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This is on kernel 6.12 (Debian Stable) on both host and guest, system load is moderate, the host CPUs are not pegged at 100% at any time. The guest has only one virtual CPU core assigned. > > [11622.031047] hrtimer: interrupt took 12354614 ns > [46723.139964] hrtimer: interrupt took 8522695 ns > /* * The next timer was already expired due to: * - tracing * - long lasting callbacks * - being scheduled away when running in a VM This message used to come if the timer expiry was in past and it was tried 3 times and still can't catch up. Very likely it was due to guest being scheduled away. This behavior has changed now and this particular trace has been removed. https://lore.kernel.org/all/20260224163430.870639266@kernel.org/ > This *may* be related to the dropped / late interrupts I have reported in earlier messages, but it could also be a separate issue. QEMU version is 7.2.22.