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发表于 2014-2-5 17:07:30 | 查看: 2355| 回复: 0
about PARALLEL_MAX_SERVERS

       
http://docs.oracle.com/cd/B28359_01/server.111/b28320/initparams188.htm#REFRN10175
PROCESSES
PROCESSES specifies the maximum number of operating system user processes that can simultaneously connect to Oracle. Its value should allow for all background processes such as locks, job queue processes, and parallel execution processes.

The default values of the SESSIONS and TRANSACTIONS parameters are derived from this parameter. Therefore, if you change the value of PROCESSES, you should evaluate whether to adjust the values of those derived parameters.


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http://docs.oracle.com/cd/E11882_01/server.112/e25523/parallel005.htm#autoId2
Oracle® Database VLDB and Partitioning Guide
11g Release 2 (11.2)
Part Number E25523-01
Tuning General Parameters for Parallel Execution



PARALLEL_MAX_SERVERS
==========================
The default value is:

PARALLEL_THREADS_PER_CPU x CPU_COUNT x concurrent_parallel_users x 5

In the formula, the value assigned to concurrent_parallel_users running at the default degree of parallelism on an instance is dependent on the memory management setting.
If automatic memory management is disabled (manual mode), then the value of concurrent_parallel_users is 1.
If PGA automatic memory management is enabled, then the value of concurrent_parallel_users is 2.
If global memory management or SGA memory target is used in addition to PGA automatic memory management, then the value of concurrent_parallel_users is 4.

The preceding formula might not be sufficient for parallel queries on tables with higher degree of parallelism (DOP) attributes. For users who expect to run queries of higher DOP, set the value to the following:

2 x DOP x NUMBER_OF_CONCURRENT_USERS

For example, setting the value to 64 enables you to run four parallel queries simultaneously, if each query is using two slave sets with a DOP of 8 for each set.

       
The error is from setting PARALLEL_MAX_SERVERS high i.e > 3600
CPU_COUNT is set default in database. Based on cpu_count, parallel_max_servers are set.
I would suggest to set parallel_max_servers to less value as mentioned in the Oracle document
       
         
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