| Measurement |
Description |
Measurement
Unit |
Interpretation |
| Queries_registered |
The
number of queries that are registered with the cache
|
Number |
|
| Queries_added |
The
number of queries added to the cache during the last measurement
period |
Number
|
|
| Cache_hits |
The
number of times the cache was accessed during the last measurement
period |
Number
|
|
| Queries_deleted |
The
number of queries that were deleted from the cache during the last
measurement period |
Number
|
A high value could indicate low memory allocation for the query cache.
Since reading from the cache is less expensive than reading directly
from the database, a higher memory allocation to the cache is advisable.
|
| Non_cached_queries |
The
number of queries that were not cached (not cachable due to their
QUERY_CACHE_TYPE) during the last measurement period |
Number
|
|
| Free_memory |
The
amount of free memory in the query cache |
MB
|
A low value of this measure could cause subsequent queries to be rejected by
the cache, owing to low memory availability. It would be good practice
to tune the cache memory to handle more load.
|
| Free_blocks |
The
number of free memory blocks in the query cache currently |
Number
|
|
| Total_blocks |
The
total number of blocks in the query cache currently |
Number
|
|
| Total_queries |
This
is the sum of cache inserts, cache_hits, and cache_not_cached queries during
the last measurement period. |
Number
|
|