Tux Machines

This Week in GNOME and Christian Hergert on Sysprof

Posted by Roy Schestowitz on Aug 05, 2023,

updated Aug 05, 2023

This Week in GNOME/Felix Häcker: #107 Reduced Overheads

Update on what happened across the GNOME project in the week from July 28 to August 04.

Christian Hergert: More Sysprof’ing

Last time I wrote we talked about a new search index for libgweather. In the end I decided to take another route so that we can improve application performance without any changes. Instead, I added a kdtree to do nearest neighbor search when deserializing GWeatherLocation. That code path was looking for the nearest city from a latitude/longitude in degrees.

The merge request indexes some 10,000 lat/lon points in radians at startup into a kd-tree. When deserializing it can find nearest city without the need for a linear scan. Maybe this is enough to allow significantly more data into the database someday so my small hometown can be represented.