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From "Richard Esmond" <>
Subject Re: Volunteer: File Upload/ Multipart form handling
Date Tue, 03 Oct 2000 17:27:46 GMT
Some unsolicited advice from a lurker...

The issue mentioned about file uploads to memory being a problem for large 
files is easily managed such that you can 'have your cake and eat it too'.

If you arrange for the 'memory' to be a memory mapped file, the performance 
of the upload is maximized as well as the 'forward buffering' benifits 
without significant usage of physical memory.  The cache manager of NT does 
well here as do most 'Unix' implementations of memory to file mapping API's.

I will add this to my list to investigate how the VM would handle this 
process.  If the VM is unable to utilize a memory to file mapping then you 
could get yourself into trouble with a memory targeted solution that relied 
on typical 'virtual memory' swapping to disk.  You are adding a significant 
overhead to recopy the file from 'vm-on-disk' to file-destination.  With a 
pre-specified memory mapped file, you would simply close and rename when 

I have done very similar things before (in C), and memory mapped files 
proved very clean and fast.  I will look into this, and I would encourage 
you to do the same.

Sorry for any intrusion,
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