Enqueue Server Max Requests and Enqueue Table Size

If you start noticing I/O or memory errors in the dev_enqio_* trace file, the enqueue server is being overloaded.

enque/server/max_requests and enque/server/max_query_requests determine the number of requests that can be processed parallely. These numbers should atleast be equal to the number of work processes or the number of Java threads (in all instance).

enque/table_size determines the size of the enqueue table. If there is a memory error in the trace files, increase enque/table_size.

Sample calculations of the max_*request parameters based on number of WPs/threads and enqueue table size:

For ASCS

Total number of WPs = 1000
Lock Table Size = 500MB

enque/server/max_query_requests = 1000
enque/server/max_requests = 1000 + 500 * 25 = 13500. #The additional 25*500 is for handling replication in HA systems.
enque/table_size = 500000

For SCS

Total number of Java Threads per node = 350
Total number of nodes = 3
Lock Table Size = 32MB

enque/server/max_query_requests = 3 * 4 * 350 = 4200
enque/server/max_requests = 4200 + 32 * 25 = 5000
enque/table_size = 32000

Comments

Popular posts from this blog

OS/DB Migration - CMD. STR, TOC, EXT, R3load, DDLDBS.TPL and more

Fixing Inconsistent Table - Table activation fails due to inconsistency between DD and DB

301 Redirect Using SAP Web Dispatcher