[Valgrind-users] program degradation

[齐玉华 <qi...@12...>]

 Hi, everyone.
 I try to use Valgrind to wrap some functions in target sotfwares such as php, libtiff. But i found that valgrind will slow down them significantly(up to 25 times slowwer), even if run valgrind with '--tool=none'. And as described in valgrind mannual, there should be 5 times slowwer than native running. I am confused, so anyone can help me to reduce the instrumentation-cost with some suggestions? I am waiting in hope for your advices. Thanks.
                     Yuhua Qi