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Conference azur::mcc

Title:DECmcc user notes file. Does not replace IPMT.
Notice:Use IPMT for problems. Newsletter location in note 6187
Moderator:TAEC::BEROUD
Created:Mon Aug 21 1989
Last Modified:Wed Jun 04 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:6497
Total number of notes:27359

5981.0. "Repository Ids of private MIR" by FRAIS::WELLERSHAUS (Heidi Wellershaus) Fri May 06 1994 09:49

As mentioned in note 5728 and 5594 of this conference we are
using the mcc_mir routines within our TBL-project very extensively
to store our instance- and attribute-data in the private MIR.

Creation of attribute- and instance-repositories is done with
the routine mcc_mir_create_repository of DECmcc V1.3.0 (ULTRIX)
with the appropriate repository types MCC_K_DB_FTYPE_ENTDEF
MCC_K_DB_FTYPE_ATTRIBUTE by our own FM and AM.

Doing this in parallel within two processes the following
problems occur:

Problem 1:
        start process 1         start process 2
        create inst-repos 1
        ==> repos_id = 10
        create inst-repos 2
        ==> repos_id = 11
                                create inst-repos 3
                                ==> repos_id = 12
        create inst-repos 4
        ==> repos_id = 12 (!!)
        create inst-repos 5
        ==> repos_id = 13
                                create inst-repos 6
                                ==> repos_id = 13 (!!)

We assume, that process 2 gets the right repos_id the first time
creating one repository, but after that numbering of the repos_id
is done seperately by each process, that means the same repos-ids are reused.
This causes confusing and unacceptable behaviour and inconsistence
of the stored data.

Problem 2:
        create inst-repos 1
        ==> repos_id = 22
                                create inst-repos 2
                                ==> repos_id = 23
        create attr-repos 4
        ==> repos_id = 23 (!!)    

Reading and writing of these repositories
causes the following return status:
MCC_S_WRONGREPOSTYPE 52876290

Is this bug known by anybody, is there a bug-fix?

Heidi
T.RTitleUserPersonal
Name
DateLines
5981.1Sounds like a bug.TAEC::LAVILLATMon May 09 1994 11:1515
 Heidi,

  Your are not supposed to create MIR repositories very often, that is why
  *maybe* the access to the repository table is not well protected.

  I would suggest you enter a CLD for this problem, so that the MCC maintenance
  team is aware of it.

  I would also suggest that you work around the problem by doing the mutual
  exclusion yourself via flock or any other way.

  Regards.

  Pierre.