cperl + isearch + font-lock-multiline sometimes very slow

[Klaus Zeitler]

Since approx. last week isearch slows sometimes down to crawling speed in
cperl files. Looking at top I see that emacs then needs around 30% CPU and
when I stop isearch, for the next minute emacs eats up even more CPU before
going back to normal behavior.
This behavior disappeared when I turned off font-lock. Therefore I checked
my font-lock settings and found out that setting font-lock-multiline to nil
also helped. So I'm guessing it has something to do with font-lock or
jit-lock. How should I proceed now to investigate this further?

Thanks

Klaus

-- 
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|  Klaus Zeitler      Lucent Technologies  |
|  Email:             address@hidden  |
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One Page Principle:  A specification that will not fit on one
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