Issue TTFB increase from 0,2s to 1,8s within hour

[Digitree]

Server operating system version

Debian 10

Plesk version and microupdate number

18.0.65 Update #2

Dear all,

we are facing issue with TTFB on our server. Once we restart server and process this command via CLI

"curl -s -w '\nLookup time:\t\t%{time_namelookup}\nConnect time:\t\t%{time_connect}\nSSL handshake time:\t%{time_appconnect}\nPre-Transfer time:\t%{time_pretransfer}\nRedirect time:\t\t%{time_redirect}\nStart transfer time:\t%{time_starttransfer}\n\nTotal time:\t\t%{time_total}\n' -o /dev/null Rodinné včelařství Úůll"

we got TTFB 0,2s but within few minutes TTFB starting to increase and after one hour we are getting TTFB 1,8s and our web's starting to be really slow. I have increase RAM and CPU (44GB and 16CPU) but this didn't help. Could you please help? After restart everything goes well but within few hours its starting to go down....

Many thanks in advance
Josef

 

[Raul A.]

Hi,

How is php run, FastCGI or PHP-FPM?

Proxy mode enabled?

 

[Digitree]

Hi Raul,

thank you for reply. Its Dedicated FPM application served by nginx. And yes, proxy mode enabled. The main issue is that after reboot its quick as flash... after few minutes / hours, its going slower and slower. I have tried disable DDOS deflate plugin, Sitejet builder, Softaculous, but its still the same.

Josef

 

[Raul A.]

Can you share the FPM settings? Number of max_children, max requests, idle timeout and Fpm mode.

I suspect your php processes might have a memory leak, which causes the slowdown, and it gets cleared with a service restart.

 

[Digitree]

Hi Raul,

i have found the issue. The firewall was caused it. When I dissable firewall everything was quick as flash! I had installed DDOS plugin which add to ipatables around 3K rules and after I dissabled this plugin and clear iptables, everything is good now. Thanks for support.

Josef