MP批插优化

@RestController
public class SegmentController {
    private final Map<String, AtomicLong> segmentPool = 
        new ConcurrentHashMap<>();

    @PostMapping("/segment/apply")
    public SegmentResponse applySegment(
        @RequestParam String bizTag, 
        @RequestParam int step) {

        long currentMax = segmentPool.compute(bizTag, (k, v) -> 
            v == null ? new AtomicLong(0) : v
        ).addAndGet(step);

        return new SegmentResponse(
            currentMax - step + 1, 
            currentMax
        );
    }
}

public class SegmentBuffer implements InitializingBean {
    private volatile Segment currentSegment;
    private volatile Segment nextSegment;
    private final ExecutorService loader = 
        Executors.newSingleThreadExecutor();

    public synchronized Long nextId() {
        if (currentSegment.getCurrent() > currentSegment.getMax()) {
            if (nextSegment == null || nextSegment.getCurrent() > nextSegment.getMax()) {
                loadSegments();
            }
            currentSegment = nextSegment;
        }
        return currentSegment.incrementAndGet();
    }

    private void loadSegments() {
        loader.submit(() -> {
            nextSegment = fetchNewSegment();
        });
    }

    // 省略容错机制
}

public class HybridIdGenerator implements IdentifierGenerator {
    private final SegmentBuffer buffer;

    @Override
    public Number nextId(Object entity) {
        return buffer.nextId();
    }
}

// 动态步长算法示例
public int calculateStep(int currentQPS) {
 int baseStep = 1000;
 double factor = Math.log10(currentQPS / 1000.0);
 return (int) (baseStep * Math.pow(2, factor));
}

原始长整型：135790246813579 (15位)
Base62编码：2Cst5WJ (7位)