Kbase 17492: What prostrct add Does With the Variable length Extent
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
10/05/1998 |
|
What prostrct add Does With the Variable length Extent
When choosing to add additional extents to a multivolume database,
you can use the probkup,prorestore into a new multivolume structure
file,or you can use the prostrct add utility.Although the prostrct
add utility is very well documented, it fails to mention exactly
what happens to the existing extents.
There are several different conditions under which you can decide to
add additional extents.Here are a couple.
1)If your current database has a fixed extent(s) that have not yet
been written to,you would then run prostrct remove on the variable
lenght extent (assuming you have one defined),run prostrct add for the
new extents,then on restart you will continue writing to the
predefined fixed length extents,then move on to the new ones.
2)If you are currently writing to the variable length extent,the
extent will then become fixed at the point at which the session ends
before the prostrct add.This extent must be at least 32k in length or
else you will recieve an error that the add operation failed.At this
point we will mark this extent fixed and round it of to a multiple of
32 in size,and it will be a fixed extent from this point on regardless
of size.
NOTE:THIS IS NOT RECOMMENDED FOR VARIABLE LENGTH EXTENTS NEAR THE 2GIG
LIMIT AS THE ROUNDING OFF TO A MULTIPLE OF 32 MAY HIT THE 2GIG LIMIT.
YOU CAN ONLY REMOVE EMPTY EXTENTS,AND ADDED EXTENTS MUST BE EMPTY.
Run the prostrct add with just the new extents.This will update the
database structure file.The next time you run prostrct list you will
see the new extents in the structure file.
This entire process is very well documented in the System
Administration II Guide for version 6 pp.6-26 to 6-30 and the System
Administration Guide for version 7 pp 7-34 to 7-40.
12/18/97 SDA
Progress Software Technical Support Note # 17492