Re: Informix won't work with NFS?

In <1993Nov1.175754.11393@informix.com> davek@informix.com (Dave Kosenko) writes: >Charles Yamasaki writes: >|> Graeme Sargent writes: >|> >|> >Yes, I suspect that is pretty unusual, sine Informix doesn't support >|> >that scenario. >|> >|> Well, not so mmuch so. I'd love to be able to do something similar. If >|> I pay for a 16 user license why does it matter what machine they are on? >|> >|> >It seems to me that it is not unreasonable for a database vendor to >|> >require the database to be local to the database server processes, as >|> >there are significant performance implications for any other scenario >|> >which could impact their product's reputation. >|> >|> Well, that's not a good excuse. If someone complained about performance >|> Informix could just say "what's the environment?" and follow up with >|> "well no wonder". >[ and this goes on and on quite a bit ] >As far as I understand it, we disallow access of a database existing on an >NFS mounted filesystem because of problems associated with distributed lock >managers in Unix. Since SE uses Unix system calls to handle its locking, >we cannot guarantee that a lock placed on a row in the database by CPU1 will >be respected when that same row is accessed by CPU2. Without that locking >capability, the integrity of the db is jeapordized, so we simply disallow >access. I did not intend to present performance as the *only* reason for disallowing NFS (although I now realise I gave that impression). However, as I understood it, it was the primary reason given by Product Marketing for not supporting it (originally, I grant this may have changed in the last few years). NFS record locking I thought provided sufficient functionality for SE, however IMHO it does not work reliably (even on a Sun, let alone anything else) and performance (when it does work) is lousy. graeme -- Disclaimer: The author's opinions are his own, and not necessarily those of Pyramid Technology Ltd. or Pyramid Technology Inc. --------------------------------------------------------------------------- -m------- Graeme Sargent Voice: +44 (0)252 373035 ---mmm----- Senior Database Consultant Fax : +44 (0)252 373135 -----mmmmm--- Pyramid Technology Ltd. Telex: Tell who??? -------mmmmmmm- Farnborough, Hants GU14 7PL Email: graeme@pyra.co.uk --------------------------------------------------------------------------- We have the technology. The tricky bit is learning how to use it.