Server Capacity to Daily Unique Visitor ratio

Anyone have a rule of thumb?

[Phil_AM]

I'm doing some work on behalf of a client and expect to receive about 200,000 to 400,000 uniques a day. 10% of those uniques will upload/download up to 500kb's of info per visit.

Ballpark?

I was thinking two Dell 2850 servers with 60GB capacity each should do the trick...

[jtara]

I have no idea. Nor could anybody possibly give you an answer with the information you have given.

How many page hits does the average visitor make? Over what period of time? What software is delivering the pages? (Static HTML pages? PHP? What, if any, database is being used? What is the distribution of your daily visits? (Spread out evenly over 24 hours? Packed into a 4-hour peak?)

Look at other similar sites, and see if they say what equipment they are using. Prototype and benchmark.

There is no rule of thumb that can be applied with so little information.

Are all the visitors going to magically appear on Day One? If not, why decide on equipment up-front? Start with a rented dedicated server, or with a VPS. Don't rush the decision to get your own equipment. Scale up as needed.

If you need some guidance for a business plan... prototype and benchmark.

[Phil_AM]

Thanks Jtara. I'm a marketing guy, not a hardware person, thus my novice understanding of server capacity.

Guess I have a lot more questions to ask before I fill out the RFP!

[aspdaddy]

Definetley trial the app. Once you can seethe average user footprint and the stats for 100 or so users you can do the math. (Bear in mind, not all growth is linear and consider bottlenecks like NIC buffers, licence restrictions etc)

With a good data centre most of the cost is for management not hardware so upgrading servers once you are is not that costsly. But, even the entry level costs are high and hard to justify for small volumes of traffic so you might want to wait until its kicked off before moving it there, or negotiate :) . Its really just a cost dilema.

I'm a marketing guy, not a hardware person

try and meet with the hardware/architects at the data centre once you have trialled and have some data to present

[TXGodzilla]

The best advice you have received is to get the hardware/datacenter staff involved. This is not the time to pull a server model out of the air without considering the specs, network environment, incoming bandwidth and power requirements.

Without knowing what operating system you are running, webserver package, database, configuration info or datacenter infrastructure, it would be near impossible to offer a hardware recommendation.

Depending on the environment, you would have to select RAM, processor speed and storage based on the applications running on the server. The general rule of thumb is "as much as you can budget plus a little more". Without a well optimized server & applications, you could have 8GB of RAM and still have sluggish responses.

It is all about what those uniques are doing and what you are running on the server.