tomcat-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From GOMEZ Henri <>
Subject RE: [PROPOSAL AJP14] AJP13 Evolution
Date Tue, 08 May 2001 22:16:53 GMT
>ajp13 reuses connections, but, in general for each "worker" 
>there will be a
>pool of connections between the web server and the servlet 
>engine.  That way
>it can handle multiple requests concurrently, but still save 
>on the socket
>creation time (since connections are reused for many requests).

>So deciding which connection to send the admin messages on is, in fact,
>important.  Not only do we have to watch out for resending 
>data, but we also
>have to make sure we send data to all the participating web servers
>(multiple Apaches can talk to one TC, and, if they do so, they 
>can all hit
>the same port, in which case some ajp13 threads are talking to 
>one, some to

Each AJP14 thread in Tomcat must send admin messages. It will
be the task of web-server to remove duplicate messages.
>Maybe we should tag the TC->Apache admin messages with an id 
>-- that way we
>could just send them out on all conections, and the various 
>Apache children
>would make sure they only react to a given message once (possibly
>communicating w/ each other via shared memory).  This will 
>make the problem
>of informing all participating Apache instances go away, and 
>we may need to
>play some shared memory games in any event, to make sure that 
>all the Apache
>procs are brought up to date.

+1 for the ID of admin messages, which make the removing easier.
shared memory will make mod_jk port on differents web-server/OS
more harder, and we might introduce here the use of APR.

But there is APR specialists around !=)
>Mike Braden wrote:
>> Why not just handle each connection as if it is a connection
>> from a different server, logging in each time.
>> Are ajp13 requests serialized? ajp13 only connects to TC
>> once to the port set in the config, right?
>> -----Original Message-----
>> From: 
> Behalf Of jean-frederic clere
> Sent: Tuesday, May 08, 2001 5:19 AM
> To:
> Subject: Re: [PROPOSAL AJP14] AJP13 Evolution
> Apjp13 requests are not multiplexed, so we need more that one connection.
> How
> could we decide on which connection we send the admin message? Otherwise
> will
> the send the same data more than once.


Dan Milstein //

View raw message