Caching question + "smart" autowarming

[Jon Baer <jo...@gmail.com>]

I have a few general questions re: caching ...

1. The FastLRU cache in 1.4 seems promising but is there a more  
comprehensive list of benefits?  Is there a huge speed boost for using  
this type of cache?

2. What are the possibilities to using external caches for scaling out  
like memcachedb or redis?  Is this just a matter of interfacing  
SolrCache?

3. Does the autowarming of a new searcher use any type of statistics  
on the old one?  How does it figure what to pull from old cache if  
autowarmCount is set low?  IE can I get the most popular or is it  
ordered based on something in the docs themselves?

Thanks.

- Jon

Re: Caching question + "smart" autowarming

[Yonik Seeley <yo...@lucidimagination.com>]

On Fri, Mar 13, 2009 at 12:58 PM, Jon Baer <jo...@gmail.com> wrote:
> I have a few general questions re: caching ...
>
> 1. The FastLRU cache in 1.4 seems promising but is there a more
> comprehensive list of benefits?  Is there a huge speed boost for using this
> type of cache?

It simply removes contention for readers.... you would see gains under
high load and when the cache hit rate is very high (and esp if there
are multiple cache checks per request... like the enum faceting method
does with the filter cache).

> 2. What are the possibilities to using external caches for scaling out like
> memcachedb or redis?  Is this just a matter of interfacing SolrCache?

Would be doable, but slower unless the circumstances were very special.

> 3. Does the autowarming of a new searcher use any type of statistics on the
> old one?  How does it figure what to pull from old cache if autowarmCount is
> set low?  IE can I get the most popular or is it ordered based on something
> in the docs themselves?

For our LRU caches, it's the most recently used items.

-Yonik
http://www.lucidimagination.com