Hello All TurboIMAGE users:

Those of you who were able to attend SIGIMAGE at HP
World will I am sure remember the slide that Tien-You Chen
put up on "TurboIMAGE Limits".  The HP R&D Database Lab
has been funded by the CSY Growth Solution Team to
investigate expansion of various MPE and IMAGE limits that
users have run in to, or may run in to in the near future.

The SIGIMAGE Executive Committee (SIEC) is working with
HP to come up with a detailed user survey on what limits users
need to have increased;  have they run in to the limit(s) already;
how severe a problem is it causing / will it cause;  how big
should the increase be in each case where there is a need; etc.

Note that this will *NOT* be a "traditional" SIGIMAGE Ballot,
where users get a certain number of votes / dollars to "spend".
The Limits Survey will tend to be more of an essay test..    :-)

Anyway, while survey prep is in process, I've been asked by
users to post the complete list of current limits to 3000-L, so
that people can do a preliminary review of the items & numbers
associated with each.....  That's a reasonable request, so
attached find said *PRELIMINARY* info;  i.e.: this is not, repeat:
*NOT* the survey.  That will be posted... um... soon... (soon as
I get it finished and reviewed).  Please wait for the survey before
formally sending feedback....  of course any and all desired
discussion on 3000-L is as usual a given.

I might add that if somehow a user out there thinks there is
a missing TurboIMAGE-related limit that should be added to
this list, please reply to 3000-L or to me directly ASAP.  My
take is that the Lab has been pretty thorough in listing current
limits, but it's always possible there might be an omission.

Anyway, pending post of formal survey here is the "current
limits" list.....

Ken Sletten
SIGIMAGE Chair
[log in to unmask]
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> SYSTEM:
>
>   2004 databases can be opened concurrently on a system
>
> DATABASE:
>
>   1023 data items can be defined in a database
>   199  data sets can be defined in a database
>   63   passwords can be defined in a database
>
> DATA SET:
>
>   255  data items can be defined in a data set
>   16   paths can be defined in a master data set
>   16   paths can be defined in a detail data set
>   1    data item can be locked at a given time in a data set
>   2**31 - 1  (2.15G)  entries maximum in a data set
>   2**31 - 1  (2.15G)  entries maximum in a chain
>
> DATA ITEM:
>
>   255  subitems can be defined in a data item
>
> PROCESS:
>
>   127 DBOPENs per process without calling DBCLOSE
>   63  DBOPENs per process to open the same database
>   127 DBOPENs per remote process without calling
        DBCLOSE
>   63  DBOPENs per remote process to open the same
        database

> LENGTH:
>
>   510  bytes for maximum subitem length
>   4096 bytes for maximum item length
>   4756 bytes for maximum entry length
>   5120 bytes for maximum block length
>   4096 bytes for maximum lock descriptors size when
          calling DBLOCK mode 5/6
>   252  bytes for maximum b-tree index key size
>
> TRANSACTION:
>
>   15   databases can be involved in a transaction (either
      DBBEGIN/DBEND or DBXBEGIN/DBXEND transaction)
>   4MB  opened transactions for a process
>   64MB opened transactions for a volume set
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