准备升级主站varnish到3.0.1，主要看上最后一句了

Summary of changes from 3.0.0 to 3.0.1

• Objects with grace and keep set were mistakenly seen as candidates for the shortlived storage, but would not be cleaned up quickly, something that manifested as if there was a memory leak. This is now fixed.

• When multiple clients were waiting for an object, all clients would be woken up when an object became available, leading to stuck threads. This has now been fixed

• A bug in how XML entities were handled with ESI has been fixed

• The documentation has seen numerous updates

• varnishncsa is now more stable and has support for showing arbitrary request and response fields、

期待varnishncsa有更好的表现