Re: Exposing cache statistics

[Steve Dickson <SteveD@redhat.com>]

Kevin Constantine wrote:
> Trond Myklebust wrote:
>> On Wed, 2009-04-15 at 13:30 -0700, Kevin Constantine wrote:
>>> Has there been any effort to expose caching statistics to the end
>>> user?   On the client-side, it would be useful to see how much data
>>> is being re-used from cache vs data that gets retrieved over the
>>> wire.  Similarly on the server side, it would be nice to see how much
>>> data is being served from cache vs having to pull the data from disk.
>>>
>>> Just wondering if anyone started anything to expose this sort of
>>> information.
>>
>> See the nfs-iostat tool in the nfs-utils package:
>>
>>   
>> http://git.linux-nfs.org/?p=steved/nfs-utils.git;a=tree;f=tools/nfs-iostat;h=929e303cc762a68dfd01546f5150eb294274164e;hb=refs/heads/master
>>
>>
>> Note that you need a 2.6.17 kernel or newer.
>>
>> Cheers
>>   Trond
> 
> Thanks Trond-
> 
> It seems like nfs-iostat is displaying the number of pages that are
> being written to the read/write caches (i'm only looking at the
> client-side at the moment), and what I'm interested in is the ratio of
> pages being read from cache vs data being fetched from the server.
> 
> Is there any documentation on the layout of /proc/self/mountstats?
No, unfortunately not... 

steved.