Kbase P90775: When -cache is useful
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
10/16/2008 |
|
Status: Unverified
GOAL:
When -cache is useful
GOAL:
Compare connection times with or without -cache
FIX:
Tests with an Oracle schema holder containing 980 Tables, 4665 indexes, 1540 columns resulted in the following report.
The results would be equivalent for a Progress database or any other Foreign database schema holder.
REPORT:
The results show benefit of -cache when using DB over WAN (1,390 Milliseconds maximum compared to 53,893 minimum).
We have connection with TCP-IP loopback and -cache taking longer than connection with TCP-IP loopback and no cache ( 420 Milliseconds minimum compared to 250 maximum). As the figures above showed, we do not access just the cache file but we always access the schema holder also.
We have first connection to local schema holder in Read Only mode, -RO, taking longer than connection time with TCP-IP loopback and no cache (2,410 Milliseconds compared to 250 maximum) but following connections faster ( 100 Milliseconds compared to 250). When the schema is in memory, within the Buffer Pool, then accessing the database blocks is faster than accessing from a local file with potential extra I/O if no copy is left in the OS cache file. Depending on how the application is used by a Win32 user, a broker should be started on the schema holder. If the OS allows it, connection to the schema as self service client instead of using TCP-IP loopback would give better performance.