On Thu, Sep 17, 2015 at 2:58 AM, Alexey Kuznetsov <[email protected]> wrote:
> If it is not snapsohtable there could be at least one use-case: populated > once and never changed cache. > For example for some analytics. > User populate 100500 entries into cache, build index and run 100500 > queries. > > I agree with Alexey. If disabling snapshots provides any kind of performance optimization for us, we should probably support 2 modes, snapshotttable and not, at least at configuration level. I am sure that there are plenty of users that don't care about snapshots, even in the presence of concurrent updates. >From the feature standpoint, I don't see anything in CQEngine that Ignite does not have in its SQL queries. However, from the performance standpoint, I still think that it is worthwhile to check out the CQ Engine code and see if we there is anything we can borrow. > On Thu, Sep 17, 2015 at 6:27 AM, Sergi Vladykin <[email protected]> > wrote: > >> Thanks for the pointers! >> The main difficulty at Ignite side is that we need >> index data structure to be snapshotable with O(1) complexity and of course >> without copying of the whole thing, so I'm not sure if we will be able >> to use something from there as is. >> But nevertheless CQEngine at least deserves to be investigated for ideas >> about data structures. >> >> Sergi >> >> >> 2015-09-17 1:19 GMT+03:00 vkulichenko <[email protected]>: >> >>> javadevmtl wrote >>> > Yeah it's perforamance is crazy. I hadn't experienced any "buggy" >>> issues >>> > when i tried. it also has off-heap otion now also. But I find the >>> concept >>> > of O(1) indexes very interesting... >>> >>> I think that O(1) is achievable only for hash indexes and therefore can >>> be >>> used only for equality queries. This is a very rare case in SQL and can >>> barely be treated as a replacement of tree indexes. >>> >>> -Val >>> >>> >>> >>> -- >>> View this message in context: >>> http://apache-ignite-users.70518.x6.nabble.com/Btw-anyone-heard-of-CQ-engine-tp1421p1425.html >>> Sent from the Apache Ignite Users mailing list archive at Nabble.com. >>> >> >> > > > -- > Alexey Kuznetsov > GridGain Systems > www.gridgain.com >
