Sudden rise in Ram usage, is this normal?

[DoctorX]

Hello,
Sometimes i come to check my statistics about resources usage in my server.
Normally, Iam using about half my ram.
But i found (in the graph of ram usage) that the usage suddenly rise to use all the available ram and then within few seconds the ram usage return to the normal range.
Does such behavior is normal, or there is a problem in the server?

Thanks

 

[accyuklad]

maybe to many vistors at a certain time

 

[DoctorX]

I don't think that visitors are causing this.
My visitor count are not changing too much during the day.
Even if we suppose that the visitors really increase at certain time, does this explain using double amount of ram? and then suddenly within seconds return to normal value?

 

[accyuklad]

well cant be ddos as your cpu would spike im sure someone will have a idea you not searched on google

 

[Lock Down]

You didn't say what software like ipb, vb or ?? You were running but mysql if someone does a large search of anything can use memory fast. And if a few people do that it will easily eat all available memory for a short time.

So yes you can call it normal if that is what is happening. Use top and watch what program is doing it.

 

[DoctorX]

Iam using Mybb.
Now i have disabled search in the forum.
Lets see what will happen.
Thank you.

 

[Lock Down]

You are welcome. Keep us posted.

 

[Intrusion]

Sounds like a small syn flood to me.

 

[NewEraCracker]

Are you using MySQL 5.0? If yes, you are advised to upgrade to 5.1.

 

[Rew]

signs of search queries (surely) or heavy read/write in DB ( not seems in your case)

 

[AndroidApps]

Check your MaxClients setting in /etc/apache2/apache.conf just in case.
You can also check the amount of connected clients:

watch -n 2 "ps aux | grep apache | wc -l"

On one of my boards increasing the search interval helped tremendously.

 

[masterb56]

Xen vps?