[plt-scheme] Typed-Scheme Memory Issues

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Wed Apr 8 02:26:32 EDT 2009

It might still be worth examining why TS uses so much memory.
Type checking should be linear in space in the source code,
though I suspect that this is not quite true when you use
unions and other commutative/associative things that require
extra work. But, type checking 3000 lines of code should
never use 2GB. -- Matthias

On Apr 7, 2009, at 3:51 PM, Sam TH wrote:

> That's certainly quite a lot of memory use - and a lot of Typed  
> Scheme code!
> I don't know why it should take that much memory, but the one thing I
> do recommend is compiling your files to byte code.  DrScheme does this
> automatically in some cases, and you can do it manually with 'mzc -k'.
>  Once the file is compiled, typechecking is complete, and subsequent
> uses of that file should be much faster.  For example, if you have
> files A.ss, B.ss and C.ss, each of which depends on the preceding,
> then if you are changing C.ss a lot, then
> % mzc -k A.ss B.ss
> will likely improve your speed/memory issues.
> If that doesn't help, let me know, and I'll try to see if there's
> something in particular that's going wrong while typechecking your
> code.
> sam th
> On Tue, Apr 7, 2009 at 3:45 PM, Paulo J. Matos <pocmatos at gmail.com>  
> wrote:
>> Hi,
>> I have been using typed-scheme for a bit now and my code base in  
>> typed
>> scheme is now involving [only] 4 modules with a total of 3000 loc.
>> Unfortunately, though things have been pretty slow for me lately  
>> since
>> evaluating the main module of my project takes something in the order
>> of minutes requesting over 2Gb of memory. Since I [only] have 2 Gb of
>> memory, swapping starts and things get even slower.
>> About this I don't know what to do but it needs to be improved. I  
>> have
>> taken a few screenshots so you can check how the memory evolves while
>> drscheme is interpreting a typed-scheme module [svn 14441]:
>> Idle:
>> Values http://users.ecs.soton.ac.uk/pocm06r/values_idle.png
>> Graph http://users.ecs.soton.ac.uk/pocm06r/graph_idle.png
>> On Load:
>> Values http://users.ecs.soton.ac.uk/pocm06r/values_load.png
>> Graph http://users.ecs.soton.ac.uk/pocm06r/graph_load.png
>> Note that I have mostly nothing else running besides the gnome
>> desktop... I sincerely don't know what to do. I hope this is just a
>> bug regarding memory handling and can be easily fixed.
>> If I can provide more info on this so it can be analyzed please  
>> let me know.
>> Cheers,
>> --
>> Paulo Jorge Matos - pocmatos at gmail.com
>> Webpage: http://www.personal.soton.ac.uk/pocm
>> _________________________________________________
>>  For list-related administrative tasks:
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> -- 
> sam th
> samth at ccs.neu.edu
> _________________________________________________
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