[Seaside] Re: Database Integration

[David T. Lewis]

On Sun, Jun 04, 2006 at 12:03:33PM +0200, Adrian Lienhard wrote:
> We experienced big concurrency problems (data corruption, lockups)  
> with OmniBase on Linux, accessing the same DB from multiple Squeak  
> images. Unless you are on Windows I would not recommend OmniBase.  
> Furthermore, OmniBase is much less transparent than for example GOODS  
> or Magma and can be tricky to use with Seaside.

For the record, I suspect that I may be partly to blame for this.
The Unix file locking in OSProcess has a setting that attempts to
emulate Windows file locking semantics, and I unfortunately distributed
OSProcess with this as the default preference. This emulation 
cannot be done correctly for separate Squeak images, which makes
it pretty much useless for any practical application.

So if there were data integrity problems with an OmniBase
application that used file locking with Win32 emulation enabled,
it may not be caused by OmniBase. If anyone tries this again
(and I hope that someone will do so), please make sure that the
Win32 emulating is turned off:
  OSProcessAccessor emulateWin32FileLocking: false

I can't say anything about the other concurrency issues, but I don't
want OmniBase to take the rap for a mistake that I made.

Thanks,
Dave