server-bandiwth capabilities & performance

[pitu]

This question is not about dathorn servers but in general....

let' say you have a dedicated P4 3.6, 2Gb Ram, 100Mb bandwith
and you need to let people download files...like large files about 20Mb (through simple links - passthrough php scripts)

How many users could the PC take at once?

For my project it is critical to the customer that 1000 users could download
at the exact same moment, exactly the same file, at a speed >600Kb/s if their connection allows it...

Obviously one 100Mb link could only hold lets say 200 simultanious downloads... but I was wondering if the PC could handle that ..... without blocking..restarting...depassing its RAM or something...

Any oppinions or real-world examples on that?

pitu

for info why do i need this:
it is for a site where people should be able to download mp3's (legally ofcourse )

[AndrewT]

You did not apply the proper conversions (bits to bytes). In your example you've used a gigabit connection.

100Mbps will give you ~12,500KB/s of upload at most. Divide that by 1000 - not a chance in the world of maintaining 600KB/s or anywhere near that. Divide it by 200 simultaneous downloads and you're still not anywhere close to 600KB/s (more like 60KB/s).

Other than that, downloads require minimal system resources. The only possible problem would be your PHP script that is handling the downloads.

[pitu]

Andrew thank you for your answer...

...I was thinking about Kbits and Mbits everytime it was marked kb or Mb...

So in your oppinion a server could serve 1000 users at the same time; with the bandwith proportionaly slowing for everyone..without any particuliar difficulty....

if that is the case... the solution would be to have enough bandwith like 600Kbit *1000 = 600 Mbit/s ....or maybe a connection that could burst to that speed for certain amount of time... but 600Mbit/s seems enormous....
could you propose me a service that offers that kind of bandwith ?

The php scripts would be simple:
test user pass
if ok then
fopen ($file)
fpasstrhu ($file)
that should'n normally be a problem if only fopen or fpassthru don't put all
the file in the RAM...

[AndrewT]

600Mbps is indeed enormous, you would want to find a realiable provider that can offer you a full gigabit (1000Mbps) connection. I'm sure The Planet could set this up for you, but it will certainly cost a nice chunk of change. At a sustained rate of 600Mbps you are using 4.5GBs of bandwidth every minute.

Allowing a 600kbit/sec download is only giving each user an actual download speed of 75kbytes/sec (your download dialogs in web browsers generally display in bytes, not bits). Most cable/DSL connections are much faster than this.

[Amitabh]

Sorry for getting in between, but wouldn't large file transfers time out PHP scripts.

On a side note, if it's only download that you want, you might take a look at http://www.lighttpd.net/ . It's supposed to be lighter on the system resources.

[pitu]

..I was more worried as to wheather php scripts put the files in RAM before they send them..which would spoil everything...

i never thought of time-out..probably it would, but it can be configured...

thanks for your advice of web server, files are going to be 'just' downloaded but it has to go through scripts so as to check the id & permissions of each user.

[Amitabh]

Assuming that you are using either PHP for your script, it is supported by Lighttpd.