[Linux-cachefs] Kernel 2.6.30-rc2

[David Howells]

Edward Konetzko <konetzed at quixoticagony.com> wrote:

> What should I look for

When I run my a tar over NFS with an empty cache, I see:

	Retrvls: n=21448 ok=0 wt=4197 nod=21448 nbf=0 int=0 oom=0
	Retrvls: ops=21448 owt=2483
	Stores : n=89990 ok=89990 agn=0 nbf=0 oom=0
	Stores : ops=21294 run=111284

Then when I run it again with a populated cache, I see:

	Retrvls: n=21448 ok=21447 wt=1841 nod=1 nbf=0 int=0 oom=0
	Retrvls: ops=21448 owt=0
	Stores : n=0 ok=0 agn=0 nbf=0 oom=0
	Stores : ops=0 run=0

On the stats about Retrievals, n=21448 is the number of retrievals requested,
ok=0 or ok=21447 is the number of retrievals actually satisfied from the
cache, and nod=21448 or nod=1 is the number of retrievals that gave ENODATA.
Note also that no stores were performes on the populated cache.

I'm slightly perplexed that I have one retrieval that persists in failing to
retrieve anything.  It is, however, something I've reduced to a read of a
single file, so I should be able to debug that.

Note that a 'retrieval' isn't a retrieval of a single page necessarily.  It
may be a request to retrieve multiple pages.

David