cx_Oracle + oracle实例客户端11g挂起

Question

下一步代码在instant client 10g上工作正常，但在使用oracle instant client 11g时挂起，挂起在pool.release(conN)上，

import time
print '---------------------------------'
import cx_Oracle
print cx_Oracle.clientversion()
time.sleep(1)
pool = cx_Oracle.SessionPool('login', 'pass', "dbserver:1521/db", 1, 6, 2)
pool.timeout = 60
con11 = pool.acquire()
con12 = pool.acquire()
con13 = pool.acquire()
con14 = pool.acquire()
con15 = pool.acquire()
pool.release(con11)
pool.release(con12)
pool.release(con13)
pool.release(con14)
pool.release(con15)
for i in xrange(100000):
    print '-=-' + str(i) + '-=-'
    print str(pool.opened) + " " + str(pool.busy)
    con1 = pool.acquire()
    cursor = con1.cursor()
    cursor.execute("SELECT * FROM DUAL")
    count = cursor.fetchall()[0][0]
    cursor.close()
    print str(pool.opened) + " " + str(pool.busy)
    con2 = pool.acquire()
    cursor = con2.cursor()
    cursor.execute("SELECT * FROM DUAL")
    count = cursor.fetchall()[0][0]
    cursor.close()
    print str(pool.opened) + " " + str(pool.busy)
    con3 = pool.acquire()
    cursor = con3.cursor()
    cursor.execute("SELECT * FROM DUAL")
    count = cursor.fetchall()[0][0]
    cursor.close()
    print str(pool.opened) + " " + str(pool.busy)
    t1 = time.time()
    pool.release(con3)
    t2 = time.time()
    print t2 - t1
    print str(pool.opened) + " " + str(pool.busy)
    t1 = time.time()
    pool.release(con2)
    t2 = time.time()
    print t2 - t1
    t1 = time.time()
    pool.release(con1)
    t2 = time.time()
    print t2 - t1
    print str(pool.opened) + " " + str(pool.busy)
print '---------------------------------'

PS:我看了一下cx_Oracle的源代码，它的手在sesionpool.c在线

    status = OCISessionRelease(connection->handle,
            connection->environment->errorHandle, NULL, 0, mode);

有没有办法解决这个问题？

PPS:操作系统Windows XP和2008R2

Answer 1

http://cx-oracle.sourceforge.net/html/session_pool.html

注此对象是DB API的扩展，仅在Oracle 9i中可用。

Answer 2

我昨天也有同样的症状:在一个带有会话池的多线程应用程序中，有时释放会话会挂起长达2分钟。

您可能遇到了以下Oracle错误之一：

错误10157313 -使用OCISessionRelease会话池时，CPU使用率过高且性能低下(文档ID 10157313.8)

错误10157313 :使用11.2时，OCI会话池会增加CPU使用率，并需要很长时间才能释放

有关详情，请参阅Oracle Metalink。

将Oracle客户端软件更新到11.2.0.3或更高版本(例如InstantClient 11.2.0.3)似乎会有所帮助。