Category: Simulator User Group

The following notes were taken from the Tuesday, June 17th, 2025 Simulator User Group (SUG) meeting. They form a summary of the items discussed, and are not intended to be a full transcript. The notes were taken from my chat log of the meeting. No video this week.

Meeting Overview

• The Simulator User Group (also referred to by its older name of Server User Group) exists to provide an opportunity for discussion about simulator technology, bugs, and feature ideas.
• These meetings are conducted (as a rule):
  • Every Tuesday at 12:00 noon SLT.
  • In text (no Voice).
  • At this location.
• Meetings are open to anyone with a concern / interest in the above topics, and form one of a series of regular / semi-regular User Group meetings conducted by Linden Lab.
• Dates and times of all current meetings can be found on the Second Life Public Calendar, and descriptions of meetings are defined on the SL wiki.

Simulator Deployments

• There are no planned deployments to any channels this week, only restarts.
• The stall in simulators releases should be ending soon. It has largely been the result of:
  • Mainly a back-end move from one cloud asset store to another.
  • Coupled with continuing work on setting up github actions to build, store, deploy the various bits and pieces that run the SL backend services.

SL Viewer Updates

• Official Viewer: 2025.04 – 7.1.14.15192634334, issued May 25, promoted May 28 – No Change.
• Second Life Project glTF Mesh Import, version 7.1.14.15361077240 June 2 – No Change.
• Second Life Project Lua Editor Alpha (Aditi only), version 7.1.12.14888088240, May 13 –  No Change.

In Brief

• Rider Linden raised the idea of shifting the Simulator User Group meeting to once every two weeks.
  • This was considered fine *if* there were not a lot going on – and with the exception of last few weeks and the end-of-year slow-down, this generally isn’t the case.
  • Most of those at the meeting expressed a desire to keep it on a weekly basis, with one suggestion that if there is not a lot to discuss during any given meeting, it is brought to a close early, rather than always trying to spin it out to an hour.
  • Another suggestion  – from Leviathan Linden – would be to keep the meeting to once a week, but alternate the Linden chairing it (so not always Rider Linden).
• Questions on Introducing Opacity Control for BOM Layers and Mesh with same material applied to two or more faces but in different slots fail in interesting manner met with pretty much the same response: the ongoing back-end work and updates has more-or-less presented any significant updates involving the simulator.
  • Pepper Linden did indicate there is a desire within LL to do ore with Bakes On Mesh (e.g. PBR support).
• llGetRegionWorldMapTile is tracked, but currently not on the roadmap for implementation.
• A discussion on a Canny requesting the ability to trigger animations by UUID: how  / good bad the idea might be; the need to respect content rights (e.g. the The animation asset and the actively playing animation needing separate UUIDs).
  • No conclusions were drawn at the meeting.
• The above got folded into a discussion on increasing regions sizes, based on this idea, and on a further discussion on UUIDs as a means of storing outfits to “save links” in inventory, uses for “wardrobe2 systems such as CTS, etc.
• LSL functions to adjust parcel settings was raised and received positive responses from meeting attendees & Lindens (with a due discission on permissions and preventing idiots maliciously using scripts to bugger with other people’s land.

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a rooftop of people every week. They are taken from my list of region visits, with a link to the post for those interested.

The following notes were taken from the Tuesday, June 10th, 2025 Simulator User Group (SUG) meeting. They form a summary of the items discussed, and are not intended to be a full transcript. The notes were taken from my chat log of the meeting. No video this week.

Meeting Overview

• The Simulator User Group (also referred to by its older name of Server User Group) exists to provide an opportunity for discussion about simulator technology, bugs, and feature ideas.
• These meetings are conducted (as a rule):
  • Every Tuesday at 12:00 noon SLT.
  • In text (no Voice).
  • At this location.
• Meetings are open to anyone with a concern / interest in the above topics, and form one of a series of regular / semi-regular User Group meetings conducted by Linden Lab.
• Dates and times of all current meetings can be found on the Second Life Public Calendar, and descriptions of meetings are defined on the SL wiki.

Simulator Deployments

• There are no planned deployments to any channels this week, only restarts.
• The Preflight RC will likely get a WebRTC update in the week; the simulator version won’t change but the service will be different – the release includes a fix for a file descriptor leak that lead to crashes. This does not require any viewer-side updates.

SL Viewer Updates

• Official Viewer: 2025.04 – 7.1.14.15192634334, issued May 25, promoted May 28 – No Change.
• Second Life Project glTF Mesh Import, version 7.1.14.15361077240 June 2 – No Change.
• Second Life Project Lua Editor Alpha (Aditi only), version 7.1.12.14888088240, May 13 –  No Change.

In Brief

• Parcel boundaries:
  • a long standing issue is that of people (mostly on Mainland) unexpectedly hitting parcels that are closed to public access (e.g. because the parcel edges onto a public road), and the ensuing confusion of getting bounced / losing the vehicle they are on, etc.
  • Rider Linden is hoping to be able to take another look at this in the near future, in terms of making such events less chaotic.

Just to remind people … the parcel bounce is for vehicles entering a parcel. It would check the permissions of all sitters and deny entry if any one sitter couldn’t enter. Essentially it would “bounce” the whole vehicle.

• • The response from those at the meeting was generally positive to this, in that it would end the situation of avatars being unseated from a vehicle which might still be able to enter / pass through the parcel.
• SLua event handling proposal is being worked on – but exactly what this means could not be specified at the meeting.
• A general discussion on mesh, mesh physics, uploads and decomposition, which appeared largely driven by a user seeking clarification, which strayed over into the realm of region crashers.
• The subject of possibly deprecating pathfinding on the simulator (and potentially removing Havok from the viewer, allowing for an alternation for mesh decomposition came up at the meeting: see the In Brief section of my TPVD Meeting Summary for week #23 2025, for more.
  • In addition, Leviathan Linden indicated that pulling “some” Havok dependencies from the viewer could make it easier for physics engine updates.
  • The led to a lengthy discussion on how pathfinding might be replaced, concerns from those who are using it, with no definitive solutions.

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a rooftop of people every week. They are taken from my list of region visits, with a link to the post for those interested.

The following notes were taken from the Tuesday, June 3rd, 2025 Simulator User Group (SUG) meeting. They form a summary of the items discussed, and are not intended to be a full transcript. The notes were taken from my chat log of the meeting. No video this week.

Meeting Overview

• The Simulator User Group (also referred to by its older name of Server User Group) exists to provide an opportunity for discussion about simulator technology, bugs, and feature ideas.
• These meetings are conducted (as a rule):
  • Every Tuesday at 12:00 noon SLT.
  • In text (no Voice).
  • At this location.
• Meetings are open to anyone with a concern / interest in the above topics, and form one of a series of regular / semi-regular User Group meetings conducted by Linden Lab.
• Dates and times of all current meetings can be found on the Second Life Public Calendar, and descriptions of meetings are defined on the SL wiki.

Simulator Deployments

• There are no planned deployments to any channels this week, only restarts.

SL Viewer Updates

• Official Viewer: 2025.04 – 7.1.14.15192634334, issued May 25, promoted May 28 – NEW.
• Second Life Project glTF Mesh Import, version 7.1.14.15361077240 June 2 – NEW.
• Second Life Project Lua Editor Alpha (Aditi only), version 7.1.12.14888088240, May 13 –  No Change.

In Brief

• As noted in the previous update, the WebRTC “switch on” has been on hold, in part due bugs, performance optimisations, and infrastructure updates.
  • A new version of the code is due to be deployed, aimed at addressing some of the first two of these requirements.
  • There is also the issue of around 21% of Firestorm users not running a WebRTC capable version of that viewer, which is also a potential impact on the switch-over.).
  • In the WebRTC prototype the audio mixing/relaying happens on the same host as the region; there is a project to move that compute onto dedicated server stacks.
• Given the on-going issues with the SL wiki (the latest being a sustained DDOS-type impact, thought to be caused by “aggressive and improper crawler bots”), it was indicated that LL are planning to move away from using the mediawiki platform to a new service. No details were given on what service this might be,  and the statement was followed by numerous appeals for all existing SL wiki data to be ported and/or not lost.
• SLua:
  • There is something of a performance bottleneck with SLua in that SLua scripts run so much faster = people want to make content that thrashes prim params quickly = the server struggles to send the updates fast enough, causing the bottleneck.
    • Leviathan Linden had been looking at this and is hoping to get back to it soon, noting that he should be able to offer some gains in the speed with which the server sends the updates.
    • However, he doubts the Lab will “be able to fully unlock the SLua potential for thrashing object properties” without a “major overhaul of the communication protocol”.
  • It has been noted that  some ll.List functions produce SLua run-time errors when working with lists (tables) that contain nil values. This is a known issue at the Lab, and discussion on how to address it are in progress.
• General, user-led discussions on:
  • Bots (e.g. better account verification).
  • The potential to improve / replace Media on a Prim (MOAP) – such as replacing it with SVG rendering on a prim (seen as handy for use in HUDs and well), or reducing the requirement for every object using MOAP to call its own browser instance. LL do not appear to have any work on the roadmap for either of these, although feature requests for SVG support were noted as having been “seen”.

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a rooftop of people every week. They are taken from my list of region visits, with a link to the post for those interested.

The following notes were taken from the Tuesday, May 27th, 2025 Simulator User Group (SUG) meeting. They form a summary of the items discussed, and are not intended to be a full transcript. The notes were taken from my chat log of the meeting. No video this week.

Meeting Overview

• The Simulator User Group (also referred to by its older name of Server User Group) exists to provide an opportunity for discussion about simulator technology, bugs, and feature ideas.
• These meetings are conducted (as a rule):
  • Every Tuesday at 12:00 noon SLT.
  • In text (no Voice).
  • At this location.
• Meetings are open to anyone with a concern / interest in the above topics, and form one of a series of regular / semi-regular User Group meetings conducted by Linden Lab.
• Dates and times of all current meetings can be found on the Second Life Public Calendar, and descriptions of meetings are defined on the SL wiki.

Simulator Deployments

• There are no planned deployments to any channels this week, only restarts.

The team has been working on a lot of backend work getting things rebuilt for a more modern artifact management solution (think: rebuilding docker containers, libraries, etc.) –this is ongoing work. We also are doing more invisible work updating hardware to a newer configuration.

– Signal Linden

SL Viewer Updates

• Default viewer: 2025.03 7.1.13.14343205944, issued April 9th and promoted April 15.
• Release Candidate: 2025.04 – 7.1.14.15192634334, May 25 2025 – Updated.
• Second Life Project Lua Editor Alpha (Aditi only), version 7.1.12.14888088240, May 13 –  No Change.

In Brief

• A useful Feature Request: Log in Screen: “Region Offline” or “Region Restarting” warning prompt – vote!
• A question on whether or not a viewer should expose the channel llDialog is operating on, or whether that is private information. Short answer: no it is not private; it’s in the viewer.
• A debate as to how many regions run on a simulator and how many simulators run on a server, after a claim was made it is not 1:1:1.
  • Leviathan Linden: SL runs one Region per Simulator process. The actual Server (machine) runs multiple Simulators.
  • Monty Linden: the old 1/core vs 4/core is long gone – departed with uplift.
• Confusion was voiced about region crossings and the idea that an avatar’s inventory is “handed over” between regions. This is not the case; only object inventory (scripts in your attachments) is transferred.
  • The confusion may have arisen by conflating issues of inventory size causing issues at log-in (which the Lab has been investigating) with the idea that the same is true for region crossings.
• WebRTC “switch on” is still being held – currently because it still needs some bugs fixed; LL is looking to get the infrastructure sorted for a wider deployment across regions and is also looking at performance optimisations (as well as the issue of around 21% of Firestorm users not running a WebRTC capable version of that viewer).
• A lot of general chit-chat about myths, frame rates, PBR and its impact on older hardware, why the avatar count in the Destination Guide tend not to match the actual count in the region (because people can come and go quickly / time is required for the simulator to forward the information to the relevant service handling the DG and for it to be processed and displayed; updates to the DG are not real-time), and science fiction series (sorry, you had to be there).

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a rooftop of people every week. They are taken from my list of region visits, with a link to the post for those interested.

The following notes were taken from the Tuesday, May 20th, 2025 Simulator User Group (SUG) meeting. They form a summary of the items discussed, and are not intended to be a full transcript. The notes were taken from my chat log of the meeting. Pantera also recorded the meeting, and that recording is embedded at the end of this piece – my thanks to Pantera, as always, for providing it.

Meeting Overview

• The Simulator User Group (also referred to by its older name of Server User Group) exists to provide an opportunity for discussion about simulator technology, bugs, and feature ideas.
• These meetings are conducted (as a rule):
  • Every Tuesday at 12:00 noon SLT.
  • In text (no Voice).
  • At this location.
• Meetings are open to anyone with a concern / interest in the above topics, and form one of a series of regular / semi-regular User Group meetings conducted by Linden Lab.
• Dates and times of all current meetings can be found on the Second Life Public Calendar, and descriptions of meetings are defined on the SL wiki.

Simulator Deployments

• There are no planned deployments to any channels this week, only restarts.

SL Viewer Updates

•  Default viewer: 2025.03 7.1.13.14343205944, issued April 9th and promoted April 15th.
• Release Candidate: 2025.04 – 7.1.14.14911904105, updated May 13th 2025.
• Second Life Project Lua Editor Alpha,7.1.12.14888088240, updated May 13th 2025.
  • Will only work on Aditi. Blog post: Lab officially announces Luau Alpha testing.

SLua Updates

I’m going to write up an implementation of better event handling in pure SLua so that people can get a feel for the API and make suggestions before we commit to actually implementing a specific implementation in the server.

Got sidetracked improving setlinkprimitiveparamsfast perf with many PRIM_LINK_TARGETs since I saw that bogging down the SLua alpha sims but I’m back on track now 🙂

– Harold Linden (SLua development contractor)

• It was reiterated that the plan remains to move SLua to a more open beta on Agni (the Main grid), once further updates have been made by LL. (Such as the event handling and memory management mentioned). When this happens, it will initially be to a “handful of regions” prior to gaining broader deployment.
• Harold Linden indicated that most of the current Canny Feature Requests for SLua will be implemented during the beta phase of the project – although some, such as “require” will take time to “do properly”, and so there may be stopgap solutions “similar to the ones people already use for LSL that uses local pre-processing.”

Not ideal but there’s a lot of yak shaving that needs to be done to get proper “require” working with new “library” type assets and don’t want to block the rest of SLua on it. 

• In responding to a comment about an possible inter-script dependency system, he further noted:

There would be no inter-script dependencies per-se, this is more akin to pure modules that can just export types and functions etc with no shared state. More like a statically linked library that only gets evaluated when the script is compiled. It’s essentially just enabling something that people already tend to do with pre-processors, the only difference is the assets live with the rest of your stuff.

• This sparked a debate on the use of libraries, plug-ins ,etc., a lot of which is “still TBD”, other with matters of object update handing, etc. This discussion ran through must of the remaining 40 minutes of the meeting. Please refer to the video for specifics (as I am not a coder, and far from qualified to interpret all of the discussion!).
• One important additional point was raised by Harold Linden:

Oh right, I feel like I should mention, we’re trying to track down a couple potential memory corruption bugs in SLua that we’ve had trouble reproducing on our dev machines. We’re going to look at pushing a version of the server with debugging instrumentation (AddressSanitizer) to the SLua sims on beta grid. It might make things slightly slower, but it’s only temporary.

In Brief

“Missing Content on Login”

We had a repro recipe for “missing content on login” and I was able to kinda fix it. It was semi-reliable (would happen maybe 20% of the time) for one our viewer dev contractors, but I couldn’t reproduce it myself. It is “kinda” fixed in that I have eliminated some unnecessary resets during login that would help trigger the bug, with a subsequent savings of effort and bandwidth of object update data on arrival. However the root race condition that is being avoided… I didn’t actually figure that out. 

So… I would expect improvements (reduction of missing content on login) but I don’t think this fixed everything. In particular, I thought maybe it would help reduce the rate of missing attachment items on avatars, but upon more thought I realized this fix is not relevant to that problem. Anyway, heads up: this fix is expected to be in Fig Pudding [the next simulator update].

– Leviathan Linden

TP Failure and Log-in Issues

• Reports suggest that that has been a “big increase” in TP failures and login failures over the last week (I can attest to the former; having had around a 40% TP failure rate on first attempts to get somewhere on several days). Viewer logs and times incidents occurred, submitted via Canny, would be helpful in debugging issues.
• It was also noted that LL is engaged in making some network infrastructure changes, so again, a request was made for those “experiencing connectivity problems not of the usual sort or frequency” to file a Canny report would be useful. Times, places, names, and log files.
• The game_control capability remains on-hold. Leviathan Linden is currently engaged in other work, and unfortunately, game_control is is “near the bottom of” the stack of work he has on-hold as a result.

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a rooftop of people every week. They are taken from my list of region visits, with a link to the post for those interested.

The following notes were taken from the Tuesday, May 13th, 2025 Simulator User Group (SUG) meeting. They form a summary of the items discussed, and are not intended to be a full transcript, and were taken from my chat log of the meeting. Pantera also recorded the meeting, and that recording is embedded at the end of this piece – my thanks to Pantera, as always, for providing it.

Meeting Overview

• The Simulator User Group (also referred to by its older name of Server User Group) exists to provide an opportunity for discussion about simulator technology, bugs, and feature ideas.
• These meetings are conducted (as a rule):
  • Every Tuesday at 12:00 noon SLT.
  • In text (no Voice).
  • At this location.
• Meetings are open to anyone with a concern / interest in the above topics, and form one of a series of regular / semi-regular User Group meetings conducted by Linden Lab.
• Dates and times of all current meetings can be found on the Second Life Public Calendar, and descriptions of meetings are defined on the SL wiki.

Simulator Deployments

• On Tuesday, May 13th, the Main SLS channel was updated with the Elderberry simulator release.
• Om Wednesday, May 14th, the RC channels should be restarted without update.

Upcoming Deployment – Fig Newton (2025.06)

• Yes, the name changed in the passage of a week.
• This is still being put together, and is unlikely to surface before June, as the simulator team has been focusing on some necessary internal work which has drawn attention away from feature work on the simulators.

SL Viewer Updates

•  Default viewer: 2025.03 7.1.13.14343205944, issued April 9th and promoted April 15th.
• Release Candidate: 2025.04 – 7.1.14.14911904105, updated May 13th 2025.
• Second Life Project Lua Editor Alpha,7.1.12.14888088240, updated May 13th 2025.
  • Will only work on Aditi. Blog post: Lab officially announces Luau Alpha testing.

In Brief

• Rider Linden requested if people preferred code-names for simulator updates or their official initial version numbers (e.g. 2025.05, 2025.06).
  • Given that version umbers actually relate to minor things like RELEASE NOTES – they actually serve a use.
  • As noted by Fig Pudding Newtons, code names can change on a whim and seem pretty pointless.
  • However, it appears an attempt to use both will be used going forward 🙄(yes, I’m a carbon-based unit and I have no sense of fun‡).
• PBR Colour data is lost when setting PBR overrides was raised some time ago, but has yet to be fixed. Responding to a question on why it had not been fixed when implementing llSetLinkGLTFOverrides, Rider Linden stated:

Because when PBR was implemented they did not separate the colour value from the alpha. The two are stored internally as a single number. Since the simulator does not have the actual value from the material (it does not read materials) there is no way to change one without impacting the other. Doing so would have required a protocol change in the way overrides are sent and protocol changes are big deals since they break the viewer.

• • He went on to note that overrides are among a number of things he would like to revamp and improve upon.
• The above led to a request for creators refreshing older products with PBR to be able to supplement llSetLinkAlpha to some sort of llSetLinkPBRAlpha, without having to “dual stack” materials.
  • Rider Linden indicated that this would require adding a new function, and as such perhaps best done when overrides are being revamped, per the above comment.
  • Leviathan Linden further noted that Geenz Linden is currently thinking about how to overhaul GLTF override system, as fallout of planning on how to support object hierarchy.
• A portion of the chat was around When an object is paid the object name being recorded should be controlled by the Server and not the Viewer, seen as a particular concern among providers of Skill Games. This topic was also raised extensively at the Skill Gaming meeting.
• Most of the meeting revolved around Blinn-Phong, glTF, alpha and colour overrides, most of which I, frankly, am not qualified to talk about in a meaningful way. Please refer to the video.
• The latter half of the meeting involved the potential for physical region crossings between regions that are non-contiguous (e.g. your are on “Region A” and can “see” and “cross into” (walking, via vehicle) “Region B” directly (no actual manual teleport trigger), even though “Region B” is on the 2other side” of the grid. See: “Wormhole Regions” (Non-Cartesian region crossing).
  • This is something that has apparently been raised a lot within LL and seen and a “neat idea” and potentially possible. But it would be “way down on a list, below all sorts of important stuff to fix.”
• Leviathan Linden is still trying to work out the “sometimes objects don’t show up on login” problem. He now has a reliable repro for this issue and is using it to try to understand why and where things are going wrong.
• Off-lines not appearing on log in until relogging his become an increasing issue of late.  Commenting on the report, Leviathan Linden stated:

The fact that the off-lines show up in a second session suggests that they were never successfully requested by the viewer in the earlier session, since otherwise they would have been cleared (considered delivered) at the server. So we’re wondering: why isn’t the viewer correctly invoking some cap? 

† The header images included in these summaries are not intended to represent anything discussed at the meetings; they are simply here to avoid a repeated image of a rooftop of people every week. They are taken from my list of region visits, with a link to the post for those interested.

‡That’s a Hitch Hiker’s Guide Reference, in case you read this far.