[erlang-questions] Dangers of generating a large erlang module
Erik Søe Sørensen
Sun Sep 29 19:36:02 CEST 2013
Core Erlang is an intermediate representation in the Erlang compiler - but
also (afaik) a fairly well-defined/public one and one that is stable.
I don't think you'll find much in the vein of tutorials. Try getting erlc
to output the intermediate format, though, for a small program similar to
what you'll be using it for.
Den 29/09/2013 19.20 skrev "Ivan uemlianin" <>:
> Thanks! I think I'll try and head in that direction. I've had a few goes
> at other methods (db lookup etc) and they're much slower than this "dynamic
> hardcoding"). I'll sniff around for Core Erlang tutorials.
> Best wishes
> festina lente
> On 29 Sep 2013, at 17:48, Erik Søe Sørensen <> wrote:
> A thing which I discovered recently (in connection with mochiglobal) is
> that compiling code containing large binaries, or large amounts of
> binaries, is quite memory-intensive. As I recall it, the numbers were ~64
> bytes of RAM per byte in a binary metal; twice as much if on a 64 bit
> Which means that if you want to compile modules containing (in sum)
> multimegabyte binaries, doing so from Erlang source or from full Erlang AST
> is a no-go. Iirc, it is feasible if starting from Core Erlang.
> Den 29/09/2013 12.50 skrev "Ivan Uemlianin" <>:
>> Dear Anthony
>> Thanks for your comment.
>> Yes, that's exactly what the generated module is doing. The generated
>> module has a single function with many clauses like this:
>> f(<<"trigger", Rest/binary) -> ...
>> This is why (as far as I can work out) the generated code has to be so
>> I prefer the idea of generating and loading code to, say, updating a
>> database table, because it seems faster and less likely to lead to
>> Best wishes
>> On 29/09/2013 11:38, Anthony Ramine wrote:
>>> Hello Ivan,
>>> Out of curiosity, what does it look like?
>>> Pattern matching on literal values in Erlang is done with a binary
>>> search over the sorted list of patterns, I am not sure this would play well
>>> with your use case even if the compilation didn't bring the VM down.
>>> Le 29 sept. 2013 à 11:29, Ivan Uemlianin a écrit :
>>> All goes well on small test files, but the files I want to use IRL are
>>>> relatively large --- around 120,000 lines.
>> Ivan A. Uemlianin PhD
>> Speech Technology Research and Development
>> festina lente
>> erlang-questions mailing list
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