NUM_EVICTED

NUMBER

Number of evicted subshards across all sharded queues

NUM_PREFETCHED

NUMBER

Number of subshards pre-fetched by AQ background process

NUM_UNEVICTION

NUMBER

Number of subshards un-evicted by foreground process (like dequeue process)

NUM_UNCACHED

NUMBER

Number of subshards stored as uncached

NUM_TRACKED

NUMBER

Number of subshards which are actively tracking dequeue rates

NUM_CACHED

NUMBER

Number of subshards stored as cached

MAX_SUBSH_SIZE

NUMBER

Maximum subshard size seen till now, in terms of number of messages per subshard

MIN_SUBSH_SIZE

NUMBER

Minimum subshard size seen till now, in terms of number of messages per subshard

MEAN_SUBSH_SIZE

NUMBER

Mean subshard size seen till now, in terms of number of messages per subshard

AVG_EVICTION_RATE

NUMBER

Average number subshards evicted per second

AVG_LOAD_RATE

NUMBER

Average number of subshards pre-fetched or un-evicted per second

AVG_EVICTION_TIME

NUMBER

Average time taken to evict one subshard (in milliseconds)

AVG_LOAD_TIME

NUMBER

Average time taken to un-evict one subshard (in milliseconds)

AVG_MISS_RATIO

NUMBER

Average ratio of number of foreground un-evictions versus background pre-fetch

AVG_THRASH_RATIO

NUMBER

Average ratio of number of subshard pre-fetched by background without dequeue attempt versus total number of subshards prefetched

MANDATORY_AFF_SWITCH_ATTEMPTS

NUMBER

An affinity switch is a change in dequeue instance for a shard-subscriber pair. A mandatory affinity switch is when there are local enqueues in the queue at the instance but no local dequeues present, so the dequeue affinity is switched to another instance for that shard-subscriber pair. This column shows the number of times mandatory affinity switches were attempted across all instances. Populated at the smallest instance id only.

OPTIONAL_AFF_SWITCH_ATTEMPTS

NUMBER

Optional affinity switches are affinity switches that are not mandatory. Optional affinity switches are done for global load balancing across the Oracle Real Application Clusters (Oracle RAC) database. This column shows the number of times optional affinity switches were attempted across all instances. Populated at the smallest instance id only.

CON_ID

NUMBER

The ID of the container to which the data pertains. Possible values include:

• 0: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs.

• 1: This value is used for rows containing data that pertain to only the root

• n: Where n is the applicable container ID for the rows containing data