TIMESTAMP_QUERY_INSIDE_PASSES feature must be enabled to cal

Error message

TIMESTAMP_QUERY_INSIDE_PASSES feature must be enabled to call write_timestamp in a compute pass.

What it means

On the WebGPU backend, ComputePassEncoder::write_timestamp is not supported, so wgpu panics. The message indicates the TIMESTAMP_QUERY_INSIDE_PASSES feature would be required, and that capability cannot be satisfied via the WebGPU backend path.

Source

Thrown at wgpu/src/backend/webgpu.rs:3666

    fn set_immediates(&mut self, _offset: u32, _data: &[u8]) {
        panic!("IMMEDIATES feature must be enabled to call set_immediates")
    }

    fn insert_debug_marker(&mut self, label: &str) {
        self.inner.insert_debug_marker(label);
    }

    fn push_debug_group(&mut self, group_label: &str) {
        self.inner.push_debug_group(group_label);
    }

    fn pop_debug_group(&mut self) {
        self.inner.pop_debug_group();
    }

    fn write_timestamp(&mut self, _query_set: &dispatch::DispatchQuerySet, _query_index: u32) {
        panic!("TIMESTAMP_QUERY_INSIDE_PASSES feature must be enabled to call write_timestamp in a compute pass.")
    }

    fn begin_pipeline_statistics_query(
        &mut self,
        _query_set: &dispatch::DispatchQuerySet,
        _query_index: u32,
    ) {
        // Not available in gecko yet
    }

    fn end_pipeline_statistics_query(&mut self) {
        // Not available in gecko yet
    }

    fn dispatch_workgroups(&mut self, x: u32, y: u32, z: u32) {
        self.inner
            .dispatch_workgroups_with_workgroup_count_y_and_workgroup_count_z(x, y, z);
    }

View on GitHub (pinned to 3e11ff59bf)

Solutions

Gate pass-level write_timestamp on Features::TIMESTAMP_QUERY_INSIDE_PASSES (from adapter.features()) AND a non-WebGPU backend.
Skip timestamp instrumentation on web and use CPU timers.
Configure profiling instrumentation once at device creation via a capability flag.
Read/resolve timestamps only on backends where they were recorded.

Example fix

// before
compute_pass.write_timestamp(&timestamps, 0);
// after
if timestamps_enabled && !is_webgpu {
    compute_pass.write_timestamp(&timestamps, 0);
}

Defensive patterns

Strategy: validation

Validate before calling

if device.features().contains(Features::TIMESTAMP_QUERY_INSIDE_PASSES) && !is_webgpu_backend {
    compute_pass.write_timestamp(&qs, 0);
}

Type guard

fn supports_pass_timestamps(f: Features, b: Backend) -> bool {
    f.contains(Features::TIMESTAMP_QUERY_INSIDE_PASSES) && b != Backend::Browser
}

Prevention

Feature-gate pass timestamp instrumentation at profiler construction time.
Keep the profiling abstraction configurable per backend.
Skip GPU timestamps on browser targets and use performance.now().
Audit all write_timestamp call sites after backend changes.

When it happens

Trigger: Calling compute_pass.write_timestamp(query_set, query_index) on a compute pass running via the webgpu backend.

Common situations: GPU profiling code instrumenting compute passes, compiled to wasm; backend-agnostic profiler traits calling write_timestamp unconditionally; assuming native support carries over to the browser.

Related errors

AI-assisted analysis of gfx-rs/wgpu@3e11ff59bf (2026-09-03). Data as JSON: /api/errors/67c69f9a4d5576f0. Report an issue: GitHub.