I think having pure on-heap cache is good idea. Sergi
2017-04-05 12:52 GMT+03:00 Ilya Lantukh <ilant...@gridgain.com>: > Dmitry, > > 1. Setting an eviction policy should not be a mechanism to enable the > > on-heap cache. We already have eviction policies off-heap as well, and > they > > don't enable anything. On top of that, the eviction policy should not be > a > > requirement for the on-heap cache. User should still be able to enable > the > > on-heap cache, even if it grows indefinitely without evictions. We should > > have a more intuitive flag here. > > > It doesn't make any sence to me to enable on-heap cache without evictions: > it will result in having all data both in on-heap and off-heap memory. If > we want to support such use case, we should implement a separate on-heap > only mode with page memory disabled. > > > On Tue, Apr 4, 2017 at 7:15 PM, Dmitriy Setrakyan <dsetrak...@apache.org> > wrote: > > > Ilya, I looked at the Semyon's comments in the ticket, and I think I > agree > > with him on all counts. > > > > 1. Setting an eviction policy should not be a mechanism to enable the > > on-heap cache. We already have eviction policies off-heap as well, and > they > > don't enable anything. On top of that, the eviction policy should not be > a > > requirement for the on-heap cache. User should still be able to enable > the > > on-heap cache, even if it grows indefinitely without evictions. We should > > have a more intuitive flag here. > > > > 2. As far as the tests go, they should examine all the tests and adapt > them > > to the new behavior. I think we should have a replica of all off-heap > tests > > to test the scenario with on-heap caches. > > > > D. > > > > On Tue, Apr 4, 2017 at 8:12 AM, Ilya Lantukh <ilant...@gridgain.com> > > wrote: > > > > > Hi Igniters, > > > > > > Since review of IGNITE-4535 > > > <https://issues.apache.org/jira/browse/IGNITE-4535> implementation > > caused > > > some misunderstandings, I'd like to open a discussion here and see if > > > everyone agrees with the chosen approach or can suggest a better one. > > > > > > We are going to re-use existing EvictionPolicy mechanics to decide when > > > entry is going to be evicted from on-heap cache. If evictionPolicy == > > null, > > > we assume that there is no on-heap cache. One of suggested alternatives > > was > > > to have a separate boolean parameter that will enable on-heap cache. > > > > > > Another questionable decision was to remove tests for memory mode > > > variations. For example, we had GridCacheContinuousQueryAtomic > SelfTest, > > > GridCacheContinuousQueryAtomicOffheapTieredSelfTest and > > > GridCacheContinuousQueryAtomicOffheapValuesSelfTest that were testing > > the > > > same functionallity for ONHEAP_TIERED, OFFHEAP_TIERED and > OFFHEAP_VALUES > > > modes, respectively. Since those memory modes were removed, only > > > GridCacheContinuousQueryAtomicSelfTest was left and it now runs in > > > off-heap > > > mode without on-heap cache. One of suggestions was to add a new > subclass > > to > > > this test (and all other tests) that will run the same test case with > > > on-heap cache enabled. In my opinion, functionallity that is specific > for > > > on-heap cache should be tested in completely separate tests (which we > > > already have), and there is no need to run generic tests with every > > > possible configuration. > > > > > > What do you think? > > > > > > -- > > > Best regards, > > > Ilya > > > > > > > > > -- > Best regards, > Ilya >
