Problems with vServer Xtra 4MD

[Florian Bogeschdorfer]

Hi Ruslan!

It took me days to figure this out:

I use the vServer Xtra to find out if a database does already exists. If
not, I close the session again and all is fine. If it does though, I run a
sub to create all tables and fields.

After that I shutdown and restart the projector. I have always received a
weird script error which came up apparently after the "halt" command which I
use to end the running projector. I don't get any details with the script
error and since we speak about very few installations, I kind of accepted
the error, since it did not harm the installation and work progress.

Now I made an update of my application and in authoring all was fine (the
error is in the projector only). Unfortunately in runtime I got the error
again but this time not after the "halt" command but right after an alert
command in the middle of my scripts. Now in short without all details: after
really days of testing and a good hint on another list, I found out that it
had to be a callback from an xtra or similar and I started investigating
what I had changed and apparently I had enlarged the create table and fields
stuff a great deal.

So I investigated into the vServer Xtra and changed the timeout from 500 to
2000 and suddenly the error changed back to the halt command.

What I now think is:

If I use the vServer Xtra and do a lot of creating tables and fields with
the client Xtra, the vServer Xtra somehow runs into a timeout and calls back
Director, causing this error. Obviously the alert or halt command catches
this error then (enough time for the "callback") and produces an error
immediately after (we all know that "alert" stops the whole Director).

When I run the code for a second time, the DB must not be created again and
I don't get an error anymore. The only difference is the code creating
tables and fields. So in summary:

1. An callback is sent in combination with vServer Xtra and creating tables
and fields
2. The resulting error can be delayed with using higher timeouts. However it
can not be avoided
3. It is in runtime only
4. I tried closing the vServer connection with closeSession() and setting it
to 0 before calling the the create code but it did not help.

This is the last lines of the log:

10:47:28.558000 (188): (388) Flushing 'me-inside' database: OK
 10:47:28.558000 (188): (388) Closing database me-inside: OK
 10:47:28.558000 (1552): (388) Unknown error!
 10:47:28.558000 (1552): (388) ERROR #1019: Unknown server error 
 10:47:28.558000 (1552): Closing connection (388)

Best regards, Florian