@Ghany
I have no idea why it is going down, but there is no error in your logs so you need to work with hosting provider.

Now working fine, still i dont know why i faced such a issue

@bickja.com

you have issue with alert system, not only you i too have, alert system consuming more resources
for example for total template we are using 100% resource of server.
but only for alert system  we are using 250% resources its leading to server going down. means for this we want a dedicated server....

check your error http://prntscr.com/g041nw


@frostick
sorry to asking once again, i am facing different types of issues in alert option
1. getting same listing trice http://prntscr.com/g049sx
2.if we unsubscribe listings in alert option was empty, but issue was when i am subscribing again i am getting old listings again on alert option.
3. server going down only when user using subscribe option here http://domain.com/searcher  after getting some alerts in profile
bro sorry for irritating you again and again.thank u

@Ghany
Alert system is osclass feature, not theme one. It cannot be fixed on theme level.

1) Not theme issue, check plugin compatibility
2) It does not make sense, you cannot unsubscribe items from empty alert.

I have posted this topic on forum
https://forums.osclass.org/general-help/alert-option-loading-very-slow-making-site-server-down-for-1minute/new/?topicseen#new

Aficionado replied to me
You have a FATAL error:

PHP Fatal error: Call to undefined function veronika_draw_item() in /home/classibo/public_html/oc-content/plugins/related_ads/related_ads.php on line 10

that (i guess) come from your THEME.

Can you please check it once?
i have contacted some other osclass developers but they could not able to trace this error,
please try to help me in this issue.
Thank you

@Ghany
When plugin used on veronika it is not undefined:
oc-content/themes/veronika/functions.php

function veronika_draw_item($c = NULL, $view = 'gallery', $premium = false, $class = false) {
  $filename = 'loop-single';

 ....


anyway undefined function error imediatelly returns error.

@frosticek

I really not understand what should i have to do now,

can you please help me more here in clear way?
I appreciate the time you have spending on this issue.
thank you

@Ghany
I do not think you can find root of problem, try to check long running queries on database.

in mysqld.log i have only one error

170820  9:26:59 [ERROR] Incorrect definition of table mysql.proc: expected column 'comment' at position 15 to have type text, found type char(64).

in msql process i have seen that

oc_t_item.*, oc_t_item.s_contact_name as s_user_name
FROM (oc_t_user, oc_t_item)

taking more time 130+

@Ghany
It seems to be corrupted query. Look on it, you get 2 tables into select, but get data just from 1 table. More there is no connection between these 2 tables that can lead to cross join (something like full outer join without key) if query minification is not enabled. Try to find what is using this query.

I.e. if it is used just on alerts page (you can see it in db debug when logged as admin), try to eliminate block of codes what is function that cause this.