Date: Wed, 19 May 2021 04:52:35 UTC
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=251363 --- Comment #20 from Kirk McKusick <mckusick@FreeBSD.org> --- (In reply to Gunther Schadow from comment #19) The buffer cache is no longer a limited resource as it has become merged with the VM cache. Actually, the buffer cache is just a compatibility shim over the VM cache. The point is that the entire physical memory is managed by the VM cache. Most of the pages are associated with pages in filesystems and some are associated with running programs (stacks and heap pages). So whether you use those pages as part of NFS or the memory filesystem aggregated through the union filesystem, they are all coming from the same pool. Given the broken semantics and extra overhead of the union filesystem, you are better off letting NFS rather than the union and memory filesystem manage the pages. The role of the union filesystem is to allow the appearance of modification of read-only media like DVDs or CD-ROMs. -- You are receiving this mail because: You are the assignee for the bug.