT operating system.)  This will allow your swapfile to be accessed at the same time as other files on the other drive, resulting in less head movement on the drive.

Otherwise, get the fastest access-time drive you can. VisualAge is very disk-intensive, and access-speed can make a significant difference in performance.

Get a Newer Computer!

If you are trying to run VisualAge for Java on a 33MHz 486 with 8MB RAM, forget it...

A single tool is not a good reason to buy a new computer, IMHO.  (Unless of course your entire job hinges on that tool...)  However, if you're finding that many of your applications are not performing well, you may want to look at buying a newer computer...