[erlang-questions] HiPE and large number of string cases

Peter Wang <>
Mon Jul 2 10:11:02 CEST 2007

On 2007-07-02, Kostis Sagonas <> wrote:
>  I cannot reproduce your findings with the latest OTP release (R11B-5). I've 
>  created two such functions, one with 500+1 cases and one with 1000+1 cases, 
>  and the times I get indeed show that there is a non-linear component 
>  somewhere in the native code compiler, but it is nowhere as bad as you 
>  describe.
>  2> timer:tc(hipe, c, [{t,f500,1}]).
>  {7211870,{ok,{t,f500,1}}}
>  3> timer:tc(hipe, c, [{t,f1000,1}]).
>  {21001894,{ok,{t,f1000,1}}}
>  For me, native code compilation on an x86 running Linux takes about 7.2 secs 
>  for 500 cases and 21 secs for 1000.  With optimization level o1 these times 
>  are smaller.

Hmm, I can confirm that with an artificial test case using strings like
"a1", "a2, etc.  Perhaps it has to do with the strings themselves?

>  Which OTP version are you using?  What platform is this?

I am using R11R-3 on Linux/x86_64.

>  If you are not using R11B-5, can you try with that and tell us what's 
>  happening.

I will do that.  If the problem persists, would you mind if I sent you
the test case?


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