As long as new branches — to use your analogy — are in memory, why does it matter that a few others are too? The least recently used branches will automatically (LRU) be purged from memory if space is needed for new branches.
In fact, if you’re worried about available memory, a time based eviction policy won’t work. What if you expect to have 100 branches and size your cluster appropriately. Suddenly, 1000 branches are created. Boom! With a space-based eviction policy — as is the default with Ignite native persistence — that works just fine. You could create a cache with an eviction policy. When the records are deleted after a week, you can have a process listening to delete events and copy the record to a different cache in a small data region. So what you’re asking for is possible, it’s just more complicated and less effective than the alternative. > On 19 Jan 2021, at 14:04, Ryan Trollip <ryanonthebe...@gmail.com> wrote: > > Stephen > > Let's use an analogy of projects in source control. Let's say we have a very > active community of developers, they are creating 100 new branches a day. > Each branch has a few thousand objects and associated properties etc. but > these developers don't clean up by deleting branches. > We want new branches to be cached in memory and available high performance > read and write, but older branches to go to disk to save on memory hardware > needs, since many are abandoned. > The policy could read something like this: Branches that have not been > accessed in 1 week, move to disk. On branch access, if on disk, move back to > RAM. > > Thanks > Ryan > > On Tue, Jan 19, 2021 at 2:33 AM Stephen Darlington > <stephen.darling...@gridgain.com <mailto:stephen.darling...@gridgain.com>> > wrote: > I guess I’m still not clear why you need to explicitly remove them from > memory. > > By virtue of using native persistence, they’re already on disk. If you load > new data, the old entries will eventually be flushed from memory (but remain > on disk). What do you gain by removing entries from memory at a specific time? > > Regards, > Stephen > > > On 19 Jan 2021, at 06:02, Naveen <naveen.band...@gmail.com > > <mailto:naveen.band...@gmail.com>> wrote: > > > > Hi Stephen > > > > on the same mail chain, we also data like OTP (one time passwds) which are > > no relevant after a while, but we dont want to expire or delete them, just > > get them flushed to disk, like wise we do have other requirements where data > > is very relevant only for a certain duration, later on its not important. > > Thats the whole idea of exploring eviction policies > > > > Naveen > > > > > > > > -- > > Sent from: http://apache-ignite-users.70518.x6.nabble.com/ > > <http://apache-ignite-users.70518.x6.nabble.com/> > >
