Neoview Workload Management Services Guide (R2.5)

Figure 1-4 How WMS Handles an Incoming Query
vst105.vsd
Incoming
query to
WMS
Is WMS in the
ACTIVE state?
No
Yes
Are the number of
queries on this
segment < max
allowed*?
Yes
Yes
Are there compilation
rules associated with
the service?**
Is the service ACTIVE?
Yes
No
No
Yes
Is the compilation
rule action =
REJECT?
Is the compilation rule
action = HOLD?
Is the compilation rule
action =
SQL_CMD?
No
No
Yes
Yes
Yes
No
WMS sets and
saves the
warning level.
Has the condition of a
compilation rule
been met?
Yes
No
No
Is the average CPU
busy <=
MAX_CPU_BUSY?
Is the average
memory usage <=
MAX_MEM_USAGE?
Yes
Yes
WMS places the
query in the
WAITING state.***
NoNo
WMS rejects the
request to execute
the query and returns
an error message to
the client application.
WMS places the
query in the
HOLDING state.***
WMS sends SQL
commands to the
NDCS server. Those
commands execute
before the main
query.
WMS allows the
query to start
executing.***
*The maximum number of executing and waiting queries per segment is preconfigured during the installation of WMS and is
typically 1000.
**If query statistics aggregation is enabled for the service, WMS ignores the compilation rules and proceeds with checking
the maximum CPU busy.
***If the query remains in this state longer than the timeout value, WMS cancels or rejects the query and returns an error
message to the client application.
How WMS Applies Rules and Services 25