Kbase 11437: How Does PROGRESS/STRUCTURE/CREATE Work?
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
5/10/1998 |
|
SUMMARY:
This entry details how PROGRESS/STRUCTURE/CREATE works to create a
database structure. This utility is usually used to create a new void
multi-volume structure that will be populated with PROGRESS/COPY
or procopy.
EXPLANATION:
Progress reads the structure description file, file.st, and
allocates disk space for the first extent (.d1). It puts a
header and footer in each block, and does it BLOCK by BLOCK.
On VMS Progress takes between 16 and 32 block groups and puts
headers and footers in each block.
This process can be very time consuming on VMS. CPU usage is
minimal, but IO usage is extremely high. It may be as high as
59%. Local Event Flag wait state is common. VMS checks that the process is not a runaway, and there is the accounting over-head that does this that adds to the time that is required to create a Progress database.
UNIX does not have the accounting overhead, and the process is
much faster.
Version 6.3 will have the number of blocks Progress can take at
one time to create a Progress database as a tunable parameter.
References to Written Documentation:
Progress System Administration