Hm... why not just return the key count? Can we really have nulls in the near cache?
On Fri, Jun 23, 2017 at 8:25 PM, Mikhail Cherkasov <mcherka...@gridgain.com> wrote: > Hi all, > > GridCacheAdapter#size() has O(n) complexity and this can lead for delays > during metric collection( https://issues.apache.org/ > jira/browse/IGNITE-5521 > ). > It validates all elements in near cache while count them, so it takes O(n), > but java doc requires: > > "Gets the number of all entries cached on this node. This method will > return the count of all cache entries and has O(1) complexity on base > IgniteInternalCache. It is essentially the size of cache key set and is > semantically identical to {Cache.keySet().size(). > NOTE: this operation is not distributed and returns only the number of > entries cached on this node." > > > I see two solutions for this: > > 1. add special method for metrics that will have relaxed accuracy, but with > O(1) complexity > I implemented this solution there: > https://github.com/gridgain/apache-ignite/commit/ > a68dd81090884d07bd737cbbf48e5f64e9cd27ec > > 2. or completely remove entries validation for size method. > > What is better solution? Thoughts? > > -- > Thanks, > Mikhail. >
