[OpenAFS] Questions regarding `afsd` caching arguments (`-dcache` and `-files`)

Ciprian Dorin Craciun ciprian.craciun@gmail.com
Fri, 8 Mar 2019 18:19:55 +0200


I have two small questions about the cache management of `asfd`.  (The
documentation isn't very explicit.)

(In both cases I'm speaking about disk-based cache.)

(A) Using `-dcache 128` with a `-chunksize 10` (i.e. 1MiB) for a
disk-based cache, would actually allocate 128 MiB from kernel memory
(i.e. the product of the two)?  It is unclear from the documentation.
(Although I would infer yes, based on the description of memory based
cache.)

(B)  Using `-files` and `-chunksize` so that their product is larger
than `-blocks` means that the cache can hold up to as many `-files`
actual AFS files, but their total size can't be larger than `-blocks`?
 (I.e. if one has a cell with lots of small files, it is OK to
configure a largish `-chunksize` and `-files` because they will be
cached up to `-blocks`.)

Thanks,
Ciprian.