Re: [ssax-sxml] ssax thread-safe? example

[Bruce B. <ba...@en...>]

That was it. Thanks so much for pointing this out -- the words 'static 
buffer' kind of stand out, don't they? Works like a champ now.

Joerg F. Wittenberger wrote:
> Hello Bruce,
> 
> Disclaimer: I'm _not_ activily using the SSAX parser.  So please
> forvige me, if I'm citeing old code here.
> 
> Bruce Butterfield <ba...@en...> writes:
> 
> 
>> filename="threadtest.ss"
>>
>>(require (lib "thread.ss")
>>         (lib "date.ss")
>>         (lib "ssax.ss" "ssax")
>>         (lib "myenv.ss" "ssax")
>>         (lib "input-parse.ss" "ssax")
> 
> 
>>From input-parse.scm
> 
> ; Procedure input-parse:init-buffer
> ; returns an initial buffer for next-token* procedures.
> ; The input-parse:init-buffer may allocate a new buffer per each invocation:
> ;	(define (input-parse:init-buffer) (make-string 32))
> ; Size 32 turns out to be fairly good, on average.
> ; That policy is good only when a Scheme system is multi-threaded with
> ; preemptive scheduling, or when a Scheme system supports shared substrings.
> ; In all the other cases, it's better for input-parse:init-buffer to
> ; return the same static buffer. next-token* functions return a copy
> ; (a substring) of accumulated data, so the same buffer can be reused.
> ; We shouldn't worry about new token being too large: next-token will use
> ; a larger buffer automatically. Still, the best size for the static buffer
> ; is to allow most of the tokens to fit in.
> ; Using a static buffer _dramatically_ reduces the amount of produced garbage
> ; (e.g., during XML parsing).
> (define input-parse:init-buffer
>   (let ((buffer (make-string 512)))
>     (lambda () buffer)))
> 
> ...
> 
> So you might want to make sure that there is something alon the lines
> of:
> 
> (define input-parse:init-buffer
>   (lambda () (make-string 512)))
> 
> in your code.
> 
> best regards
> 
> /J?rg
>