(PECL mysqlnd_qc >= 1.0.0)
mysqlnd_qc_get_core_stats — Statistics collected by the core of the query cache
Returns an array of statistics collected by the core of the cache plugin. The same data fields will be reported for any storage handler because the data is collected by the core.
The
PHP
configuration setting
mysqlnd_qc.collect_statistics
controls the collection of statistics. The collection of statistics
is disabled by default for performance reasons.
Disabling the collection of statistics will also disable the collection
of time related statistics.
The
PHP
configuration setting
mysqlnd_qc.collect_time_statistics
controls the
collection of time related statistics.
The scope of the core statistics is the
PHP
process.
Depending on your deployment model a
PHP
process may handle one or multiple requests.
Statistics are aggregated for all cache entries and all storage handler.
It is not possible
to tell how much queries originating from
mysqli
,
PDO_MySQL
or
mysql
API calls have
contributed to the aggregated data values.
Această funcție nu are parametri.
Array of core statistics
Statistic | Description | Version |
---|---|---|
cache_hit
|
Statement is considered cacheable and cached data has been reused. Statement is considered cacheable and a cache miss happened but the statement got cached by someone else while we process it and thus we can fetch the result from the refreshed cache. | Since 1.0.0. |
cache_miss
|
Statement is considered cacheable...
|
Since 1.0.0. |
cache_put
|
Statement is considered cacheable and has been added to the cache.
Take care when calculating derived statistics. Storage handler
with a storage life time beyond process scope may report
cache_put = 0 together with
cache_hit > 0 , if another process has filled
the cache. You may want to use
num_entries from
mysqlnd_qc_get_cache_info() if the handler
supports it (
default ,
APC ).
|
Since 1.0.0. |
query_should_cache
|
Statement is considered cacheable based on query string analysis.
The statement may or may not be added to the cache. See also
cache_put .
|
Since 1.0.0. |
query_should_not_cache
|
Statement is considered not cacheable based on query string analysis. | Since 1.0.0. |
query_not_cached
|
Statement is considered not cacheable or it is considered cachable but the storage handler has not returned a hash key for it. | Since 1.0.0. |
query_could_cache
|
Statement is considered cacheable...
|
Since 1.0.0. |
query_found_in_cache
|
Statement is considered cacheable and we have found it in the cache but we have not replayed the cached data yet and we have not send the result set to the client yet. This is not considered a cache hit because the client might not fetch the result or the cached data may be faulty. | Since 1.0.0. |
query_uncached_other
|
Statement is considered cacheable and it may or may not be in the cache already but either replaying cached data has failed, no result set is available or some other error has happened. | |
query_uncached_no_table
|
Statement has not been cached because the result set has at least
one column which has no table name in its meta data. An example of
such a query is
SELECT SLEEP(1) . To cache those
statements you have to change default value of the PHP configuration directive
mysqlnd_qc.cache_no_table and set
mysqlnd_qc.cache_no_table = 1 . Often, it is not
desired to cache such statements.
|
Since 1.0.0. |
query_uncached_use_result
|
Statement would have been cached if a buffered result set
had been used. The situation is also considered as a cache miss and
cache_miss will be incremented as well.
|
Since 1.0.0. |
query_aggr_run_time_cache_hit
|
Aggregated run time (ms) of all cached queries.
Cached queries are those which have incremented
cache_hit .
|
Since 1.0.0. |
query_aggr_run_time_cache_put
|
Aggregated run time (ms) of all uncached queries that
have been put into the cache. See also
cache_put .
|
Since 1.0.0. |
query_aggr_run_time_total
|
Aggregated run time (ms) of all uncached and cached queries that have been inspected and executed by the query cache. | Since 1.0.0. |
query_aggr_store_time_cache_hit
|
Aggregated store time (ms) of all cached queries.
Cached queries are those which have incremented
cache_hit .
|
Since 1.0.0. |
query_aggr_store_time_cache_put
|
Aggregated store time (
ms ) of all uncached queries that
have been put into the cache. See also
cache_put .
|
Since 1.0.0. |
query_aggr_store_time_total
|
Aggregated store time (ms) of all uncached and cached queries that have been inspected and executed by the query cache. | Since 1.0.0. |
receive_bytes_recorded
|
Recorded incoming network traffic (
bytes ) send from MySQL to PHP.
The traffic may or may not have been added to the cache. The
traffic is the total for all queries regardless if cached or not.
|
Since 1.0.0. |
receive_bytes_replayed
|
Network traffic replayed during cache. This is the total amount of incoming traffic saved because of the usage of the query cache plugin. | Since 1.0.0. |
send_bytes_recorded
|
Recorded outgoing network traffic (
bytes ) send from MySQL to PHP.
The traffic may or may not have been added to the cache. The
traffic is the total for all queries regardless if cached or not.
|
Since 1.0.0. |
send_bytes_replayed
|
Network traffic replayed during cache. This is the total amount of outgoing traffic saved because of the usage of the query cache plugin. | Since 1.0.0. |
slam_stale_refresh
|
Number of cache misses which triggered serving stale data until the client causing the cache miss has refreshed the cache entry. | Since 1.0.0. |
slam_stale_hit
|
Number of cache hits while a stale cache entry gets refreshed. | Since 1.0.0. |
Example #1 mysqlnd_qc_get_core_stats() example
<?php
/* Enable collection of statistics - default: disabled */
ini_set("mysqlnd_qc.collect_statistics", 1);
/* Enable collection of all timing related statistics -
default: enabled but overruled by mysqlnd_qc.collect_statistics = 0 */
ini_set("mysqlnd_qc.collect_time_statistics", 1);
/* Populate the cache, e.g. using mysqli */
$mysqli = new mysqli('host', 'user', 'password', 'schema');
/* Cache miss and cache put */
$mysqli->query("/*qc=on*/SELECT id FROM test");
/* Cache hit */
$mysqli->query("/*qc=on*/SELECT id FROM test");
/* Display core statistics */
var_dump(mysqlnd_qc_get_core_stats());
?>
Exemplele de mai sus vor afișa:
array(26) { ["cache_hit"]=> string(1) "1" ["cache_miss"]=> string(1) "1" ["cache_put"]=> string(1) "1" ["query_should_cache"]=> string(1) "2" ["query_should_not_cache"]=> string(1) "0" ["query_not_cached"]=> string(1) "0" ["query_could_cache"]=> string(1) "2" ["query_found_in_cache"]=> string(1) "1" ["query_uncached_other"]=> string(1) "0" ["query_uncached_no_table"]=> string(1) "0" ["query_uncached_no_result"]=> string(1) "0" ["query_uncached_use_result"]=> string(1) "0" ["query_aggr_run_time_cache_hit"]=> string(1) "4" ["query_aggr_run_time_cache_put"]=> string(3) "395" ["query_aggr_run_time_total"]=> string(3) "399" ["query_aggr_store_time_cache_hit"]=> string(1) "2" ["query_aggr_store_time_cache_put"]=> string(1) "8" ["query_aggr_store_time_total"]=> string(2) "10" ["receive_bytes_recorded"]=> string(2) "65" ["receive_bytes_replayed"]=> string(2) "65" ["send_bytes_recorded"]=> string(2) "29" ["send_bytes_replayed"]=> string(2) "29" ["slam_stale_refresh"]=> string(1) "0" ["slam_stale_hit"]=> string(1) "0" ["request_counter"]=> int(1) ["process_hash"]=> int(3547549858) }