How many listeners can my hardware handle?

[dbp653]

I have a XP PC with 100 mb/s networking card. My ISP is giving me more than 100 mb/s upstream available to me. In theory what is the maximum number of Shoutcast users that I can service with this one PC?

I want to stream a popular college football game, and the athletics dept. tells me to figure for up to 2000 simultaneous stream users.

For example a 24 kb/s stream times 2000 users is 48 mb/s bandwidth needed? Figuring a 50% saturation on my equipment, allowing for reconnects and other unexpected things.

Or am I dreaming, what am I not figuring into this to service this many of users? i.e Hardware bottlenecks.

Does anybody have any experience in serving this many users?

I need any perspective you may have.

Thank you,
Darren

[DrO]

Originally Posted by dbp653

I have a XP PC with 100 mb/s networking card. My ISP is giving me more than 100 mb/s upstream available to me. In theory what is the maximum number of Shoutcast users that I can service with this one PC?

it really depends on the bitrate of the stream and how reliable the upload speed you're getting actually is.

Originally Posted by dbp653

For example a 24 kb/s stream times 2000 users is 48 mb/s bandwidth needed? Figuring a 50% saturation on my equipment, allowing for reconnects and other unexpected things.

the general rule of thumb is (listeners * bitrate) * 1.1 for working out the bandwidth requirement (is only rough since the size of in-stream metadata, admin page access, etc will all vary but that seems to be what has been used for many years now).

so in that example it works out as around 53Mb/s though it could be higher depending on how clients connect and how many client connections they individually make (has been known for some to make multiple connections over time).

Originally Posted by dbp653

Or am I dreaming, what am I not figuring into this to service this many of users? i.e Hardware bottlenecks.

you would also need to make sure that the hardware this is going to be running on can cope with it and you might have to for safety use 2 or more hosts and have a load balancer to control which DNAS clients get directed to (assuming you're not being listed in the Directory as load balancers can mess around with the Directory handling).

-daz

[dbp653]

Originally Posted by DrO

you would also need to make sure that the hardware this is going to be running on can cope with it and you might have to for safety use 2 or more hosts and have a load balancer to control which DNAS clients get directed to (assuming you're not being listed in the Directory as load balancers can mess around with the Directory handling).

-daz

This gets to my big question about how many listeners my hardware can handle.

Assuming everything else is "a go."

What is your experience in connecting hundreds or thousands of users to one stream, using only one or two PCs? At what point, user count, do you see problems in having only one PC providing the stream, assuming that the combined request is within the networking data requirements? What are the issues in providing streaming service from only one PC. How much better do 2 PCs perform vs. having just one? More thoughts please.

Thank you,
Darren

[DrO]

it completely depends on the hardware and what what other software is running on the machine(s) at the time and it's really not possible to give a specific xx clients per CPU Mhz or anything like that.


2000 clients on a reasonable dual core machine from a few years ago is viable (based on the hosts i'm looking at currently) but that's not going from no clients to a full load in a short time as is likely to be your scenario.


since the initial hit from everyone trying to connect is going to be the first problem that would cause clients to fail to connect which is why most SHOUTcast streams where 1000s of clients are involved will usually have multiple DNAS being used as it also means if something goes wrong on one machine then it doesn't take out everyone.


so personally i'd try to have at least 2 machines providing the stream though i'd hope others with more experience with such things will see & reply to this thread with their views / experiences.

-daz

[dbp653]

Excellent advice and thank you again.

I am going to give my new streaming service a try with two PCs with two separate IP addresses, listing both "Stream A" and "Stream B" on our athletics website, and see how it goes. One PC is a modern dual core and the other is a single core celeron, both running XP, and I will reply on how my experience goes. This service will go live in August.

If anybody else has more perspective to contribute, on high volume streaming, I would appreciate your input.

Darren

[dotme]

I can only speak to the v1 DNAS, but Windows did not cope well with thousands of connected listeners on v1 - not sure if the v2 handles it any better.

The problem was that the TCP/IP stack got unhappy serving that many clients at once, and CPU utilization went through the roof. Linux handles those kind of numbers with ease though.

The thing is, you won't know (until you need the capacity) if the hardware will buckle with Windows as an OS and thousands of connected clients so I'd definitely recommend the multiple PC approach.

You've got the bandwidth covered. No concerns there, especially with the 24kbps bit rate.

[idobi]

I can't speak for Windows machines, but on linux v1 hums along nicely with 2000 listeners @ 128kbps. When we've had a server go down, other servers take up the slack and have gotten as high as 3500 listeners without any issues. This is on a Core 2 Duo 2.66GHz machine w/ 2gb ram.

I've had one issue when we had a sever with an i3 processors where, unless the other cores were disabled, v1 process hit 80% at 900 listeners, and became unresponsive at 1500.

Other than that, I think your limiting factor will be your available bandwidth.

[voodoohippie]

I would not try and run a Shoutcast server from home for it would take up lots of bandwidth. If your on a shoe string budget I'd recommend this server for they are dedicated servers and you get more listeners and can broadcast @ 128K go to http://1000slots.tk and sign up.