Systems with an up-to-date version of fontconfig will experience a delay the first time each user logs on to the system¹. This is because the cache format has changed, so the fontconfig bundled in ThinLinc cannot use the system cache files and has to generate its own. The delay depends on how many fonts the system has. It's been between a few seconds to upwards a minute. See bug 7169 and bug 7170. If we upgrade our fontconfig, we could speed up startup on these systems, but it would move the problem to older systems instead. The change seems to be in fontconfig 2.14 and newer. We are on fontconfig 2.13. Known older systems: Fedora 36 RHEL 8 Ubuntu 22.04 Known never systems: Fedora 37 RHEL 9 Ubuntu 23.04 ¹ Or starts the client on a Linux machine
To make things worse, the development version of fontconfig has bumped the number again. Likely going live in fontconfig 2.15. Even more odd, we see that unreleased version 9 for almost all users on our RHEL 8 system. No idea at this point where those cache files are coming from.
Version 9 is now stable in fontconfig 2.15.0 and later. An upgrade now means that the following systems will be slower: * RHEL 8 and older * Fedora 36 and older * Ubuntu 22.04 and older * Debian 11 and older And the following systems will be faster: * RHEL 10 * Fedora 40 and newer * Ubuntu 24.04 * Debian 13 (not released yet) Versions in between these will be neither faster nor slower. Seems like we gain more than we lose, so an upgrade to the latest version seems like a good choice. It would be nice if RHEL 9 had been included, but we've seen most of the issues on Ubuntu, so 24.04 is more important.
Doing this now because we need a new fontconfig for bug 8584.
Could not really see any noticeable delay on Ubuntu 24.04. But I can see that I get a bunch of .cache-7 files in ~/.cache/fontconfig with ThinLinc 4.18.0. After upgrading fontconfig, no such files appearh.
