Guys, I can miss some details, but at the first glance we have everething we need to defer region memory allocation if it has no cache groups assignments. And it doesn't matter where it happens on client or server nodes.
Currently region memory allocation happens at exchange future init method. At the node startup method initCachesOnLocalJoin executes. This method resposnible for memory allocation (through initiating cache managers) and it also starts caches. So, at this point we have all existing caches descriptors and can find out which cache matches which region to defer some regions initialization to the moment when newly cache assings to this region (happend at onCacheChangeRequest). Please, сorrect me if I'm wrong and missing something. On Wed, 25 Jul 2018 at 19:32 Dmitry Pavlov <dpavlov....@gmail.com> wrote: > Hi Maxim, > > thank you for stepping in. How do you think, is it possible to check cache > assignment to region at stage of memory allocation? > > Sincerely, > Dmitriy Pavlov > > ср, 25 июл. 2018 г. в 18:22, Maxim Muzafarov <maxmu...@gmail.com>: > > > Folks, > > > > I've checked memory allocation. It looks like we are allocating memory > only > > on the first exchange future init on local join occurs on node. Also, > seems > > like we are allocating only the first chunk of memory (not the whole > bunch) > > and it calculates as: > > > > Math.max((maxSize - startSize) / (SEG_CNT - 1), 256L * 1024 * 1024) > > > > But, I'm agree with Val. It's better to allocate memory only when when > > the first cache assigned to this region. > > > > > > > > Also, It seems like we have some problem with user notification about > > available > > physical resources. For client nodes method requiredOffheap() returns > > always > > zero [1]. That's why WARN message shown here [2] would be not not quite > > right > > if we have a lot of client nodes in cluster. > > > > > > [1] > > > > > https://github.com/apache/ignite/blob/master/modules/core/src/main/java/org/apache/ignite/internal/managers/discovery/GridDiscoveryManager.java#L1501 > > [2] > > > > > https://github.com/apache/ignite/blob/master/modules/core/src/main/java/org/apache/ignite/internal/IgniteKernal.java#L1489 > > > > сб, 21 июл. 2018 г. в 14:15, Dmitriy Setrakyan <dsetrak...@apache.org>: > > > > > On Sat, Jul 21, 2018 at 5:22 AM, Valentin Kulichenko < > > > valentin.kuliche...@gmail.com> wrote: > > > > > > > Actually, I would go even further: only allocate a data region on a > > node > > > > when the first cache assigned to this region is deployed on that > node. > > > > Because issue is broader than client nodes and local caches. One can > > have > > > > server nodes without any caches as well - running only services, for > > > > example. > > > > > > > > > > It would be great if this was possible, but to my knowledge, regions > need > > > to be allocated on startup. > > > > > > Alexey Goncharuk, do you have any suggestions on this? > > > > > > D. > > > > > -- > > -- > > Maxim Muzafarov > > > -- -- Maxim Muzafarov
