stack vs workspace for pcre and others #1576

Nils Goroll slink at
Tue Sep 2 21:34:53 CEST 2014

On 02/09/14 21:24, Nils Goroll wrote:
> Or, alternatively, realize that we need a larg-ish stack anyway

For all those who have not yet read pcrestack(3):

       As a very rough rule of thumb, you should reckon on about 500 bytes per
       recursion. Thus, if you want to limit your stack  usage  to
       8Mb, you should set the limit at 16000 recursions. A 64Mb stack, on the
       other hand, can support around 128000 recursions.

pcre_match_limit_recursion 10000 (default)
thread_pool_stack          48k [bytes] (default)

So these obviously do not fit at all.

We we opt for keeping pcre on the stack, we should consider to auto-tune either
to sensible values.


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