Re: Erlang challenge

[Ulf Wiger <address@hidden>]

On Sat, 7 Jun 2003, Steve Dekorte wrote:

>
>On Saturday, June 7, 2003, at 09:35 AM, Anton van Straaten wrote:
>
>> Don't know about a list.  There are some details of the test, showing a
>> comparison between Erlang and Java, with source code for both
>> languages,
>> here:
>> http://www.sics.se/~joe/ericsson/du98024.html
>
>Looks like Erlang only has a 1K stack size. Does it
>dynamically adjust this as more stack space is needed, or
>is it set dangerously low in order to get good results for
>this particular test?

I never saw this question being answered. Erlang allocates
a combined stack and heap, and increases the heap/stack if
garbage collection cannot free enough memory.

It is possible to set a minimum heap size for each process
being spawned. This can be used to completely avoid
garbage collection for short lived jobs, or to otherwise
tune the memory management characteristics of a process.
This sort of tuning would be done based on GC traces,
showing exactly when GC kicks in (timestamp + current
function), how the heap changed, and how much data was
freed. This is one of the many things Erlang's dynamic
tracing support can help you with.

I'm quite sure Joe did not fiddle with the heap sizes.
I reproduced his results with my own benchmark program
and default settings.

/Uffe
-- 
Ulf Wiger, Senior Specialist,
   / / /   Architecture & Design of Carrier-Class Software
  / / /    Strategic Product & System Management
 / / /     Ericsson AB, Connectivity and Control Nodes