curr_items never decreases

[Stephen Woodbridge]

Mike Damm wrote:
> Stephen Woodbridge wrote:
> 
>> Right, this is important to understand if the cache is large enough. 
>> If my business rules say the cache items should be available for 7 
>> days, I need to know if I am pushing items out of the cache before 
>> that time. So some stats on the number of items bumped out of the 
>> cache before they expired and the average number of sec before they 
>> expired. These stats should ignore items that have no expiry or just 
>> could the number of items with no expiry that are purged.
>>
>> This would give me a good indication of how right sized the cache is 
>> and how much I might need to add to it to bring it back in line with 
>> the business rules.
> 
> 
> I'm not quite sure what you mean by "business rules," but if your system 
> depends on things existing in the cache for 7 days, I think you might 
> want to step back and take a look at your overall architecture.

Yeah, we have been looking at it. Items should be available for about 7 
days in the cache. Nothing breaks catastrophically if it leaves sooner, 
but clients session are no longer available and they will need to create 
a new session. We are happy to size it for this, but I would like to get 
it close initially and would like to know how much more I need to add to 
get it right as load expands the demands on the cache.

-Steve