PushOK in combination with svn takes much time for SccPopulateList

When i call SccPopulateList for a svn module the call takes really much
time. I can see that PushOK creates a temp folder under %TEMP%/UDSAA63 for
example and stores all files from the whole repository. After this is
finished the content of the folder is removed again. The callback for
SccPopulateList contains only the files under the given svn module as
intended.
My questions are:
Why the whole repository is worked even i want only the files under a given
svn module?
Can i change this behaviour, because the repository is very large and i
want only a part of it given by the svn module?

The current behaviour is not acceptable, because the call can take more
than a hour only for getting a list of files of a svn module.