varnish delete least requested files

I see that varnish can be configured to set -smalloc or -sfile with a certain size.

I want to set a file cache of 1G such that least requested files are deleted first when cache is full. Is this possible in varnish? Is there another reverse proxy tool that can do this?

Varnish uses “least recently used” (LRU), for more information see: https://www.varnish-cache.org/trac/wiki/ArchitectureLRU

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