Kbase 16905: AIX 4.2.1 and performance problems
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
10/05/1998 |
|
AIX 4.2.1 and performance problems
If you have upgraded to AIX release 4.2.1 and are running Progress
versions older than 7.3E and 8.2A you should upgrade Progress. IBM
changed the behaviour of the write() system call when used with the
O_SYNC open() flag. This changes causes the Operating System to write
the data portion as well as the file access attribites when a block
is written to the file, prior to this change, only the data portion of
the file was written to.
What does this mean?
This means that every time Progress writes to the bi file we are
actually writing twice, once for data, and once for the header info.
Many vendors are moving towards this concept.
How does Progress 7.3E and 8.2A help?
Instead of using the O_SYNC open flag, we are now using the O_DSYNC
open flag. This causes the write() system call to behave like it
did on 4.2.0 and previous versions of the Operating System
Progress Software Technical Support Note # 16905