Re: TerraSync / CDN hosting

What is the status of this?

--
Josh Davidson
________________________________
From: Fabiano Notari <[email protected]>
Sent: Sunday, June 28, 2026 08:31
To: FlightGear developers discussions <[email protected]>
Subject: Re: [Flightgear-devel] TerraSync / CDN hosting

https://forum.flightgear.org/viewtopic.php?f=25&t=44466#p440306

I found this suggestion on the forum for an alternative Terrasync link:
--prop:/sim/terrasync/http-server=https://terrasync.eti.pg.gda.pl/ts
I tried it and it works!

Kind regards,
Fabiano

Il giorno mar 30 set 2025 alle ore 13:30 James Turner <[email protected]<mailto:[email protected]>> ha scritto:
Some update info on TerraSync: for six weeks now I’ve been using a real CDN as *one* of the TerraSync mirrors, and since three weeks ago, it’s the ‘entire’ mirror. This is all controlled by Curt+TorstenD via the DNS settings (NAPTR records), we can switch it around at will.

The important data-point I’ve already got is that with current contributions to OpenCollective, we can easily afford the bandwidth - providing the usage remains the same, or grows proportionally to contributions. The CDN has hosts globally, so this should improve the experience for people in ‘everywhere apart from North America and Europe’.

There’s a bunch more interesting data points, which will likely prompt some code tweaks in upcoming releases:

- we need to implement HTTP cache-validity checks on the most commonly checked files. There was also a stupid bug in this area, I’ve implemented both cache-checking and fixed the bug on `next` and will back-port these fixes to stable, probably for 2024.1.4

<https://gitlab.com/flightgear/simgear/-/issues/27>
[FlightGear_logo.png]
Add If-Modified-Since / ETag caching to TerraSync (#27) · Issues · FlightGear Flight Simulator / simgear · GitLab<https://gitlab.com/flightgear/simgear/-/issues/27>
gitlab.com<https://gitlab.com/flightgear/simgear/-/issues/27>

https://gitlab.com/flightgear/simgear/-/issues/28

(These will save a lot of *requests* to the servers, but not actually reduce the amount of bytes transferred much)

- adding real archive support so we can use zipped data for each 1x1 would be beneficial, the current file structure is very unfriendly for web caches (and FG itself). (The epic for this is https://gitlab.com/groups/flightgear/-/epics/7 )

- Providing FGData downloads via the CDN is currently *not* financially viable, so we’re better using the unlimited bandwidth mirrors for that. That does include Ibilbio and SourceForge, as well as ‘our’ mirrors.

To give it some perspective TerraSync is so far is 3TB in September, FGData downloads from fresh installs hit the 10TB cap I set, on the 12th of September. Each install via the CDN costs us $0.01 (1 cent) since FGdata is ~ 2Gb and the volume pricing tier on our CDN is $0.005/GB : so 10TB is 5000 installs, in principle. (Also if we get featured on some news site etc, we don’t want to suddenly be paying more: hence why I set the caps)

The ‘good’ news is that if we don’t use the CDN for the base package, we can now safely grow it (eg to 3GB or more) *without* impacting anything. This means we can consider some quality-of-life improvements like including the TerraSync shared models in the base package directly, and also the Airports data. This would give a much cleaner out-of-the-box experience, since users won’t need to wait on transferring those rather heavy dirs entirely before they can make their first flight. ( https://gitlab.com/flightgear/flightgear/-/issues/3231 )

Kind regards,
James
_______________________________________________
Flightgear-devel mailing list
[email protected]<mailto:[email protected]>
https://lists.sourceforge.net/lists/listinfo/flightgear-devel

_______________________________________________
Flightgear-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/flightgear-devel