scx_lavd: system completely bogs down when running GStreamer testsuite

[kostadinsh]

Hi, I noticed that whenever I run the GStreamer testsuite while using scx_lavd, my system completely bogs down - audio, video, and the tests running freeze until they eventually finish.

CPU used: Ryzen 7 7800X3D
Kernel version: 7.0.1
Bisect led to: a8a25fc

Steps to reproduce:

1. wget https://gstreamer.freedesktop.org/src/gstreamer/gstreamer-1.29.1.tar.xz
2. tar xpvf gstreamer-1.29.1.tar.xz
3. cd gstreamer-1.29.1
4. meson setup build
5. meson compile -C build
6. meson test -C build

2026-04-23T16:01:33.508443Z  INFO ThreadId(01) scx_lavd: scheds/rust/scx_lavd/src/main.rs:301: Autopilot mode is enabled.
2026-04-23T16:01:33.508544Z  INFO ThreadId(01) scx_lavd: scheds/rust/scx_lavd/src/main.rs:341: Energy model won't be used for CPU preference order.
2026-04-23T16:01:33.508548Z  INFO ThreadId(01) scx_lavd: scheds/rust/scx_lavd/src/main.rs:354: Pinned task slice mode is enabled (5000 us). Pinned tasks will use per-CPU DSQs.
2026-04-23T16:01:33.508553Z  INFO ThreadId(01) scx_lavd: scheds/rust/scx_lavd/src/main.rs:977: Opts {
    verbose: 0,
    autopilot: true,
    autopower: false,
    performance: false,
    powersave: false,
    balanced: false,
    slice_max_us: 5000,
    slice_min_us: 500,
    mig_delta_pct: 0,
    pinned_slice_us: Some(
        5000,
    ),
    preempt_shift: 6,
    cpu_pref_order: "",
    no_use_em: true,
    no_futex_boost: false,
    no_preemption: false,
    no_wake_sync: false,
    no_slice_boost: false,
    per_cpu_dsq: false,
    enable_cpu_bw: false,
    no_core_compaction: false,
    no_freq_scaling: false,
    stats: None,
    monitor: None,
    monitor_sched_samples: None,
    log_level: "info",
    version: false,
    run_id: None,
    help_stats: false,
    libbpf: LibbpfOpts {
        relaxed_maps: None,
        pin_root_path: None,
        kconfig: None,
        btf_custom_path: None,
        bpf_token_path: None,
    },
    topology: None,
}
2026-04-23T16:01:33.561544Z  INFO ThreadId(01) scx_lavd: scheds/rust/scx_lavd/src/main.rs:541: capacity bound:  1024 (6.7015705%)
  primary CPUs:  [0]
  overflow CPUs: [8, 5, 13, 1, 9, 4, 12, 2, 10, 6, 14, 3, 11, 7, 15]
2026-04-23T16:01:33.561551Z  INFO ThreadId(01) scx_lavd: scheds/rust/scx_lavd/src/main.rs:541: capacity bound:  15280 (100%)
  primary CPUs:  [0]
  overflow CPUs: [5, 1, 4, 2, 6, 3, 7, 8, 13, 9, 12, 10, 14, 11, 15]
2026-04-23T16:01:34.147584Z  WARN ThreadId(01) scx_utils::libbpf_logger: rust/scx_utils/src/libbpf_logger.rs:12: libbpf: map 'lavd_ops': BPF map skeleton link is uninitialized

2026-04-23T16:01:34.169767Z  INFO ThreadId(01) scx_lavd: scheds/rust/scx_lavd/src/main.rs:1010: scx_lavd scheduler is initialized (build ID: 1.0.20-ga8a25fcb-dirty x86_64-unknown-linux-gnu)
2026-04-23T16:01:34.169776Z  INFO ThreadId(01) scx_lavd: scheds/rust/scx_lavd/src/main.rs:1014: scx_lavd scheduler starts running.