ValueError：使用节俭时，filedescriptor超出了select（）的范围？

Question

我想通过提供一个远程服务器thrift，下面是我的服务器端试用版：

from test_thrift.test_server.TestService import Iface,Processor
from thrift.Thrift import TType,TException
from thrift.Thrift import TProcessor
from thrift.transport import TSocket
from thrift.protocol import TBinaryProtocol
from thrift.server import TNonblockingServer


port = int(config["server"]["port"])
handler = SmbService()
processor = Processor(handler)
socket = TSocket.TServerSocket(port=port)
server = TNonblockingServer.TNonblockingServer(processor, socket)

server.setNumThreads(100)
server.serve()

在客户端，对于每个请求，我都会创建一个新的连接，并在服务器响应后关闭它。

from thrift.transport.TSocket import TTransportException
from thrift.Thrift import TException
from thrift.protocol import TBinaryProtocol, TCompactProtocol
from thrift.transport import TTransport
from thrift.transport import TSocket
from thrift import Thrift
from test_thrift.test_server import TestService


class SmbClient(object):
    def __init__(self):
        try:
            self.tsocket = TSocket.TSocket(settings.THRIFT_HOST, settings.THRIFT_PORT_PRODUCT)
            self.transportFactory = TTransport.TFramedTransportFactory()
            self.transport = self.transportFactory.getTransport(self.tsocket)
            self.protocol = TBinaryProtocol.TBinaryProtocol(self.transport)
            self.client = TestService.Client(self.protocol)
            self.transport.open()
        except Thrift.TException as e:
            self.logger.info(e)


class BaseService(object):

    def __init__(self):
        self.commonLogger = logging.getLogger('ads')
        self.header = "header111"

    def search_ads_list(self, request, account_id):
        self.smbClient.client.getFBAdsByAccount(param1, param2)

    def __enter__(self):
        self.smbClient = SmbClient()
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        self.smbClient.transport.close()

ech请求调用是这样的：

 with BaseService() as BaseSingleService:
            status, data, info = BaseSingleService.search_ads_list(
                request, account_id)

来自客户端的实际请求数量不够大，但需要一段时间。我收到如下错误：

Traceback (most recent call last):
  File "/home/xxx/xxx/src/smb_thrift_server.py", line 2200, in <module>
    server.serve()
  File "/home/xxx/xxx/venv3/lib/python3.5/site-packages/thrift/server/TNonblockingServer.py", line 350, in serve
    self.handle()
  File "/home/xxx/xxxx/venv3/lib/python3.5/site-packages/thrift/server/TNonblockingServer.py", line 310, in handle
    rset, wset, xset = self._select()
  File "/home/luban/smb_thrift_server/venv3/lib/python3.5/site-packages/thrift/server/TNonblockingServer.py", line 302, in _select
    return select.select(readable, writable, readable)
ValueError: filedescriptor out of range in select()

为什么每次收到响应后都会关闭客户端连接，而发生错误？

更新TestService以下代码：

from thrift.transport.TSocket import TTransportException
from thrift.Thrift import TException
from thrift.protocol import TBinaryProtocol, TCompactProtocol
from thrift.transport import TTransport
from thrift.transport import TSocket
from thrift import Thrift
from test_thrift.test_server import TestService


class SmbClient(object):
    def __init__(self):
        try:
            self.tsocket = TSocket.TSocket(settings.THRIFT_HOST, settings.THRIFT_PORT_PRODUCT)
            self.transportFactory = TTransport.TFramedTransportFactory()
            self.transport = self.transportFactory.getTransport(self.tsocket)
            self.protocol = TBinaryProtocol.TBinaryProtocol(self.transport)
            self.client = TestService.Client(self.protocol)
            self.transport.open()
        except Thrift.TException as e:
            self.logger.info(e)


class BaseService(object):

    def __init__(self):
        self.commonLogger = logging.getLogger('ads')
        self.header = "header111"

    def search_ads_list(self, request, account_id):
        self.smbClient.client.getFBAdsByAccount(param1, param2)

    def __enter__(self):
        self.smbClient = SmbClient()
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        self.smbClient.transport.close()