I have a process that continually runs something in a loop. It is opening forms, processing things on them, and then closing them. After a while, the process starts getting some errors and eventually crashes.

Looking in Task Manager, I noticed that the process is hitting the limit of 10,000 GDI objects. This process must have a GDI object leak somewhere.

I downloaded GDIView.exe and noticed that the “All GDI” column keeps increasing over time, but the numbers of the listed types of GDI objects are reasonable and not increasing.

For example, see the screenshot below. GDIView.exe is showing 1,782 “Other GDI” objects. The rest of the columns show 4 Bitmap, 1 Region, and 0 other types of objects:

I downloaded a script “DumpGdi.txt” to help WinDbg show GDI object counts in a memory dump. The list only counts less than 100 GDI objects at any given time despite Task Manager and GDIView.exe showing a large number of GDI objects.

What are the GDI objects that are accumulating in the “All GDI” column in GDIView.exe? I would like to know what is leaking, so I can know what to look for in my code.

Windows Task Manager shows the same high of GDI objects, too.

I do not see any managed object memory leaks. If there were managed objects, I could see them if I run a !DumpObj -type command, and I could use !GCRoot to find why they are being leaked. I would also expect to see a large number of Icon, Font, and possibly Bitmap objects, but these types do not appear to be a problem in the GDIView.exe output.