Cache storage overflow

[Avariya]

Problem:
If you are using Etag or Last-Modified validation models - it is a big risk of cache overflow.
E.g.: you are updating response every second and as a result update Last-Modified header every second.
The record will be added to cache storage and never will be removed as it has no TTL.
As Etag header is new - record with a new key will be created.

Probable solution:
Remove headers mentioned above from response headers before generating a cache key. E.g. at PrivateCacheStrategy:123

[Avariya]

Looks like it is not a reason.
Only vary headers are in list