
fetch -o - https://raw.githubusercontent.com/toreamun/opnsense-plugins/main/install.sh | shQuote from: meyergru on July 06, 2026, 09:14:34 PMI mean that it is probably the CPU waiting for I/O operations to finish because the storage subsystem is struggling. With NVMe storage, writing very small, frequent log lines leads to heavy 'write amplification' due to the large underlying flash block sizes, causing significant latency spikes.
The fact that reducing the logging activity resolved the issue completely confirms the storage bottleneck theory. When the logging was set to high, the frequent, small writes to the NVMe caused massive write amplification and continuous synchronous I/O blocks.
In FreeBSD/OPNsense, such a severe storage backlog causes 'Lock Contention' in the kernel and forces an influx of Software Interrupts (SWIs) to manage the blocked I/O buffers. This is why the IRQ handler threads (intr) ran hot: they weren't just processing network packets, but handling the massive overhead of a stalling filesystem trying to commit log rows to a struggling SSD. Turning down the logs broke this vicious cycle.