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From Sergi Vladykin <sergi.vlady...@gmail.com>
Subject Re: SQL Performance indexing performance on-heap vs off-heap
Date Wed, 16 Sep 2015 18:19:09 GMT
Regardless of whether it is off-heap or on-heap, performance of indexes
*will* degrade with cache growth and this is unavoidable.

For better understanding: cache is basically a hash map with O(1) operation
complexity,  SQL index is basically an AVL tree which has O(log(N))
operation complexity. So if you don't use indexes, you have O(1), if you do
then O(log(N)) which gets worse with bigger N.

Sergi


2015-09-16 20:11 GMT+03:00 javadevmtl <java.dev.mtl@gmail.com>:

> Sorry Dimitry, switching to primitives definitely helped me save on heap
> usage, but not performance. The issue I reported with off-heap is still
> true, it's alot slower then on-heap and gets slower over time as the cache
> grows...
>
>
>
> --
> View this message in context:
> http://apache-ignite-users.70518.x6.nabble.com/SQL-Performance-indexing-performance-on-heap-vs-off-heap-tp1352p1416.html
> Sent from the Apache Ignite Users mailing list archive at Nabble.com.
>

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