@@ -218,6 +218,10 @@ class Config(object):

     throttle_max = 100

     public_url_use_https = False

     connection_pooling = True

+    # How long a connection can be kept idle in the pool and still be alive

+    # Currently, aws s3 closes connections that are idle for 20 seconds or

+    # longer, but 16s is used here by default to be safe.

+    connection_max_age = 16

     ## Creating a singleton

     def __new__(self, configfile = None, access_key=None, secret_key=None, access_token=None):

@@ -14,8 +14,10 @@ if sys.version_info >= (3, 0):

 else:

     from .Custom_httplib27 import httplib

 import ssl

-from threading import Semaphore

+

 from logging import debug

+from threading import Semaphore

+from time import time

 try:

     # python 3 support

     from urlparse import urlparse

@@ -238,18 +240,19 @@ class http_connection(object):

                 debug(u'proxied HTTPConnection(%s, %s)', cfg.proxy_host, cfg.proxy_port)

                 # No tunnel here for the moment

+        self.last_used_time = time()

 class ConnMan(object):

     _CS_REQ_SENT = httplib._CS_REQ_SENT

     CONTINUE = httplib.CONTINUE

     conn_pool_sem = Semaphore()

     conn_pool = {}

-    conn_max_counter = 800    ## AWS closes connection after some ~90 requests

+    conn_max_counter = 800  ## AWS closes connection after some ~90 requests

     @staticmethod

-    def get(hostname, ssl = None):

+    def get(hostname, ssl=None):

         cfg = Config()

-        if ssl == None:

+        if ssl is None:

             ssl = cfg.use_https

         conn = None

         if cfg.proxy_host != "":

@@ -261,9 +264,19 @@ class ConnMan(object):

         ConnMan.conn_pool_sem.acquire()

         if conn_id not in ConnMan.conn_pool:

             ConnMan.conn_pool[conn_id] = []

-        if len(ConnMan.conn_pool[conn_id]):

+        while ConnMan.conn_pool[conn_id]:

             conn = ConnMan.conn_pool[conn_id].pop()

-            debug("ConnMan.get(): re-using connection: %s#%d" % (conn.id, conn.counter))

+            cur_time = time()

+            if cur_time < conn.last_used_time + cfg.connection_max_age \

+               and cur_time >= conn.last_used_time:

+                debug("ConnMan.get(): re-using connection: %s#%d"

+                      % (conn.id, conn.counter))

+                break

+            # Conn is too old or wall clock went back in the past

+            debug("ConnMan.get(): closing expired connection")

+            ConnMan.close(conn)

+            conn = None

+

         ConnMan.conn_pool_sem.release()

         if not conn:

             debug("ConnMan.get(): creating new connection: %s" % conn_id)

@@ -278,7 +291,8 @@ class ConnMan(object):

     def put(conn):

         if conn.id.startswith("proxy://"):

             ConnMan.close(conn)

-            debug("ConnMan.put(): closing proxy connection (keep-alive not yet supported)")

+            debug("ConnMan.put(): closing proxy connection (keep-alive not yet"

+                  " supported)")

             return

         if conn.counter >= ConnMan.conn_max_counter:

@@ -292,10 +306,14 @@ class ConnMan(object):

             debug("ConnMan.put(): closing connection (connection pooling disabled)")

             return

+        # Update timestamp of conn to record when was its last use

+        conn.last_used_time = time()

+

         ConnMan.conn_pool_sem.acquire()

         ConnMan.conn_pool[conn.id].append(conn)

         ConnMan.conn_pool_sem.release()

-        debug("ConnMan.put(): connection put back to pool (%s#%d)" % (conn.id, conn.counter))

+        debug("ConnMan.put(): connection put back to pool (%s#%d)"

+              % (conn.id, conn.counter))

     @staticmethod

     def close(conn):