OutOfMemoryError: Java heap space内存溢出加内存无用

上传到 其他云厂商的 接口 报错了

300M的没问题，3GB的就不行了

2021-11-04 18:44:45.089  WARN 8724 --- [nio-8081-exec-4] .m.m.a.ExceptionHandlerExceptionResolver : Resolved [org.springframework.web.util.NestedServletException: Handler dispatch failed; nested exception is java.lang.OutOfMemoryError: Java heap space]

代码也是切片上传的

    public static byte[] readFile3(File file){
        InputStream is = null;
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        byte[] b = new byte[1024];
        int n;
        try {
            is = new FileInputStream(file);// pathStr 文件路径
            while ((n = is.read(b)) != -1) {
                out.write(b, 0, n);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }finally{
            if (is != null) {
                try {
                    is.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return out.toByteArray();
    }

                    try {
                        System.out.println("到333");
                        byte[] bytes = readFile3(f);
                        System.out.println("到444");
                        B2UploadFileRequest request = B2UploadFileRequest.builder(bucket, B2Utils.generateFolderPath(patharr) + f.getName(), "", B2ByteArrayContentSource.build(bytes)).build();
                        System.out.println("到555");
                        client.uploadSmallFile(request);
                    } catch (B2Exception e) {
                        e.printStackTrace();
                    }

idea 里面也设置了 启动参数 -Xmx2907m -Xms2907m -XX:NewRatio=4

这是哪里出了问题