I have a quad-core x86_64 Gentoo system with a GeForce GT 730 card, PCI ID 0f02, which must use the legacy 390.xx driver. The latest version from portage, 390.87, 1/16/19, appears to cause excessive IRQs. The symptom is that every three minutes, htop reports that CPU0 is at 100% for about ten seconds and the GUI freezes for that time period. htop also reports that the kernel thread ksoftirqd/0 is responsible for this. Right now TIME+ in htop reports 4:42.69 for ksoftirqd/0, 0:00.87 for ksoftirqd/2, 0:28.03 for ksoftirqd/3, and 0:00.74 for ksoftirqd/1. (I’m not using the threadirqs boot option.)
Is this likely to be hardware (video card) failure or a bug in the 390.87 driver from portage?