[OpenAFS-devel] PATCH: limit afsd auto-tuning to 500000 files

[Jeffrey Hutzelman]

On Tuesday, August 23, 2005 08:23:13 PM -0400 chas williams - CONTRACTOR 
<chas@cmf.nrl.navy.mil> wrote:

> In message <475D0B15E1CC68BBF87A7B2D@sirius.fac.cs.cmu.edu>,Jeffrey
> Hutzelman writes:
>> 67%-full assumption is incorrect.  Perhaps we were too conservative in
>> bumping the average filesize assumption from 10K to 32K, and it should
>> really be bigger.
>
> i dont believe that there should be linear relationsip between the
> average filesize and the cache size.  when a user increases the disk
> cache, the more kernel memory is not available.

Well, right now we use two numbers.  One is a constant; the other is a 
function of the chunk size.  It sounds like you're arguing for eliminating 
the constant, or at least limiting its effect as the cache size grows very 
large.  Fine, but without data, how do we decide where to draw the line? 
With a small cache and a large chunk size, we need that constant to ensure 
we have enough files.

-- Jeff