我从其他论坛上得到的： a) your internet connection was slow the first time, and not the others. (Perhaps someone else was downloading at the time.)(b) you're using a caching proxy, and the first time you fetched the files, it cached them; the subsequent times, it used the cached copies.(c) you did all five runs in the same JVM instance, and the first run had all the overhead of class loading & JIT compilation.(d) something else was running on your machine when you did the first test run, but not on the remaining runs - a cron job for database update, for example.我认为 只有b c，其他我知道现在没有人用。如何知道我的是caching proxy我用的是学校的机器。
a) your internet connection was slow the first time, and not the
others. (Perhaps someone else was downloading at the time.)(b) you're using a caching proxy, and the first time you fetched
the files, it cached them; the subsequent times, it used the
cached copies.(c) you did all five runs in the same JVM instance, and the first
run had all the overhead of class loading & JIT compilation.(d) something else was running on your machine when you did the
first test run, but not on the remaining runs - a cron job for
database update, for example.我认为 只有b c，其他我知道现在没有人用。如何知道我的是caching proxy我用的是学校的机器。