Problem solved. My bad. I create some query in mu-plugins. I use php. & forgot about empty lines in php files. I delete all empty lines in my custom code. All work fine. I hope its helps somebody 🙂

Hello Calin. Thank you for your answer. I check Composer. All works fine. In theme panel System status no warnings or errors. But on site first line in rss & xml sitemap are empty -> https://www.dropbox.com/s/9fea04chy9nhwey/Screenshot%202019-05-27%2016.13.45.png?dl=0 xml -> https://www.dropbox.com/s/24ixzc5rdeq463b/Screenshot%202019-05-27%2016.14.53.png?dl=0

Hey man i have same trouble. Can you share solution of this problem?

I install Relevanssi plugin. its helps :).
Thank you.

Also, consider using a cache plugin and to improve the loading speed look the MySQL query cache: http://dev.mysql.com/doc/refman/5.1/en/query-cache.html

Not help this link 🙂 https://www.dropbox.com/s/wpbqz429ft0ytjb/Screenshot%202019-02-25%2015.05.07.png?dl=0
Can you be more specific how you use & what to cache query in mysql.

I disabled almost all…..

I am use cloudflare pro + zend cache. w3 total. its not helps much with problem with mysql. I try tune mysql query cache if you send here more details. Tnx.

Little bit investigation, seems to be query like this kill all :
SELECT SQL_CALC_FOUND_ROWS wp_posts.ID
FROM wp_posts
LEFT JOIN wp_term_relationships
ON (wp_posts.ID = wp_term_relationships.object_id)
WHERE 1=1
AND ( wp_term_relationships.term_taxonomy_id IN (44) )
AND wp_posts.post_type = ‘post’
AND ((wp_posts.post_status = ‘publish’))
GROUP BY wp_posts.ID
ORDER BY wp_posts.post_date DESC
LIMIT 0, 5

Google cloud. 8vcpu.60gb memory. ssd. php7.0/opcache/w3total cache/memcached/nginx
& 60 users online i i got this 100% cpu load https://www.dropbox.com/s/qxjd6pm4h3kyxh8/Screenshot%202019-02-24%2019.44.19.png?dl=0

its ridiculous. i have a lot of high load wordpress sites but this i see first time…Can you help me?

SQL_CALC_FOUND_ROWS did this.
https://www.dropbox.com/s/9ofl5x2x4x3mfn3/Screenshot%202019-02-24%2003.13.10.png?dl=0

any advice?
a lot of taxonomy & posts.

Hi. Tnx for answer.no i iam migrate from drupal…… i fix my problem in more complicated but simple way:). Topic closed.