[Rossoreed]

Just tried to install Kodi on a Raspberry Pi 3 running the currently released raspberry software version - Raspbian Stretch and it is hardly usable.

Installed by;
$ sudo apt-get update
$ sudo apt-get install kodi

It takes a long time to load, and navigation is extremely slow, lagging by about 5 seconds.

Is this a known issue?

[rascas]

Yes, search the forum and you will have your answer and how to fix it, which is basically updating your system...
If after that you still have problems, post your Kodi log.

[Rossoreed]

Strange, the OS was a clean install tonight, followed by update/upgrade, before installing Kodi.
The first installation gave me v17.1
I removed it and tried to install it a second time - this time I got v17.4 which runs fine.

[rascas]

The problem is, like already explained multiple times, at the time of the Raspbian Stretch image release by the Raspberry Pi Foundation, the only version of Kodi available in the repos, was the Debian generic version, which is compiled against OpenGL, so not optimized for the Raspberry Pi. That was Kodi 17.1 that you probably installed. Some days after, there was available a new Kodi version, 17.4, which is optimized for the Raspberry Pi.
So if you just installed a fresh copy of Raspbian Stretch, you need to update/refresh packages before installing Kodi, otherwise you will get the said generic Kodi version.
Updating before installing Kodi in Stretch, is confirmed to be working, multiple times.