Re: push data from server to client web browser

Note that I don't think a persistent connection is possible if you have the
potential to have a lot of users (which means it might work fine for
intranet). I say this because I ran across an issue while using JMeter with
a customer of mine that was submitting thousands of XML requests to Apache,
and RPG-XML Suite (www.rpg-xml.com) was processing the request and spitting
back out a response (very much akin to AJAX request/response cycle). The
issue was that the Apache server would all of the sudden start
dropping/rejecting requests and of course IBM put the onus on me to prove
that my product wasn't the issue (third time I have had to do that dance
with IBM). It turns out that Apache has a configurable finite amount of
queueing it can do for requests coming in on a port (which is a process
completely separate and before the request hits an OS400 job). As I
understand it, and as IBM finally explained to us after 6+hrs on the phone,
once this thread queue is full then Apache will just start
dropping/rejecting requests unknown to anybody admining the server and only
known to the person getting rejected (JMeter in this case). This is
contrary to my original thought process of thinking that even if a small
AS400 was getting nailed it could queue up thousands upon thousands of
requests and have them appropriately processed by 100 or so prestarted
Apache instance OS400 jobs. I guess I was wishing big. Can anybody else
"hone" my statements or confirm them? I do realize I am a little vague as I
forgot where the finite configurable Apache value was specified (thought is
was somewhere in CFGTCP and not necessarily related to Apache, but instead
inherrently because Apache uses sockets).

HTH,
Aaron Bartell
http://mowyourlawn.com



On Thu, Sep 25, 2008 at 3:52 PM, <elehti@xxxxxxxxxxxxxxxxxx> wrote:

But what about keeping the HTTP connection between the client and the
server open indefinitely in RPG IV CGI programming?

The Oreilly book http://oreilly.com/openbook/cgi/ch06_06.html
in chapter 6 says about CGI programming,
It provides the programming code for two examples of server push and
contrasts that to client pull.
The HTTP connection between the client and the server is kept open
indefinitely.
Server push involves sending packets of data to the client periodically,
as shown in Figure 6.8.

Server Push
Server push animations can be created using the

multipart/x-mixed-replace MIME type. The "replace" > indicates that each
data packet replaces the previous data packet. As a result, you can make
smooth > animations. Here is the format in which this MIME type is used:


I thank ALL of you very much for the comments you have shared so far.
EricL