uts ios 插件 内存泄漏问题

我在开发ios的uts插件，发现uts环境下，ios的内存回收机制不起作用，只是一个简单下载文件，申请内存Data类，即便已经离开闭包，内存也没有释放，最终由于内存不足，导致闪退。代码如下：
desPackage(decode : string) {
//var decodedData : NSData = new NSData(base64Encoded = decode, options = NSData.Base64DecodingOptions.init(rawValue = 0)) as NSData;
var data : Data = new Data(base64Encoded = decode) as Data;
if (data[0] != 1) {
console.log("error package");
return;
}
var pos = Number.from(data[1]) 256 256 256 + Number.from(data[2]) 256 256 + Number.from(data[3]) 256 + Number.from(data[4]);
var dticket : [UInt8] = [];
for (var i : Int = 0; i < 20; i++) dticket.append(data[5 + i]);
var ticket = this.sha1str(dticket);
if (!this.recvFile.has(ticket)) return;
var recvinfo = this.recvFile.get(ticket) as UTSJSONObject;
var filename = recvinfo.getString("file");
if (filename == null) return;
var rds = this.rds.get(filename!);
if (rds == null) return;
var b : [UInt8] = [0];
/var buf = new Data();
for (var i : Int = 25; i < data.count; i++) {
b[0] = data[i];
buf.append(contentsOf = b);
}
this.writeFile(rds!, buf, pos);/
var sip = recvinfo.getString("sip");
var sport = recvinfo.getNumber("sport");
var packsize = recvinfo.getNumber("packageSize");
if (sip == null || sport == null) return;
if (packsize == null) return;
var spos = Math.floor(pos / packsize!);
var cc = this.confirm.get(ticket);
cc?.delete(spos);
var rcount = recvinfo["rcount"] as number;
rcount = rcount + 1;
if (rcount >= 25 || cc!.size < 25) {
recvinfo.set("rcount", 0);
var ret = "{\"op\":9,\"ticket\":\"" + ticket + "\",\"rcount\":" + rcount.toString() + "}";
var sdata = ret.data(using = String.Encoding.utf8)!;
this.sendByte(sdata, sip!, sport!);
}
else {
recvinfo.set("rcount", rcount);
return;
}
recvinfo.set("time", Date.now());
}
这段代码申请了三个Data对象，最终内存都没有释放，请问是怎么回事，该如何应对！谢谢