how to measure performance of IPS board (numebr of users) before going to Production?

[yurone]

we are in process of bringing to life new FORUM (IPS Board obviously).

1) is there a way to "test drive" / "measure performance" the charge and speed of the board before going to production?

how do you usually do it ? i interested how many user can in handle.

2) can jmeter help with it (i don't have any experience with it, so a tutorial would be useful)?

p.s.

for now it is planned to be hosted on a "low cost" shared host (8eu/month dreamhost)

but we are considering of cloud hosting (digital ocean or linode)

[Grumpy]

First, an answer to which you seek. But be sure to read the end too...

There is no certain way to know, since lot of everything is based on assumptions.

You can use load testing tools like jmeter to test this. jmeter is fairly advanced though, and you may choose to do a simpler bench like apachebench (ab). With ab (after installing), you just write "ab -n 500 -c 50 http://yoursite.com/". Doing so will request that specific address 500 times with 50 concurrent requests. This simulates 50 users hitting some page simultaneously (defined within response period) for 500 times. This is a lot more than you are likely to get. Because you need to think that 50 real people don't hit pages at the very same time. If a processing takes 0.1 seconds and each user looks at a single page for 60 seconds each, that means to fill up a constant 50 requests, you need 6000 people. As you can see, how "simultaneous" is defined makes a huge difference. IPS's definition of simultaneous is usually unique ip over 15minutes. Like here.

Of course, getting the math right is more complicated since the processing time would be a function of requests. Also, this does not test for your all other files, just that ONE page which a real user would create.

So really, just think of it as a very very rough idea of the load. And I suppose interpreting the result is a question of it's own.

Now, having said that...

DO NOT RUN ANY HEAVY BENCHES ON SHARED HOSTING. DO NOT RUN ANY HARDWARE TESTING BENCHES ON VPS/CLOUD.

Those things are shared resource. You hogging the resource to see the maximum performance means you drag everyone else down with you. Every site, application, etc. hosted on that physical server will slow down because of you. It's also a quick way to get thrown out of your server for ToS violation.

So, rather than testing what is the maximum capacity, think of what is reasonable to run, and see if you can run that.

Benches are also a bit meaningless on any sort of shared hardware because it fluctuates a lot. Enough to make it pointless. You could be pushing out 1000 pages/s right now, but it doesn't mean you can do that tomorrow. Some other person might hog the resources and you may not even get 1pg/second. Getting a good host also largely means you get a host that manages these resources well so that there's no hogging by one/few user.