It happened again. I was presenting best practices for upgrading to version 8 to clients and business partners on Monday and then I talked about ODS. Suddenly, I noticed that everyones eyes glazed over, as they weren't really sure what this TLA (Three Letter Acronym) was all about. As I suspect that more than just these esteemed people might not know for sure what ODS is and what it all has to do with Notes and Domino, let me take a moment to expand upon this as part of this blog entry.
On-Disk Structure (ODS)
Every major release of Notes/Domino (e.g., versions 2, 3, 4, 5, 6/7 and now 8) has included significant architectural changes to the database structure, also known as the On-Disk Structure (ODS). These architectural changes enables the Notes and Domino development team to improve performance and scalability in each release. Upgrading the databases provides a lot of benefits, with very low risk, so this has always been an important early step in any Notes and Domino upgrade plan.
The ODS version for each major release of Notes and Domino is as follows:
- v2 -- ODS 16/16.3
- v3 -- ODS 17/17.3
- v4 -- ODS 20
- v5 -- ODS 41
- v6/v7 -- ODS 43
- v8 -- ODS 48
So there is now a new ODS for Notes and Domino 8, which is ODS 48. However, that ODS version is not enabled by default for new or upgraded applications. This permits an easy migration from 6.5 and 7.0 environments.
So what does ODS 48 provide?
A major consideration for mail servers when considering upgrading to a newer version of Domino is the impact this will have on disk space utilization resulting in the use of the new mail template. Typically, new templates imply new features and new functionality and these generally require more space by the newer design contained in the template. With version 8, it is no exception. There is considerably more features offered to the user and these will consume more space. The Notes Mail 7 Template requires 17 GB of disk space (for the design alone) whereas the Notes Mail 8 Template requires 25 MB (both based on ODS 43).
Thus, if the design is applied to 1,000 mail files present on the server, there will be an increase of 8GB in disk space utilization, for a total of 25GB just for the design alone. Given that many servers handle more than 1,000 users (and a commensurate number of mail files), this may have a broader impact on disk space utilization.
So ODS 48 helps by enabling design note compression. This is an option by which the design notes within a database can be compressed as part of the new On Disk Structure in Notes and Domino 8. This feature reduces the size of databases by compressing design elements by up to 60%. For example, the design elements in a database based on the standard Notes 8 Mail template (Mail8.ntf) reduce in size from approximately 25MB to 11MB once design compression is implemented. The compression percentage achieved will vary from database to database based upon the individual compression ratio achieved for each design element in each database.
In real terms, it means that, upgrading to Domino 8 and ODS 48, there would be a decrease in disk space used just by upgrading instead of the customary increaase.The decrease, for 1,000 mail files would actually be of 6 GB, significantly decreasing the disk overhead on a per-mail file basis.
How is ODS 48 implemented?
As mentioned, ODS 48 is not enabled by default for new or upgraded applications. ODS 43 is the norm. To implement ODS 48, the parameter CREATE_R8_DATABASES=1 needs to be added to the notes.ini file to enable ODS 48 (Version 8) as the default.
Thus, for the Domino 8 server, applications residing on the server are upgraded in the following manner:
- The CREATE_R8_DATABASES=1 notes.ini parameter needs to be added to the notes.ini file on the Domino server (note: the parameter is dynamic and can be enabled with 1 or disabled with 0 using "set config"; as well, the parameter is not case sensitive);
- Load Compact -c against the applications that need to be upgraded to ODS 48 (note: if an application is updated by error, it is possible to revert the ODS to the previous release with Compact -r).
Any new applications created on the Domino server will be created with ODS 48, provided that the CREATE_R8_DATABASES parameter is set to 1. If the value is returned to 0 (zero), new applications will be created with ODS 43. The procedure is the same for the Notes client.
Frederic Dahm | 18 January 2008 12:46:25 AM ET | Montreal, QC | Comments (1)
