[comp.protocols.nfs] Lock daemon intercation

leo@unipalm.uucp (E.J. Leoni-Smith) (05/14/91)

I want to use the news to air a problem we have encountered: I am
not 100% sure of exactly where the problem lies, but I will relate the
whole history and await your comments....

We are bringing up an internal database system based on informix 4GL.
The target platform WAS to have been a SUN SPARC, but on loading
the Informix, and the 4GL programs, it was discovered that the SUN
informix port did not support kernel file and record locking - it
used an infamous arrangement of lock files.

On being pressured Informix said that the SUNOS port with kernel locking
was 'too slow to be useable'.


Since the 4GL code depended on the 'wait for lock' feature which
was not implemented - we had to rapidly switch to SCO-ODTY - which 
we had a latest release of courtesy SCO. 

This worked OK after upping every single tuneable kerenle parameter in sight
by a factor of about 10 :-) BUT when more than two users attempted to open
the database (consisting of some 115 files including indexes (indices?))
we would encounter delays of up to FIVE MINUTES.

judicious use of 'ps' showed that a process 'lockd' was consuming
MINUTES of CPU time. 

This was duly terminated with extreme prejudice - and fours users
screens sprang to life and we haven't looked back since.....

ALSO, ODT doesn't hang around for 30 secs on the VERY FIRST LOGON after
you type in 'root' or whatever, before issuing the 'password:' prompt.

Strange huh.

What I suspect - and it scares the ***** out of me, is that hanging an
NFD lockd onto a unix OS RUINS the performance of kernel locking to
such an extent that it becomes unuseable for database ap[plications.

We noticed that INGRES was also incredibly slow sometimes on ODT running NFS
and the fact that SUNOS comes with the lockd as standard, and that
Informix then couldn't get good performance on that OS using kernel style
locking (lockf()) makes me suspicious.

Has anyone out there got anything to support or contest this? We are OK
since I don't need locking on that particular server anyway - But I would
really like to know the answer.

Thanks in advance
(p.s I don't know how to cross post this to comps.databases - if there is a 
moderator out there - could you ?)
Thanx