Web Hosting Talk : Web Hosting Main Forums : Web Hosting : Memory limit on shared hosting

[MTempster]

Hello.
I have read topic where memory limit was discussing. I didn't attach importance to that. I want to ask you about your experience with memory limit on shared hosting package.
Thanks.

[MrRadic]

Well its more than about memory limit. Most hosts really watch for the CPU usage, because thats the biggest disturbance for other customers.

[MTempster]

Originally Posted by MrRadic

Well its more than about memory limit. Most hosts really watch for the CPU usage, because thats the biggest disturbance for other customers.

Yeap I have heard about that. But how do they manage count that?

[Trinity70]

As I have heard there are some programs installed on the server for counting CPU usage.

[MTempster]

What are they? I'm interested how does it work?

[MrRadic]

Originally Posted by MTempster

What are they? I'm interested how does it work?

Well on Windows Server 2003 / Longhorn Server every site runs in its own process, and there is built in functionality to track or even limit sites to how much CPU usage it can use.

[thekiwiproject]

A lot of hosts simply use the cpu/memory status in WHM (if they are a cpanel host), though there are a number of 'scoreboard' like softwares that can be put in place. The only one I know off the top of my head is a perl module called Apache:coreboard. Most of these target a specific type of memory usage (mysql, http, etc). Shell access an also have memory limitations so running things like fcgi processes can conflict there.

[mripguru]

Originally Posted by thekiwiproject

A lot of hosts simply use the cpu/memory status in WHM (if they are a cpanel host), though there are a number of 'scoreboard' like softwares that can be put in place. The only one I know off the top of my head is a perl module called Apache:coreboard. Most of these target a specific type of memory usage (mysql, http, etc). Shell access an also have memory limitations so running things like fcgi processes can conflict there.

.... and those stats are highly inaccurate.

[thekiwiproject]

.... and those stats are highly inaccurate.

Painfully so in fact, however this is still a common metric. If you want to know for sure it is always best to ask your host what they use specifically.

[MonteCarloHosting]

Most hosts I know invoke phpSuExec/SuExec which shows the processor and memory utilization of a specific username, and go by that. But, as previously explained, the numbers aren't always correct, and can cause unnecessary head-aches if the host doesn't know _exactly_ what he or she are looking at

[utropicmedia-karl]

Originally Posted by MonteCarloHosting

Most hosts I know invoke phpSuExec/SuExec which shows the processor and memory utilization of a specific username, and go by that. But, as previously explained, the numbers aren't always correct, and can cause unnecessary head-aches if the host doesn't know _exactly_ what he or she are looking at

Agreed, however, the numbers are HIGHLY accurate, as they are generated by the Kernel.(proc)

[vantage255]

The most accurate system out there is standard unix process accounting. The problem is, it is done on a per user basis, so it generaly doesn't include the apache user time in its totals.

In general, Most hosts use instantanious data more than they use any actual time based recording. So they will often give the boot to whoever is killing the server at the time that there is a problem, as opposed to watching cpu/mem use over time.

[MonteCarloHosting]

I should have explained myself better, karl. I've seen some hosts go bananas because they monitor top, which shows a PHP process using 68% CPU at the moment. Like vantage says, you need to go over a greater period of time

Regards,
Christian

[utropicmedia-karl]

Originally Posted by MonteCarloHosting

I should have explained myself better, karl. I've seen some hosts go bananas because they monitor top, which shows a PHP process using 68% CPU at the moment. Like vantage says, you need to go over a greater period of time

Regards,
Christian

I agree 100%.