> In my case, it appears Apache selects the chunked encoding automagically 
> when the size of the page goes over a certain size.  Apache doesn't seem 
> to set the smaller pages to the chunked encoding (even though they are 
> gzipped).

No, this was wrong. Mod_file_cache was tricking me (again).  Apache appears to 
set the Transfer-Encoding to chunked when the page is
actively being gzipped and the final gzip file is bigger than 
DeflateBufferSize.  But if the page was gzipped and stored on disk by
mod_file_cache (like we do) it means Apache is merely spooling the file off the 
disk (it doesn't put it though gzip a second time)
and chunked encoding will *not* be used.

Now I'm going to speculate that a chunked gzip web page is going to be slower 
than the unchunked equivalent because the browser have
to spend "some amount" of time putting the chunked version back together.  But 
I'm wrong again.  We just tested this and the timing
of Firefox 4's load event didn't increase with the number of chunks.  Even 
setting DeflateBufferSize down to 500 bytes on a 40K page
didn't produce consistent differences.

The one consistent metric was that with chunking on (DeflateBufferSize smaller 
than total compressed page size), Apache was able to
get the first byte to the web browser about 75ms faster but again, the faster 
response time didn't translate into a consistently
faster rendering of the page by the browser.  

This testing needs further study before it's taken as gospel.  We only ran 
about 4 tests per DeflateBufferSize.


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