Kbase 20999: How Many Databases Can a Client Connect at the Same Time?
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
10/16/2008 |
|
Status: Unverified
GOAL:
How many databases can a single client connect to at the same time?
FIX:
Client startup parameter -h specifies how many entries the client has for its internal connection table. The default value is 5, however it can be set as high as 240.
There are several other constraints which may prevent the client from actually connecting to that many databases.
1) In client-server mode, connections should be successful as long as there are 240 sockets open, and enough open files are allowed (sockets use file descriptors so they count as open files too).
2) In single-user mode sockets are not needed, but the ability to open all the files for each database is. The buffer pool and other data structures need to fit into the process address space. Connection to a large amount of databases should not be a problem if large values for -B are not used, and there are not too many files for each database, .
3) For self-serving clients in multi-user mode, all the files for the databases need to be open and also be able to attach all the shared memory segments for all the databases.
In the end, a reasonable practical limit is about 10 databases connected at once. Even then, if each of these 10 databases has 250 extents, connection may fail.