The Service Platform components are deployed on a WebSphere® Application Server Network Deployment platform to provide common service implementation functions. Use this information, along with your normal service support, to assist in tuning or troubleshooting Service Platform components.
You can also refer to the WebSphere Application Server information center for additional information specific to that product.
This component keeps track of service usage information and can constrain the rate of requests accepted by the service, both at the server level and cluster level. When used in a cluster, each cluster member maintains a local hierarchy of rate limiting buckets that are used to calculate request admission. Reservations for additional rate capacity are made against each operation as more rate is needed. When additional rate has been reserved, the allocate rate is added to the operation rate limiting bucket and the parent service rate limiting bucket. Limits set at the server level constrain the rate of requests for all operations executed against that service. Limits set at the operation level limit the rate of requests for the particular operation. The rate limit for the service bucket is the sum of the rates of its child operation buckets.
Exceed Operation limit recorded as ServiceAdmissionControlFault
Cluster service remaining | Cluster operation remaining | Local service limit (max 15) | Local operation limit (max 5) |
---|---|---|---|
15 | 5 | 0 | 0 |
Cluster service remaining | Cluster operation remaining | Local service limit (max 15) | Local operation limit (max 5) |
---|---|---|---|
10 | 0 | 5 | 5 |
Verification of whether a request can be admitted is performed using the local view. A reservation request may be denied at any time due to lack of sufficient rate at the service or operation level. When a node member receives a rejected reservation request, it will enter a silence period. This silence period will suppress additional reservation requests, reducing inter-cluster traffic and allowing the network to settle before attempting additional reservation. In steady state, this will minimize the inter-cluster messaging required.
If address masking does not work as expected, verify that you configured the masking and shadowing operations correctly. For example, are the right number of digits specified for shadowing? If masking expiry is used, has the specified time interval elapsed?