topic Re: Extending AIJ files in Operating System - OpenVMS

Extending AIJ files

Jim Lahman_1 — Wed, 07 Mar 2007 12:05:42 GMT

Last year, I created an Rdb database with 14 after-image journal (AIJ) files whose sizes are 500 blocks apiece. Now, I need to make these AIJ files larger?

Can I just extend the existing AIJ files are do I need to recreate new AIJ files?

Attached is the command I used to create the AIJ files.

Thanks, Jim

Re: Extending AIJ files

Hoff — Wed, 07 Mar 2007 12:22:45 GMT

The versions of Rdb I've seen can use multiple static-sized files, or can use an extensible AIJ file. I've tended to use the extensible AIJ file, and to add and drop and cycle through additional AIJ files as and when needed.

While you're at it, I'd look at what disk activity was present, and quite possibly at spreading the database files (RDA and RDB, SNP, AIJ, etc) around, and onto different disk spindles, too. Where this can be reasonably managed.

It would not surprise me that you could perform this change-over entirely on-line and entirely safely, but I've tended to be paranoid when working with the local databases and have quiesced and performed an RMU BACKUP of before hacking around inside RMU or SQL. And only then after practicing on another testing database. Paranoid? Me?

Check the Rdb manuals for details.

Stephen Hoffman
HoffmanLabs

Re: Extending AIJ files

Karl Rohwedder — Wed, 07 Mar 2007 12:33:53 GMT

If the AIJ files are static (and switched in a round robin fashion by RDB), they cannot be enlarged on the fly. You may add addtional AIJ files online, if there a free slots in the database (check with RMU/DUMP/HEADER).

To make the space inside the AIJ files available again, you should perform an AIJ backup (using RMU), This AIJ backup can be made automatic, so the whole AIJ handling becomes transparent). For help see HELP RMU.

The RMU/SHO STAT has some nice AIJ displays also.

regards Kalle

Re: Extending AIJ files

Jim Lahman_1 — Wed, 07 Mar 2007 12:40:34 GMT

Yes, I have the .SNP files on its own RAID, the RDB and RDA files on another RAID and the AIJ, AIJBCK files on a third raid.

I have four available AIJ slots.

Jim

Re: Extending AIJ files

Jan van den Ende — Thu, 22 Mar 2007 16:12:26 GMT

Jim,

on issues like this, I tend to look at the Oracle site first.
Although Rdb ( & DBMS) info can be relatively hidden (sounds familiar, considering VMS at HP site, eh?)

hth

Proost.

Have one on me.

jpe

Re: Extending AIJ files

Jeff Bath — Sat, 07 Apr 2007 22:48:15 GMT

Jim,

Since you have 4 available slots you can add 4 more journals of whatever size you like. For the existing journals if they are backed up and are not the current journal you can drop them and add new ones of the appropriate sizes. To switch from the current active journal (so you can back it up and drop it to create a larger one) you would issue rmu/set after_journal/switch db-name.

You can use rmu and/or sql to add and drop aijs.

Jeff