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From:Guilhem Bichot Date:July 27 2007 12:58pm
Subject:Re: I don't understand how SHOW SLAVE HOSTS works
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On Tue, Jul 17, 2007 at 09:50:51AM -0400, Baron Schwartz wrote:
> I have been trying to understand the behavior of SHOW SLAVE HOSTS, and it 
> didn't seem to match the documentation, so I went to the source and got 
> confused more :-)
> I'm sure I am commiting several sins here including looking at 5.1 code 
> while running 5.0.40, but the code I'm looking at is the Doxygen-ized 5.1 
> code of sql/ at 
> So far, I find there is a hash table called slave_list, which is inserted 
> from register_slave() and read from the function (whose name I have now 
> forgotten and can't see) called by SHOW SLAVE HOSTS.
> It looks to me like the command doesn't work quite like it is supposed to.  

It is unfinished code (part of a "failsafe replication" project which
was never finished). Slaves don't disappear from the list when they
disconnect... There is also
and to fix this one, we are going to change the semantics of SHOW
SLAVE HOSTS, but that won't be better. I think there is a plan to
deeply rework SHOW SLAVE HOSTS but that is long-term.
So for now, my honest advice would be to not lose your time on
studying this command :-/

   __  ___     ___ ____  __
  /  |/  /_ __/ __/ __ \/ /    Mr. Guilhem Bichot <guilhem@stripped>
 / /|_/ / // /\ \/ /_/ / /__   MySQL AB, Lead Software Engineer
/_/  /_/\_, /___/\___\_\___/   Bordeaux, France
I don't understand how SHOW SLAVE HOSTS worksBaron Schwartz17 Jul
  • Re: I don't understand how SHOW SLAVE HOSTS worksGuilhem Bichot27 Jul