This excessive use usally causes a "Panic: Insufficient Memory" erroe message.
The issue seems to be a known, unhandled exception within the Notes memory manager (SPR# JFAA5PXHR4). An official fix has been deferred to a later codestream (maybe ND7? I doubt it, though - usually support tells you if it's addressed in an upcoming major release) Essentially Notes' garbage cleanup isn't keeping up with the allocations being made. A workaround is listed, however. The following Notes.INI settings:
httpusenotesmemory=0 inotesusenotesmemory=0
...will have the HTTP task use the operating system's memory allocation and de-allocation routines. While this means debug information won't be available on the stack in the event of a crash it does mean better memory usage and slightly better performance.