Hello Angus,
I don't think I explained properly. The FTP server and Database are completely unrelated except for the fact that they share the same exe. In an ideal world, they'd be two completely independent exe's but the spec of this program means that one exe has got to be both a database engine and an FTP server. However the FTP server isn't doing very much.... I have a client program myapp.exe which when it starts logs into the FTP server to see if there is an updated version of itself, if there is, then it downloads it, if there's not, then it logs off the ftp server and gets on with being a database client app. So all the FTP server is doing is supplying a directory listing to myprogram.exe and then with an updated exe if one exists. The FTP server and database NEVER talk to each other. -- regards David Tuesday, February 9, 2010, 2:44:00 PM, you wrote: >> ARMSL> Your server application also needs to take care with file >> lock timeouts, >> ARMSL> network timeouts, etc, to avoid blocking the main thread. >> >> Could you elaborate. I know very little about this subject. ARMSL> Provided you do not make database calls from any FTP server events, you ARMSL> will not have a problem. Generally, making simple database calls is ARMSL> painless since they usually respond within 20ms and that is the time ARMSL> during which the FTP server will stop responding to all clients. But you ARMSL> would not want to do a complex database query that took any longer ARMSL> without using a thread. ARMSL> But if the database needs to be re-opened and there is a network problem ARMSL> (since real databases are never on the same platform as an FTP server) ARMSL> there may be a 30 second timeout before the connection fails, and that ARMSL> means the FTP server also stops for 30 seconds. ARMSL> One of my applications used async database events, both opening and ARMSL> executing statements, with a queue for new statements that are needed ARMSL> before previous ones have completed, with a trigger emptying the queue, ARMSL> but it all gets very complicated, particularly the error handling. ARMSL> My FTP servers also log to a database, but this is very fast since it ARMSL> mostly does not need the response to be interpreted. ARMSL> The same issues apply to file event logging, opening a file on a network ARMSL> share may have a long timeout, during which the server is blocked. ARMSL> Angus ARMSL> -- ARMSL> To unsubscribe or change your settings for TWSocket mailing list ARMSL> please goto http://lists.elists.org/cgi-bin/mailman/listinfo/twsocket ARMSL> Visit our website at http://www.overbyte.be ############################################################ David Rose Navigator Systems Ltd, Network Business Centre, 3 Gloucester Street, Bath, BA1 2SE,UK Main Tel: +44 (0)207 183 0011 Fax: +44 (0)1225 464984 Company Email: da...@navigator.co.uk (Private e-mail on request) CONFIDENTIALITY NOTICE The contents of this e-mail are confidential to the ordinary user of the e-mail address to which it was addressed and may also be privileged. If you are not the addressee of this e-mail you may not copy, forward, disclose or otherwise use it or any part of it in any form whatsoever. If you have received this e-mail in error please e-mail the sender by replying to this message. -- To unsubscribe or change your settings for TWSocket mailing list please goto http://lists.elists.org/cgi-bin/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
