Re: Q: Why is 7.3.2.2 forcing 4 character SID limit???

Torfrid Leek wrote:
>
> In article <32AFC72C.49DA_at_qrcsun.qrc.org>, "Lun Wing San (Oracle)" <wslun_at_qrcsun.qrc.org> writes:
> > Gary Assa wrote:
> > > ORA-07320: smsget: shmat error when trying to attach sga.
> > > SVR4 Error: 22: Invalid argument
> > > ORA-07306: sms1sg: shmget error, unable to get a shared memory segment.
> > > SVR4 Error: 17: File exists
> > > Additional information: 1
> > >
> > > when trying to create a 7.3.2.2 database. Well, it turns out that if I
> > > change my ORACLE_SID to 'tst2' instead of 'test02', I do not get the
> > > error. I know Oracle suggests a 4 character limit on the SID, but we have
> > > 5 or so databases, and there is no way would would change our SIDs to
> > > a 4 character limit.
> > >
> > > Does anyone else have this problem, or could it possibly be that I am
> > > running out of memory, and cutting off those 3 characters actually
> > > makes a difference????
> >
> > You can use longer than four characters in system identifier. Anyway, your error seems
> > to indicate that some files are shared with other databases. As a result, when you
> > rename the system identifier, all errors went. Please check the parameter file about the
> > location of the control file, redo log files and rollback segments.
>
> It is certainly possible to have 7.3.2.2 databases with a SID longer than 4
> characters.
>
> We had this problem once, and we also thought the name was the problem - we
> wanted to call it TEST.
> But it turned out that there were things hanging around from a previous db
> creation attempt. From the error messages you are getting it looks like it
> could be the sgadef file. We deleted that and semaphores, and a reboot fixed
> the problem.
>
> Regards, Torfrid
>
> torfrid.leek_at_usit.uio.no

It looks like the sid that you picked hashes to the same value as some other sid. I know it is hard to believe that you could possibly choose two names that hash to the same value but it is not all that uncommon. You can have sid names greater than 4 characters.

It uses this hased value to map shared memory so when it tries to grab the sga it thinks that something is already using the memory (really another instance is).

Hope this answers your question. Received on Tue Dec 17 1996 - 00:00:00 CST