Date: Sun, 20 Apr 1997 11:50:55 +0100 (BST)
From: Paul Sutton <paul@ukweb.com>
To: new-httpd@apache.org
Subject: Re: graceful restarts, take 3
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I would love to see graceful restarts implemented (as a patch for 1.2).
And a graceful die would be nice too -- and the moment it is a pain having
to wait for the server to be quiet before killing it to change versions. 

On Sat, 19 Apr 1997, Dean Gaudet wrote:
> I've also made the child_main code more aggressive about dying on USR1... 
> in particular I wasn't happy with the old servers sitting in KEEPALIVE
> after a USR1.  But the sacrifice here is that it's possible for us to have
> read the request before we die, and we'll die without telling the client
> anything.  The window of opportunity could be lessened by putting a signal
> (SIGUSR1, SIG_IGN); into the read_request_line code. 

Isn't that a bit risky? Can't it ignore USR1 as soon as we've read the
request line (inside read_request()?). Or will clients treat it as a
timeout at the server end, and always re-try? 

> I've been running this one on a 10 hit/second server with hourly USR1s for
> 12 hours with nothing bad to report yet.  Linux with LINUX_TWEAK. 

Without LINUX_TWEAK it fails because it cannot find the scoreboard file
after a USR1. (This is because detach() chdir's to /, but reinit_scoreboard
uses "logs/scoreboardfile" as the filename to open).

//pcs