cperl-speed is a variable defined in `cperl-mode.el'.
Its value is

This is an incomplete compendium of what is available in other parts
of CPerl documentation. (Please inform me if I skept anything.)

There is a perception that CPerl is slower than alternatives. This part
of documentation is designed to overcome this misconception.

*By default* CPerl tries to enable the most comfortable settings.
From most points of view, correctly working package is infinitely more
comfortable than a non-correctly working one, thus by default CPerl
prefers correctness over speed. Below is the guide how to change
settings if your preferences are different.

A) Speed of loading the file. When loading file, CPerl may perform a
scan which indicates places which cannot be parsed by primitive Emacs
syntax-parsing routines, and marks them up so that either

A1) CPerl may work around these deficiencies (for big chunks, mostly
PODs and HERE-documents), or
A2) On capable Emaxen CPerl will use improved syntax-handling
which reads mark-up hints directly.

The scan in case A2 is much more comprehensive, thus may be slower.

User can disable syntax-engine-helping scan of A2 by setting
variable to nil (if it is set to t).

One can disable the scan altogether (both A1 and A2) by setting
to nil.

B) Speed of editing operations.

One can add a (minor) speedup to editing operations by setting
variable to nil (if it is set to t). This will disable
syntax-engine-helping scan, thus will make many more Perl
constructs be wrongly recognized by CPerl, thus may lead to
wrongly matched parentheses, wrong indentation, etc.

One can unset `cperl-syntaxify-unwind'. This might speed up editing
of, say, long POD sections.