Neoview Workload Management Services Guide (R2.4)

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 executing 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 = EXEC?
No
No
Yes
Yes
Yes
No
WMS sets the
warning level
and saves
warning
information.
Has the condition of a
compilation rule
been met?
Yes
No
No
Is the average
memory usage <=
MAX_MEM_USAGE?
Is the average CPU
busy <=
MAX_CPU_BUSY?
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 returns an SQL
command to the
NDCS server. This
command executes
before the main
query.
WMS allows the
query to start
executing.*
*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.
If there are no compilation rules in effect for the service or if none of the conditions of the
compilation rules is met, WMS checks if there are sufficient resources to execute the query.
When there are sufficient system resources, a query can enter into execution directly or from
How WMS Applies Rules and Services 21