What is the max bandwidth speed default used by secondlife servers. Is it 1500 Kbps, 3000 Kbps?

[Rolig Loon]

The debug setting ThrottleBandwidthKBPS, which sets the Max Bandwidth, defaults to 500 kB/sec.  I have had mine set there for ages.  The recommendation that you may be remembering is that you should never set it higher than about 75% of your measured download bandwidth.  For many years,that averaged to about 1500 kB/sec for most people, so that's what we recommended.  These days, it has probably crept higher. 

The rationale for that 75% number is that the Maximum Bandwidth is determining the amount of bandwidth that your viewer can commandeer for its own use, reserving the other 25% for services (voice and streaming media) that also need bandwidth but could otherwise be starved.  If you set Max Bandwidth too high, voice and streaming media will cut out in high demand situations.  In practice, that rarely happens these days, since your viewer rarely needs more than about 500-700 kB/sec and most people have way more bandwidth to spare.  In other words, it doesn't really matter whether you set yours at 1500 or 3000.  Both are way higher than they really need to be and well below what will be limiting for most people (unless you have an ancient dialup connection, I suppose).

[Rolig Loon]

The debug setting ThrottleBandwidthKBPS, which sets the Max Bandwidth, defaults to 500 kB/sec.  I have had mine set there for ages.  The recommendation that you may be remembering is that you should never set it higher than about 75% of your measured download bandwidth.  For many years,that averaged to about 1500 kB/sec for most people, so that's what we recommended.  These days, it has probably crept higher. 

The rationale for that 75% number is that the Maximum Bandwidth is determining the amount of bandwidth that your viewer can commandeer for its own use, reserving the other 25% for services (voice and streaming media) that also need bandwidth but could otherwise be starved.  If you set Max Bandwidth too high, voice and streaming media will cut out in high demand situations.  In practice, that rarely happens these days, since your viewer rarely needs more than about 500-700 kB/sec and most people have way more bandwidth to spare.  In other words, it doesn't really matter whether you set yours at 1500 or 3000.  Both are way higher than they really need to be and well below what will be limiting for most people (unless you have an ancient dialup connection, I suppose).

[Nalates Urriah]

The default is 500kbps. The best setting from extensive testing by the Firestorm team is either 80% of your maximum rated download speed or 1500kbps, whichever is smaller.

The Max Bandwidth setting only affects the UDP protocol. Update information travels on the UDP protocol. Almost everythng else now uses the HTTP protocol. UDP has no error correction or lost packet recovery, HTTP does.

If you use your system's or other tools and watch the viewer stats, you'll see data coming into your computer at different rates. That is because the viewer only needed to know how UDP was preforming, so that is what they show. With HTTP it isn't issue. So, the viewer's bandwidth settings are not much use.

The setting doesn't actually affect the viewer. The value is sent to the SL region server and the server adjusts how much information it throws at your viewer. For this reason the setting is a combination of what gets you the best performance and what is best for a crowded server (crowded = lots of avatar).

[Shamara Henley]

Sound like what i know. Thank you!

[Shamara Henley]

Sound like what i know. Thank you.

[Whirly Fizzle]

As far as I'm aware the server ignores any Maximum Bandwidth setting over 3000 Kbps.

You can see this actually in the viewer log when the throttle kicks in.  If you set Maximum Bandwidth higher then 3k, the throttle readings in the log never go above 3k.

Couple of relevant JIRA issues:

SH-3149 - (Monty thoughts?) Lower max selectable bandwith to be in line with the max of the server

VWR-29029 -  unexpected behavior with UDP throttling when bandwidth is set higher than 1900

[Shamara Henley]

Thank you, that make lot of sens with what i know. I appreciate.

[Bobbie Faulds]

Actually, you don't need your bandwidth set any higher than around 1000. Much higher than that doesn't really help. Think of it this way. SL sends out the data at a max rate, equivalent to a full 1 inch pipe. You can attach a 3 inch pipe but you'll actually get lower pressure. However, if you attach a 3/4 inch pipe to the 1 inch, you'll get more pressure. 

I have a really good rig and cable internet. I RP in a sim with a combat meter. I have my bandwidth set at 800 and almost never lag.