CPU hog in vnlru and arc_prune on 13-STABLE

Hi,

I have a fresh (git b9880e247b26) 13.3-STABLE running in bhyve with 2 vCPU and 10G of RAM.

I’ve put some load on it (building lang/rust from ports outside poudriere, using make -j2) and the system
started to respond very slowly.

I did break the make process and I was able to look into top where there was:

  PID USERNAME    PRI NICE   SIZE    RES STATE    C   TIME    WCPU COMMAND
    0 root         -8    -     0B  1808K CPU1     1  35:53  99.79% kernel{arc_prune}
   15 root         20    -     0B    16K RUN      0  34:19  99.35% vnlru

The high CPU usage remains even after 30 minutes after the make was stopped.

How can I narrow down the root cause? For the record, the kernel is GENERIC.

Thanks
otis

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Juraj Lutter
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