Hard-source-wepback-plugin might slows down HMR

[AllenHuang777]

It seems that hard-source-wepback-plugin would slow down the HMR. Our local test shows that HMR would takes more 2-3s if we use hard-source-webpack-plugin. Is there any ways to avoid affecting HMR performance？ BTW, you gays do create a great webpack-plugin I've ever seem!