Debug Setting 'MeshMaxConcurrentRequests'

[LittleMe Jewell]

From recent forum discussions I have learned that what I was told by vendors years ago - set LOD to 4 - is bad and if actually needed it means the product is not made well.  I've also learned about all sorts of other settings that can hamper or help my SL experience.  Now I'd like to know if setting 'MeshMaxConcurrentRequests' to a higher value is helpful, harmful, or doesn't necessarily make lots of difference?  I had a vendor say to increase that setting to 33 or higher to get hair to load faster and to help prevent it from disappearing when you TP.  Curious as to whether that is good advice or something to be avoided.

[Theresa Tennyson]

16 minutes ago, LittleMe Jewell said:

From recent forum discussions I have learned that what I was told by vendors years ago - set LOD to 4 - is bad and if actually needed it means the product is not made well.  I've also learned about all sorts of other settings that can hamper or help my SL experience.  Now I'd like to know if setting 'MeshMaxConcurrentRequests' to a higher value is helpful, harmful, or doesn't necessarily make lots of difference?  I had a vendor say to increase that setting to 33 or higher to get hair to load faster and to help prevent it from disappearing when you TP.  Curious as to whether that is good advice or something to be avoided.

It's terrible advice and they changed that function anyway so it won't do anything anymore. Turning it up just sent a lot of requests to the servers, which may have helped when mesh was first introduced but it eventually got to a point that it would lag out the server and mesh still wouldn't load sometimes.

[Chic Aeon]

I actually used that a couple of years ago MeshMaxConcurrentRequests and it helped a lot -- by turning it DOWN.   There was one sim in particular that I crashed in often. By turning it down (that was when I had my LOD set at 4 not the 2 it is now) it stopped me crashing. I think a combo of the two was my downfall. That was an older and less powerful machine. 

If I creator tells you that you need to do something major (in the debug settings ^^) to get their items to work, then to my mind they aren't very good products LOL.   Even everyday things should look OK for folks not using higher setting. They won't look as good as they CAN of course (well many times) but they still should be acceptable for viewing. 

That's my opinion anyway. Very happy you worked out the LOD stuff :D.  

 

[ChinRey]

10 hours ago, LittleMe Jewell said:

Now I'd like to know if setting 'MeshMaxConcurrentRequests' to a higher value is helpful, harmful, or doesn't necessarily make lots of difference?

I think Theresa knows more than me about this but I believe that setting became irrelevant when data transfer was switched to the http (Hypertext Transfer Protocol).

When your computer downloads assets from the server, it doesn't do it one at a time but several in parallel. The transfer protocol SL used to use (and apparently still uses for some assets) can't handle that very well so they had to put a limit to how many open transfers there could be at any given time. That is what the MeshMaxConcurrentRequests does. Http has no such problems so that setting should make any difference anymore. The ideal solution for SL would actually have been a kind of ftp/http hybrid - that is http without the web page specific headers - but implementing a brand new custom transfer protocol would be a huge undertaking and http is close enough the improvement would have been marginal.

 

10 hours ago, LittleMe Jewell said:

From recent forum discussions I have learned that what I was told by vendors years ago - set LOD to 4 - is bad and if actually needed it means the product is not made well.

Strictly speaking it's not the value of the LoD factor that is the problem, it's the lack of a consistent standard. A scene in Second Life will only perform at its best if every single item in it is optimized for the same LOD factor. Prims are always optimized for LoD factor 1 and Linden Lab originally went to great lengths to maximize their performance the prim shapes to that setting (except they messed up the plain cube badly, that one is actually optimized for LoD factor 0). When they introduced sculpts, they messed LoD up reallly bad and sculpts are not really optimized for anything. Good sculpt makers eventually found ways around that mistake but not everybody got it and the trick of increasing the LoD factor to basically disable the LoD system was born. (I'm always a bit sad when I talk about sculpts because they're a textbook example how poor implementation can ruin a brilliant idea.) Meshes can of course be optimized for any LoD factor but unfortunately LL didn't learn from the sculpt blunder so they messed it up again.

Edited May 24, 2017 by ChinRey
typos

[Whirly Fizzle]

MeshMaxConcurrentRequests is deprecated & is no longer used.  Changing that setting will not do anything on SL grids.
The "new" setting is Mesh2MaxConcurrentRequests.

Cranking up the Mesh2MaxConcurrentRequests setting these days is just as bad advice as cranking up MeshMaxConcurrentRequests was back in the day.

Relevant info:

• FIRE-11451 - Cap MeshMaxConcurrentRequests at some sane value
• http://community.secondlife.com/t5/Second-Life-Viewer/avi-dosn-t-load-correctly/td-p/2137193 <--- @Monty Linden explaining why setting MeshMaxConcurrentRequests higher is a bad idea - " Please tell me 500 was a joke. That would make me cry..."
• http://www.youtube.com/watch?v=OrHlYMlZhZk <--- TPV meeting where @Monty Linden explains about the then upcoming caps viewer & serverside. Start at about 18.30 for relevant info.

Edited May 24, 2017 by Whirly Fizzle

[ChinRey]

THis is how many people want to run Second Life

and they can't understand why it's so slow.

 

[Phil Deakins]

Brilliant, ChinRey

[LittleMe Jewell]

4 hours ago, Whirly Fizzle said:

MeshMaxConcurrentRequests is deprecated & is no longer used.  Changing that setting will not do anything on SL grids.
The "new" setting is Mesh2MaxConcurrentRequests.

Cranking up the Mesh2MaxConcurrentRequests setting these days is just as bad advice as cranking up MeshMaxConcurrentRequests was back in the day.

Relevant info:

• FIRE-11451 - Cap MeshMaxConcurrentRequests at some sane value
• http://community.secondlife.com/t5/Second-Life-Viewer/avi-dosn-t-load-correctly/td-p/2137193 <--- @Monty Linden explaining why setting MeshMaxConcurrentRequests higher is a bad idea - " Please tell me 500 was a joke. That would make me cry..."
• http://www.youtube.com/watch?v=OrHlYMlZhZk <--- TPV meeting where @Monty Linden explains about the then upcoming caps viewer & serverside. Start at about 18.30 for relevant info.

Thanks much for the various links - gives me a lot of good background on things.

[HaileeTempesta]

I was told to go into debug settings and set my LOD to 8.  Everything looks fine for me with it at that setting and SL hasn't run slower or anything that I've noticed and things that used to crumple at long distance viewing no long do.  Does the setting cause some damage somehow?

[Monty Linden]

On 5/23/2017 at 3:33 PM, LittleMe Jewell said:

Now I'd like to know if setting 'MeshMaxConcurrentRequests' to a higher value is helpful, harmful, or doesn't necessarily make lots of difference?  I had a vendor say to increase that setting to 33 or higher to get hair to load faster and to help prevent it from disappearing when you TP.

Any perceived improvement from playing with that setting is pure Placebo Effect at this point.  It isn't connected to anything in the viewer.  You can get a few more details in a nice little diagram in this old post:

https://community.secondlife.com/forums/topic/343472-meshmaxconcurrentrequests-does-anybody-know-the-real-setting/#comment-1112283

 

[ChinRey]

10 hours ago, HaileeTempesta said:

I was told to go into debug settings and set my LOD to 8.  Everything looks fine for me with it at that setting and SL hasn't run slower or anything that I've noticed and things that used to crumple at long distance viewing no long do.  Does the setting cause some damage somehow?

It can actually damage your gpu, although fortunately that is very rare.

Increasing the LoD factor willl increase your graphics processor's workload significantly. I have never heard of anybody using LoD factor as high as 8 - I didn't even know it was possible - but I would guess it would increase your gpu load with something between 100% and 300%, depending on the scene. That means you gpu either has to slow down and reduce the frame rate (how many times a second it redraws the image on the screen) or it will overheat and break. Fortunately it usually goes for option 1 but that is hardly ideal either. Most people will start to notice a quality reduction when the frame rate drops below around 40, others may be quite happy with 20. Below that, everybody will notice there is something wrong. If you use a VR headset, you are likely to get physically sick if the frame rate drops below 90 and that is why they had to give up on VR headsets in SL.

It is possible to compensate for the extra load by reducing the other graphics settings but you don't really want to do that unless you have to because keeping those other graphics settings high adds to the quality. The LoD factor does not, it's only about damage reduction, compensating for poorly made mesh.

The only excuse people have for making mesh that requires increased LoD factor is that you can get lower land impact that way. That is a truth with modifications. A skilled mesh maker knows several ways to reduce the land impact without reducing the visual quality and I have yet to see a single "high LoD factor" mesh that couldn't easily have been made with even lower land impact and no LoD issues if the maker had known what they were doing.

Edited May 25, 2017 by ChinRey
Editing

[LittleMe Jewell]

8 hours ago, Monty Linden said:

Any perceived improvement from playing with that setting is pure Placebo Effect at this point.  It isn't connected to anything in the viewer.  You can get a few more details in a nice little diagram in this old post:

https://community.secondlife.com/forums/topic/343472-meshmaxconcurrentrequests-does-anybody-know-the-real-setting/#comment-1112283

 

Thanks much for the response and info.

[Pussycat Catnap]

19 hours ago, HaileeTempesta said:

I was told to go into debug settings and set my LOD to 8.  Everything looks fine for me with it at that setting and SL hasn't run slower or anything that I've noticed and things that used to crumple at long distance viewing no long do.  Does the setting cause some damage somehow?

Anytime you set LOD to 4 or above, you are essentially turning OFF graphics optimization in Second Life. That means that things will look better even at distance, but ALSO that things you cannot even fully see will take up resources on your graphics card, slow you down, and even heat up your graphics card and CPU.

If you ever experience a moment in SL where you start seeing flickering triangles of black or white, and then suddenly crash... that was because of something like this being set to high for your situation, your system getting overwhelmed, and then giving up.

Even if you never experience that catastrophic failure... you are forcing that little card to work harder than it was designed to, and possibly shortening it's lifespan.

 

Reasons like this are why I set my:

LOD: 2.75

Mesh2MaxConcurrentRequests: 8 or lower

Complexity Maximum: 80,000