Ruby on rails 慢动作

我在Rails中的动作很慢。view/active record和sphinx都报告渲染速度很快，但整个操作大约需要1.2秒。一点也不好。我想知道这是否是因为我正在将一个大型活动记录集转换为JSON。这是我的日志输出

Started GET "/genres/popular?page=2&per_page=10" for 127.0.0.1 at 2011-05-17 17:53:04 +1000
[Barista] Compiling all scripts for barista
[Barista] Compiling all coffeescripts
Processing by GenresController#popular as JSON
Parameters: {"page"=>"2", "per_page"=>"10"}
Genre Load (0.5ms)  SELECT `genres`.* FROM `genres` ORDER BY medias_count DESC LIMIT 10 OFFSET 10
SQL (0.3ms)  SELECT COUNT(*) FROM `genres`
Media Load (2.2ms)  SELECT `medias`.* FROM `medias` WHERE (`medias`.genre_id = 209)
Genre Load (0.2ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
MediaType Load (0.2ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 209) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
Media Load (3.7ms)  SELECT `medias`.* FROM `medias` WHERE (`medias`.genre_id = 14)
Genre Load (0.3ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 14) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
Media Load (2.0ms)  SELECT `medias`.* FROM `medias` WHERE (`medias`.genre_id = 286)
Genre Load (0.3ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 286) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
Media Load (2.0ms)  SELECT `medias`.* FROM `medias` WHERE (`medias`.genre_id = 264)
Genre Load (0.3ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 264) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
Media Load (2.0ms)  SELECT `medias`.* FROM `medias` WHERE (`medias`.genre_id = 270)
Genre Load (0.3ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 270) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 270) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 270) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 270) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 270) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 270) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 270) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 270) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 270) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 270) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
Media Load (2.0ms)  SELECT `medias`.* FROM `medias` WHERE (`medias`.genre_id = 271)
Genre Load (0.3ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 271) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 271) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 271) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 271) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 271) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 271) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 271) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 271) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 271) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 271) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
Media Load (2.1ms)  SELECT `medias`.* FROM `medias` WHERE (`medias`.genre_id = 36)
Genre Load (0.4ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 36) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 36) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 36) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 36) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 36) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 36) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 36) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 36) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 36) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 36) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
Media Load (2.1ms)  SELECT `medias`.* FROM `medias` WHERE (`medias`.genre_id = 58)
Genre Load (0.4ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 58) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 58) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 58) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 58) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 58) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 58) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 58) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 58) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 58) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 58) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
Media Load (2.2ms)  SELECT `medias`.* FROM `medias` WHERE (`medias`.genre_id = 186)
Genre Load (0.4ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 186) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 186) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 186) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 186) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 186) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 186) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 186) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 186) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 186) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 186) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
Media Load (3.4ms)  SELECT `medias`.* FROM `medias` WHERE (`medias`.genre_id = 10)
Genre Load (0.3ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 10) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 10) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 10) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 10) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 10) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 10) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 10) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 10) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
CACHE (0.0ms)  SELECT `genres`.* FROM `genres` WHERE (`genres`.`id` = 10) LIMIT 1
CACHE (0.0ms)  SELECT `media_types`.* FROM `media_types` WHERE (`media_types`.`id` = 1) LIMIT 1
Completed 200 OK in 1262ms (Views: 209.9ms | ActiveRecord: 28.2ms | Sphinx: 0.0ms)

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是的，我只是需要加载媒体。Rails 101.

这是一个很大的SQL语句。您是否考虑过在AR查询中使用：includes=>'genres'。你能发布你的动作控制器代码吗？是的。在加载类型时，我也停止加载所有相关媒体，我正在重写唯一依赖于该行为的项目。这比任何事情都要快，因为我正在用JSON处理25000个数据（并将其发送到客户端！！！）