How to always have a short server TTFB?

[gilles]

When I run my sites through GTMetrix, I sometimes see a short server TTFB and other times it's much longer, several seconds.
I do not understand why this is the case. It's as if there was some really long server startup time. This usually happens when no accesses have been done for a bit.

Any advice on how to get rid of this "warm-up" time?

 

[Cold-Egg]

May I ask if it happens when the cache is a hit or not? the solution is different.

 

[gilles]

Here is a site that does not use any sort of caching. One request shows 1.12 sec of waiting time, the other one 186 ms.

 

[gilles]

My understanding is that the difference is at least partly due to not having lsphp already running for the first one.
Is there a way to keep it running?

PS: I need a bit more time to generate traces for the other websites that use caching.

 

[Cold-Egg]

Hi @gilles ,

Please try to keep PHP process keepalive longer.
Under "PHP" tab, update "Max Idle Time" from "60" to "86400" (1 day)
https://www.litespeedtech.com/docs/webserver/config/php#extMaxIdleTime
so, PHP processes will be alive. It reduced PHP startup time.

 

[gilles]

Thank you, this helps.

How does this parameter interact with 'Connection Keep-Alive Timeout'?
What's the default setting for 'Connection Keep-Alive Timeout' and what's a good setting for it? I think Cyberpanel sets it to 1 second.
Is this setting moot in http/2 and http/3?