Safe Value for Memory Soft / Hard Limit ?

[semprot]

My current RAM is 24GB.
I use APC alot, i set the shm_size to 7GB.
My memory soft limit : 15G
My memory hard limit : 15G

But every 5 or 6 days, RAM usage is peaked a lot (> 80%) and cause various WHM services failure (nameserver, exim, httpd, etc).
On daily usage RAM usage is low (< 50%). I was thinking whether the load is accumulated every day.

Do you think i should reduce the memory soft / hard limit to smaller number such as 9GB?
Should i leave a space between APC shm_size and memory limit, such as shm_size 7GB and memory limit 8GB?
Or should i use same APC shm_size and memory limit, such as shm_size 7GB and memory limit 7GB?

Thanks.

 

[NiteWave]

>Should i leave a space between APC shm_size and memory limit, such as shm_size 7GB and memory limit 8GB?

yes

php run suExec mode or nob-suExec mode or suExec Daemon mode ?

 

[semprot]

>Should i leave a space between APC shm_size and memory limit, such as shm_size 7GB and memory limit 8GB?

yes

php run suExec mode or nob-suExec mode or suExec Daemon mode ?

I think it is daemon mode, but please take a look on my configuration below.

Thank you.

 

[NiteWave]

the configuration looks normal

 

[semprot]

the configuration looks normal

What is the resource (especially RAM) usage difference if i use "suExec Daemon" as "Run On As Startup" / no selected option at all.

And how can i restart suExec Daemon? By restarting httpd only / lsws only / the whole server?

Should i lower the memory limit?

 

[NiteWave]

And how can i restart suExec Daemon? By restarting httpd only / lsws only / the whole server?

restart lsws, no need reboot the whole server.