> The problem is, the apache threads associated with these curl calls do
> not disappear - but stick around in "sending reply" mode - as reported
> by the apache 2.0.48 extended status stats.
>
> I know the URLs are actually returning and not timing out because the
> graphs would reveal timeouts.
> I am puzzled why curl is exhibiting this behaviour with apache.
> Eventually I have to HUP the apache server to clear the threads.

HTTP/1.1 will keep the connection alive for a while.

The last thing in my curl --trace log to an Apache2 server is:
        == Info: Connection #0 left intact
Neither side is sending Connection: close, so as I understand it the
TCP connection stays open, as per
    http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.10

Eventually the server should close the connection depending on your
keepalive settings in httpd.conf.

However, if this is the explanation then it seems that Apache2 is
misreporting the thread's status; I'm not familiar its extended status
stats.

You could try using a command like truss or ktrace to see what the
Apache thread is doing.

I hope this isn't completely off-the-mark.
It sounds like a cool use of curl and cacti!

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