See below...
On Tue, Feb 7, 2012 at 8:21 AM, Pranav Prakash <pra...@gmail.com> wrote:
> Based on the hit ratio of my caches, they seem to be pretty low. Here they
> are. What are typical values of yours production setup? What are some of
> the things that can be done to improve the ratios?
>
> queryResultCache
>
> lookups : 3234602
> hits : 496
> hitratio : 0.00
> inserts : 3234239
> evictions : 3230143
> size : 4096
> warmupTime : 8886
> cumulative_lookups : 3465734
> cumulative_hits : 526
> cumulative_hitratio : 0.00
> cumulative_inserts : 3465208
> cumulative_evictions : 3457151
>
>
This is not unusual, but there's also not much reason to give this much
memory in your case. This is the cache that is hit when a user pages
through result set. Your numbers would seem to indicate one of two things:
1> your window is smaller than 2 pages, see solrconfig.xml,
<queryResultWindowSize>
or
2> your users are rarely going to the next page.
this cache isn't doing you much good, but then it's also not using that
much in the way of resources.
> documentCache
>
> lookups : 17647360
> hits : 11935609
> hitratio : 0.67
> inserts : 5711851
> evictions : 5707755
> size : 4096
> warmupTime : 0
> cumulative_lookups : 19009142
> cumulative_hits : 12813630
> cumulative_hitratio : 0.67
> cumulative_inserts : 6195512
> cumulative_evictions : 6187460
>
Again, this is actually quite reasonable. This cache
is used to hold document data, and often doesn't have
a great hit ratio. It is necessary though, it saves quite
a bit of disk seeks when servicing a single query.
>
> fieldValueCache
>
> lookups : 0
> hits : 0
> hitratio : 0.00
> inserts : 0
> evictions : 0
> size : 0
> warmupTime : 0
> cumulative_lookups : 0
> cumulative_hits : 0
> cumulative_hitratio : 0.00
> cumulative_inserts : 0
> cumulative_evictions : 0
>
Not doing much in the way of faceting, are you?
>
> filterCache
>
> lookups : 30059278
> hits : 28813869
> hitratio : 0.95
> inserts : 1245744
> evictions : 1245232
> size : 512
> warmupTime : 28005
> cumulative_lookups : 32155745
> cumulative_hits : 30845811
> cumulative_hitratio : 0.95
> cumulative_inserts : 1309934
> cumulative_evictions : 1309245
>
>
Not a bad hit ratio here, this is where
fq filters are stored. One caution here;
it is better to break out your filter
queries where possible into small chunks.
Rather than write fq=field1:val1 AND field2:val2,
it's better to write fq=field1:val1&fq=field2:val2
Think of this cache as a map with the query
as the key. If you write the fq the first way above,
subsequent fqs for either half won't use the cache.
Best
Erick
>
>
> *Pranav Prakash*
>
> "temet nosce"
>
> Twitter <http://twitter.com/pranavprakash> | Blog <http://blog.myblive.com> |
> Google <http://www.google.com/profiles/pranny>
