ignite-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Alexey Goncharuk <alexey.goncha...@gmail.com>
Subject Re: Data regions on client nodes
Date Wed, 08 Aug 2018 13:05:35 GMT
I do not mind making this change, but note that the reason for non-lazy
region allocation is the need to gracefully handle OOME errors during cache
start. When a region is pre-allocated, no OOME can happen.

If a region is allocated dynamically, then all errors that happened during
the node start before should be properly handled (a client node must be
stopped, but cache creation should proceed).

пт, 27 июл. 2018 г. в 20:04, Valentin Kulichenko <
valentin.kulichenko@gmail.com>:

> Ticket created: https://issues.apache.org/jira/browse/IGNITE-9113
>
> -Val
>
> On Fri, Jul 27, 2018 at 5:59 AM Dmitry Pavlov <dpavlov.spb@gmail.com>
> wrote:
>
> > Maxim, thank you.
> >
> > If it seems it is technically possible, we can file ticket for this
> change.
> >
> > I find this proposal reasonable, change makes perfectly sense to me.
> >
> > We can wait Alex G. feedback on this change before starting actual
> > implementation. It can take for a while, because he is travelling now.
> >
> > пт, 27 июл. 2018 г. в 14:35, Maxim Muzafarov <maxmuzaf@gmail.com>:
> >
> > > 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.spb@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 <maxmuzaf@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 <
> > dsetrakyan@apache.org
> > > >:
> > > > >
> > > > > > On Sat, Jul 21, 2018 at 5:22 AM, Valentin Kulichenko <
> > > > > > valentin.kulichenko@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
> > >
> >
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message