<!-- TITLE: ERR-SYS-00007: Performance Issues with Fontconfig <= 2.12.92 --> <!-- SUBTITLE: Fc-Cache Algorithm Issues, Long Font Installation Times, and Unresponsive Desktop --> # Summary With Fontconfig version < 2.12.92, an inefficient algorithm has been utilised with its Fontconfig cache generator (`fc-cache`), useful for caching font information, and speeding up font display in graphical applications. However, with larger collections of fonts installed - especially with larger CJK (Chinese, Japanese, and Korean) fonts like `noto-cjk-fonts` - the utility may require several minutes, or more to complete on slower devices (ARM boards, and older PowerPC-based Macintoshes), during which... - Graphical applications may not launch, or takes minutes to show its interface. - GNOME Shell in particular may lock up and require a system reboot, which may interrupt system updates or package installation, rendering the system unusable until these operations are manually resumed. # Possible Cause It is difficult to digest the causation and the upstream solution to this issue. This is best described from the original upstream bug report, where a faster `fc-cache` implementation was worked on and merged at the end, [ref](https://bugs.freedesktop.org/show_bug.cgi?id=64766). # Fixed Version Updating to Fontconfig version > 2.12.6 resolves this issue.