Performance impact when `ping_before_execute` is turned on

[wenhaocs]

This affects 5.2.0

To avoid the issues caused by #398, test_on_borrow must be disabled and ping_before_execute must be enabled. However, this means that a ping will be performed before every execute call. Under high QPS, what would the performance overhead be?

[Nicole00]

该场景鲁班在LDBC Benchmark上测试过，跑ldbc时 开启java sdk的test on borrow 会导致每次执行ldbc的请求前都会进行ping动作。 经测试，开启和不开启test_on_borrow 对benchmark的分值几乎没影响。cc @shanlai

[shanlai]

该场景鲁班在LDBC Benchmark上测试过，跑ldbc时 开启java sdk的test on borrow 会导致每次执行ldbc的请求前都会进行ping动作。 经测试，开启和不开启test_on_borrow 对benchmark的分值几乎没影响。cc @shanlai

基于最新的nightly做了验证，开启和关闭时，QPS持平。详见对比记录：http://192.168.15.14/#/execution/detail?id=6474&tab=comparison&compareId=6471

[xiajingchun]

@wenhaocs ok to close this one?

[wenhaocs]

Good to close. Thank you!