[Vm-dev] Compiling squeak-vm for Linux 64bit

John M McIntosh johnmci at smalltalkconsulting.com
Tue Mar 17 17:47:23 UTC 2009

Someone might want to look into if the project read is using the  
multibyte streams in text mode. If so in my past experience with  
Sophie is that a read requires reading
byte by byte, which actually ends up reading a byte by byte from the  
file system. Although this is *fast* (a relative term) because stdio  
caches data for reading,
perhaps the 32 to 64 thunking between the C code and the 32/64 stdio  
is intensive.

For Sophie and other products we would suck the entire file into a  
read//write internal stream, then pass that to the multibyte stream  

For writing the pattern is even worse because the multi-byte logic in  
text mode writes one byte at a time. Write 5 mb and it's 5 million  
system calls and the overhead is quite large. For Sophie we built a  
caching output stream that would stream out to memory, then at close  
time flush the contents to the file stream.

PS you can see this on unix systems by looking at system calls (or the  

On 17-Mar-09, at 5:38 AM, José L. Redrejo Rodríguez wrote:
> It's a total subjetive impression: big projects take more time to load
> in this environment, than in a pure 32 bits environment.

John M. McIntosh <johnmci at smalltalkconsulting.com>
Corporate Smalltalk Consulting Ltd.  http://www.smalltalkconsulting.com

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