Method learn_layout

server/src/server/disk_prefix_cache.cpp:250–281

}

void DiskPrefixCache::learn_layout(int slot) {
    if (disabled()) return;
    if (layout_known_ && !layout_from_disk_) return;  // already verified from live model

    auto ref = backend_.snapshot_ref(slot);
    if (!ref.ctx) return;

    std::array<uint8_t, 16> prev_id = layout_id_;
    bool had_disk_layout = layout_from_disk_;

    compute_layout_id(ref.ctx);

    if (had_disk_layout && std::memcmp(prev_id.data(), layout_id_.data(), 16) != 0) {
        // Model layout differs from what was learned from disk files.
        std::fprintf(stderr, "[disk-cache] layout mismatch: disk=%s model=%s — switching\n",
                     hex(prev_id.data(), 16).c_str(),
                     hex(layout_id_.data(), 16).c_str());
        entries_.clear();
        total_bytes_ = 0;
    }

    layout_known_ = true;
    layout_from_disk_ = false;
    layout_dir_ = config_.cache_dir + "/" + hex(layout_id_.data(), 16);
    mkdir_p(layout_dir_);

    std::fprintf(stderr, "[disk-cache] layout learned: %s\n",
                 hex(layout_id_.data(), 16).c_str());

    // Scan for previously saved files matching this layout.
    scan_directory();
}

// ─── Directory scanning ─────────────────────────────────────────────────