[TYPO3-dev] performace of cachingframework

[Bjoern Pedersen]

Am 18.02.2011 11:03, schrieb Peter Russ:
> 
> Sorry but your answer is not correct. Please check the code HOW it is
> handled in the dbbackend. Even if only true or false is returned query
> will always take lifetime into account.
> 
> Additionally there is an overhead as has and get are similar and always
> 2 queries are required to receive a cached item. So using dbbackend for
> caching might even increase the number of queries and slow down delivery
> on high load sites.
> 
> If you would consider this in your patch it would help more ;-)
> 
> Peter.
> 

Peter,

we are talking about two different things here. You are talking about
the handling in php. I am only talking about handling by the database.
And there is a key on identifier, so the number of records to check for
expiry is low.

mysql> explain select * from cachingframework_cache_pages where
identifier='xxxx' and crdate+lifetime>=now();
+----+-------------+------------------------------+------+---------------+----------+---------+-------+------+-------------+
| id | select_type | table                        | type | possible_keys
| key      | key_len | ref   | rows | Extra       |
+----+-------------+------------------------------+------+---------------+----------+---------+-------+------+-------------+
|  1 | SIMPLE      | cachingframework_cache_pages | ref  | cache_id
 | cache_id | 130     | const |    1 | Using where |
+----+-------------+------------------------------+------+---------------+----------+---------+-------+------+-------------+
1 row in set (0.03 sec)

mysql> explain select * from cachingframework_cache_pages where
crdate+lifetime>=now();
+----+-------------+------------------------------+------+---------------+------+---------+------+------+-------------+
| id | select_type | table                        | type | possible_keys
| key  | key_len | ref  | rows | Extra       |
+----+-------------+------------------------------+------+---------------+------+---------+------+------+-------------+
|  1 | SIMPLE      | cachingframework_cache_pages | ALL  | NULL
 | NULL | NULL    | NULL |    1 | Using where |
+----+-------------+------------------------------+------+---------------+------+---------+------+------+-------------+
1 row in set (0.00 sec)

Björn