Hi,

Just had my 1536 Linodes up for testing and noticed and fairly low internal transfer rate:

getting a file across from newark116 to newark118 is averaging to about 5MB/s

I understand that there are may be 10-15 linodes running on the same server and fighting for the same gigabit port (by the way, is there just 1 interface on each physical server or dual?), but still, getting about 50mbps is somewhat on the low side of my expectations...

I was going to run Wowza Media Servers in a distributed network streaming live video feeds but having trouble estimating how many user I can sustain on one particular instance.

The question is - does Zen virtualization *guarantee* me at least <port speed>/<number of linodes on the server>? For example, if there's just 1 gigabit port on each physical server and up to 15 linodes running, can I count on at least roughly 66Mbps sustainable bandwidth at any given moment?

Thanks!
Art

By default, each Linode's UPLOAD speed is capped to 50MB(it?)/s. Open a ticket if you need more.

50Mbit.

_________________
Disclaimer: I am no longer employed by Linode; opinions are my own alone.

Ah, that makes sense, thank you!

Now, it is true for all linode types? I mean, even for 4GB, 8GB or even 20GB ones?

Art

Indeed it is. It's a safety valve for a few reasons. If you can demonstrate that it is preventing you from using your Linode to its full potential, we can raise it with a ticket.

_________________
Disclaimer: I am no longer employed by Linode; opinions are my own alone.

The reasons for the safety valve being there are best demonstrated with the calculator:

http://www.google.com/search?hl=en&q=20 ... 0+Mb%2Fsec

follow-up question then - am I guaranteed these 50Mb/s? I mean, if somebody on the same host requests a speed increase, how is it handled? Basically, do you oversell port speeds?

Thanks!
Art

You don't need to worry about being able to achieve 50Mbit/sec outbound into our network. However, we aren't in control of the entire Internet, so once it leaves our network there are no guarantees.

-Chris

Oh, no, of course I'm not asking to have guaranteed 50Mb/s stream somewhere from the server

I'm talking about reliably sustaining about 200 256kbps video streams per linode

the question was - if there are 20 linodes on a host and everybody requests 100mbps uplink it is clearly not possible with a single gigabit port...

Thank you!
Art

This never happens, but I'm glad you understand the architecture.

-Chris

Please move my VPS off his server

I really doubt it'll be a problem, but keep in mind that sustaining 200x256Kbps (50Mbps) would be ~16TB/mth, which would result in a rather hefty bill from Linode!

At that point, though, you would want to negotiate bandwidth pricing directly with Linode anyhow.

don't worry, guys,

- I'm well aware of the bandwidth, all I need is to know the limits, 200 viewers might hit 1 instance once in a year for a couple of hours. and knowing this, I still need 5 instances if I'm running a potential 1000 viewers event

- Second, vonskippy: what are you worried about? the live streaming takes just a bit of CPU and 200 users will hit 50mbit/s a second = less than a gigabit divided among all users... Everybody wants to be on the server that has nothing else going on, unfortunately, that's not the case with VPS some times... moreover, Xen will not let me use any more resources than allocated, so whatever your plan is, you'll get at least that for sure

For the record, I had sustained a couple of thousand live streams over a gigabit connection on a single server without a significant hit to CPU/memory. That's why I'm looking at cheaper VPS options so if I need more, I can get more for the moment and not overpay in day-to-day scenarios

Not worried about CPU, worried about I/O, and that depends on the XEN setup that Linode uses.

Do they do I/O Scheduling AND I/O Throttling - or just Scheduling?

Don't really look forward to sharing a box with you and having my MySQL thru put slow to a snails pace.

In order for VPS to work well, all the players have to be fair minded. Get a few "I'll use whatever I can wring out from the system" players - and the whole thing FUBAR's quickly.

Hmm, but my point is that you shouldn't suffer because of other instances...

BUT, it really depends on what you call "suffering" - if you do the calculations, a "fair share" of 16 2.5GHz CPU cores divided among 15 instances gives you just about a single-core 2.5GHz processor, which, in itself is not a terribly fast server. 1024 instances are even more cramped... As for other resources, like disk and net I/O - same thing, you are in line for your 1/15th (or 1/20th even) cut of the whole pie. Be it all MySQL databases or net streaming, it is not a fast server. Nor it should be at that price.

UNLESS other instances are not doing much...

If the whole reason you went for a cheap VPS was because you counted on it being underused then there it's a problem... I went there because I am fairly positive it will handle the load even if it's fully used. Sure, I'm going to get my money's worth but if Linode finds it abusive, oh well, I'll upgrade or leave, depending.

Sorry to come off like that, though, I'm actually a nice guy
Art