lighttpd and slow pages

Question

We have a long and slow cgi-script. Hypothetical example script:

#!/bin/sh

echo "<p>1<p/>"
sleep 1
echo "<p>2<p/>"
sleep 1
echo "<p>3<p/>"
sleep 1
echo "<p>4<p/>"

With lighttpd v1.4.35 it worked fine:

Begin of the page was visible in a browser immediately, and rest of the page was slowly updated to the browser.

After update to lighttpd v1.4.51, those long-and-slow pages are transmitted from lighttpd to the browser when the page is completely created. That causes ugly delay:

When a user tries to enter to that kind of slow page. Nothing happens for several seconds, and finally after waiting the page appears.

Is there some configuration option or trick to force lighttpd v1.4.51 to stream a page content to browser when a CGI-script is still running?

Answer 1

The following configuration line in lighttpd.conf seems to give the wanted result:

server.stream-response-body = 2

More information in documentation of lighttpd.