What on earth is wrong with texture downloads?

Ok, it seems over the past few months, the performance of SL has gotten worse and worse. Now, when I teleport anywhere, it can sometimes take up to 10 minutes for all the textures to fully render - and I am on a 3 mb DSL connection. Other people I talk to have the same problem - some stuff will render quickly, others stuff often won't come in at all. What is going on? It has made SL pretty annoying of late - half the time all I see are odd transparent textures all over everything. Ever since version 1.5, it seems that the performance of SL has just plummeted.

I have weird issues with texture loading like that as well. I addition, attachments that won't detach or attach also have been driving nuts.

hmm, I do have this same problem in "some" areas... And I notice people have problems in areas I DON'T have a problem with, I am wondering if it has something to do with our own personal cache's? For example... when I log in at Le Cadre, my draw distance is usually at 320 so I can see Le Cadre and Eclipse, and it takes about .5 seconds to see everything clearly... but when someone else comes to Le Cadre... they are like "waiting for everything to rez" .... *shrugs*

I don't have a problem in my own sim - this is when I go to a new area - it just seems the download times have gotten crazy of late to render the textures, even on really fast connections.

Does SL compress textures at all?

Yes that was my point Cris, I dont have a problem in my home sim either, but others do...

LOL. Now that would be quite a strain on the servers if SL was streaming around uncompressed TGAs
You may be joking, but in case you're not:

SL uses JPEG2000 compression for all textures, which is probably the best format currently available for photo-like (high color / complex) images. I'd still like to see a png option for select low-color "vector-like" textures though.

Here's an jpg/jp2 comparison:
http://nirvana.informatik.uni-halle.de/~ritter/Seminar2002/klapperstueck/

Back on topic:
What seems really strange to me is that, if I relog into SL and see the sheep I worked on before logging out in front of me, it looks as though its textures are streamed back to me. Shouldn't they be somewhere in my 1 GB SL cache?

I have noticed the same thing - often times just moving around the same sim - textures that should be in my cache are redownloaded. I have removed SL, switched computers, even switched internet connections, and it has been the same effect - other people have similar problems. It seems somewhere along the way with the asset server "upgrades", the download speed of textures to a sim has been severely crippled. What is even worse is prims without a texture are invisible instead of solid - the whole effect is very unpleasant. I first noticed it about 2-3 months ago, and it has gotten worse with each update.

I've noticed the same thing over the same period. This texture slowness doesn't appear to be accidental "lag" but server side throttling as it will happen even when there is no sound or agents or anything that is trying to get to my machine. I can sink 500kbps+ when SL decides to send me such, but I can also stand on a half rezzed parcel, with no network activity (and thus 0% packet loss).

Think of it as a variant of "waiting in login queue" that lets you see through/be eaten by walls. There are many such throttles in the server which allow them to tweak outbound traffic per customer. As the population has grown the degree of throttling has increased; usually with each release.

Cris,

I've noticed more and more texture abuse. Hit ALT+3 and look around... right click and EDIT some objects. Look at the ones highlighted in yellow (wait for the bar to turn dark purple... that means its loaded). Then look at the resolution. Tons of people are using 1024x1024 textures on 1 meter by 1 meter objects. UGH.

-Flip

Woah that ALT-3 thing is trippy, I've never used it before. While I agree people are using a lot of hires textures, there still is definitely something wrong.

Flipper I dont know if this is even possible, but I wonder if texture size can be a client option. Here is what I am thinking.

Say I upload a 1024x1024 texture for my 1x1 meter prim. The SL servers will store this texture and automatically resize and store every size increment down to, say, 64x64. Then YOU can set a "max resolution" option in your preferences. So say you are maxed at 256x256. While everybody else has to wait for the huge textures, YOUR client requests the the lower res, but speedy small textures.

Shtoopid idea?

Aimee, I've pondered that before, actually, and its definitely possible. Here's the problem... it would take up a huge amount of storage on the server.

I was thinking more along the lines of... if you upload a 1024 by 1024, it also creates 512x512, 256x256, 128x128, 64x64. The user idea is cool, but I was thinking Linden Lab imposed limits of 2 meters or less, 256x256 or less. 512x512 at least 4 meters by 4 meters. 1024 only for 8 meters by 8 meters and above.

Just thinking out loud here. It would require a lot more math on the server side, unfortunately, to calculate which texture to display for each prim.

The big downside for LL would be the storage problem... for every 1024x1024 texture uploaded, you'd also need to store a 512x512, a 256x256, a 128x128, a 64x64 and a 32x32. That's 5 additional images.

Still, I like it as an idea Maybe a dropdown for max texture size next to gestures. I'd leave mine at 256x256 unless in an area where I definitely wanted detail, then bump up to 512x512.

Exceptions would have to be made, of course, for animations use llSetTextureAnim, and so on.

Regards,

-Flip

Ya I figured hard drive space would be the issue. Good food for thought though.

Hmmm
how about this Client Side Sim Caches...for instance a Series of sims you frequent would have their own cache on your PC. This would allow for instantaneous rez in. Additionally Caches like this could allow for the aforementioned Texture Redux.

For instance if you decided that your average places were 256 x 256 the first time you loaded into that sim the Cache would have all 256 x 256 rendered pics. If you ever change it it would require a new download automatically mind you to the cache.


This would significantly reduce texture storage as the other 5 or so images would only be created by a querry when you entered that sim.

But anyway just an Idea.

Shadow.

The suggestions are great - though the larger question remains, what has happened?

Here is an example, after nearly 5 minutes in a sim:

Example # 2 - 10 minutes in the sim:

I think I may know what causes this in certain circumstances, Cris, but this is merely a guess.

It probably does NOT cover the cases you're talking about here entirely.

Recently the back end was changed to stream textures to sims from the asset server on request. In other words, after a sim reboot or a grid going up and down, instead of streaming textures from the asset server to all the sims at once, they request now goes:

(1) person is in a sim and needs textures... they are requested from the sim
(2) the sim doesn't have the textures... they are requested from the asset server

This prevents a huge, huge traffic jam at the asset server... somewhat. Its the same reason it takes so long for textures to appear after a version upgrade.

Once sims are locked to their respective servers, this will be less of a problem. When the grid comes up, you'll be on the same server as before, which will already have the textures cache'd at the sim level.

So that's one problem. As for what's causing this... it may be related. I'm sure performance problems from swapping sims must exist.

-Flip

Yeah, I don't think this is a universal problem Cris.

I happen to experience this once in a while, but never consistently which rules out it being a sim problem. Considering the volatility of UDP packets, could it be possible that it's a transmission fault? Maybe happening at the sim -> asset server or sim -> you level?

Also, I think SL switched to culling textures which means that it streams in and loads up only the textures you can see atm in order to preserve client-side resources.

Personally, I'm not the hugest fan of it as I can turn around for a second, then turn back and have to wait a few seconds to load up some of the bigger textures.

Merh.

I have noticed it seems to be much more prevalent in newer sims - for example, I went to a place in the sponsored links (the car dealership shown above) and had terrible results - I teleported to Stanford, and it came in pretty quickly. It is definitely not my connection - I have both a cable model and DSL from two different ISPs (don't ask) and notice no difference - also, I have talked to other people who have the exact same rendering problems.

I'll do my best to paraphrase...


so it seems that you and a group of other people seem to have this problem.

I really haven't experienced it that bad as shown in the photos (at least not for longer than 30 - 60 seconds). But I do experience the bad texture culling that the SL client uses now.

Mayhaps it could be an internal routing problem with some sims. It could be as simple as a router in the hosting facility dropping a few UDP packets along the way. I'll check out that sim myself sometime and just see if I experience it too.

My guess though is that it isn't LL's doing either accidentally or intentionally. I'm betting it's a network problem somewhere along the way.

Icon,

I spoke with Philip yesterday about it - he confirmed they are aware of it and see the problem themselves, that it is a pet peeve of his - the rendering performance has dropped over time in some sims as updates have been made to the software - a tradeoff of improving some other things. They are working to track down the problems. I am glad you are not experiencing it - it's rather unpleasant to be in a sim for 10 minutes with all the far away textures rendered, and nothing near you coming all the way in. I remember going to a fashion show that Paolo Portocarrero was hosting, and thinking to myself, why the hell is this theater transparent, this is ugly lol.

I must have been there for 15 minutes before all the textures fully downloaded. It detracts from the immersiveness of SL, and adds to the frustration of flying someplace (which by the time I get to I am normally pissed off from lag/getting stuck). I am not on a low end machine or a slow internet connection - I just miss the performance that SL once had - I look forward to it coming back. It does not happen in every sim, or all the time, but when it does happen, it is frustrating.

Why do you have two internet connections cris?

I got my cable modem as part of a cable package several years ago, and then switched to DSL when BellSouth started offering 3 meg service before my cable company. To show how screwed up cable pricing is, it would cost me more to get rid of my cable modem than to keep it - if I got rid of it, it would break my package and they would have to reprice on current rates - I would end up paying more for the same cable that I have now, without a cable modem. I keep it and use it for a VOIP line for business.