The following notes are drawn from the TPV Developer meeting held on Friday October 10th, and shown in the video above. Time stamps, where relevant, have been included for ease of reference to the video. Note that items are listed according to subject matter, rather than chronologically, so time stamps may appear out-of-sequence in places. My thanks as always to North for the recording.
HTTP Pipeline Viewer
[0:26:35] As noted in part 2 of this week’s report, the HTTP pipelining viewer was looking close to being ready for deployment as an RC viewer, possibly in the next week. However, it hit a final QA snag, and in Oz’s words, “Monty is busily correcting the problem and getting it back in the queue.” Or as Monty put it in chat “:(“. Apparently a workaround for a CURL bug “tends to disable pipelining”.
Benchmark and Experience Tools Viewers
[0:27:20] It is hoped that these two project viewers will be updating and moving into the viewer release channel as release candidates “pretty soon”.
Viewer Build Tool Chain
[0:41:51] The tools upgrade project for building the viewer has been subject to a few delays. Currently, the Lab has just about finished putting together all the build prerequisites for building the Mac version of the viewer directly on OS X 10.9, and are about to commence test builds of the viewer using the new tool chain. This has also led to some progress being made on updating the Linux build process as well. The windows environment will require further work, so it will be a little longer before things are fully in place.
[0:28:58] Again, as noted in part 2 of this week’s report, the latest updates for group chat are being deployed to various back-end chat servers by the Lab, and may be deployed to all of the chat servers in the next week.
While investigating group chat, the Lab has noticed that in general it is “unbelievably spikey”, with chat sessions having peaks of really good performance followed by troughs of really bad performance regardless as to whether the groups are regarded as being “good” or “bad” in handling group chat. There is no real pattern to these peaks and troughs, other than the larger the group, the more it seems to swing between the two extremes, and nothing to correlate them with anything in particular beyond the bad times occurring when a lot of people in a group are online.
Z-offet height Adjustment
[0:31:52] Work is continuing on the z-offset height proposal, which Vir Linden has been engaged upon. However, it appears the Lab has encountered some issues which have made it “a little more complicated” than had initially be thought. hopefully, these will be overcome, and they won’t bring the work to a halt.
[0:32:28] As noted in part 2 of this week’s report the number of regions on Snack and utilising the Highwinds CDN for mesh and texture data servicing had reached around the 270 mark, but has since come down a little as a result of the Lab overloading the Snack sim hosts with regions running high volumes of users.
Metrics gathered by the Lab have been positive, and even though the Snack sim hosts were initially overloaded, the Lab feel they performed significantly better thanks to texture and mesh fetching being off-loaded to the CDN than would have been the case had the “old” method of texture / mesh fetching still been in use.
One aspect of the move to using the CDN is that until now, the sim host Apache service was being used for texture and mesh data handling and “lots” of other things which are timing critical to operations such as region crossings. With the move to the CDN, much (if not all) of the texture and mesh data handling is removed from the Apache service, making it easier for it to better handle time-critical activities.
If all goes according to plan, the CDN support will be expanded to the BlueSteel release candidate channel in week 42 (commencing Monday October 13th). This will allow the Lab to gain data on performance using the CDN support which can be directly compared with historical data available for region / sim host performance in BlueSteel. Those regions already running on Snack will continue to do so alongside of BlueSteel, so that around 5% of the main grid will be using the CDN service.
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