The parser ebrowse normally writes regular expressions to its output file that help the Lisp part of Ebrowse to find functions, variables etc. in their source files.
You can instruct ebrowse to omit these regular expressions by calling it with the command line switch ‘--no-regexps’.
When you do this, the Lisp part of Ebrowse tries to guess, from member or class names, suitable regular expressions to locate that class or member in source files. This works fine in most cases, but the automatic generation of regular expressions can be too weak if unusual coding styles are used.
The smaller the minimum length, the higher the probability that Ebrowse will find a wrong match. The larger the value, the larger the output file and therefore the memory consumption once the file is read from Emacs.
The larger the maximum length, the higher the probability that the browser will find a correct match, but the larger the value the larger the output file and therefore the memory consumption once the data is read. As a second effect, the larger the regular expression, the higher the probability that it will no longer match after editing the file.