Hello Denis,

There is a small piece of documentation in *MemoryConfiguration *class,
although I think it should be moved to *MemoryPolicyConfiguration *and
detailed a lot.

I'm going to write some documentation soon about validation rules that are
applied to memory policies configuration (there are some restrictions about
reserved name, default memory policy name and so on). I'll let you know
when it is done.

About your question: MemoryPolicy offheap regions were never supposed to be
expandable. If user uses default MemoryPolicy (which in fact doesn't have
any eviction algorithm configured) he/she will get OutOfMemory error when
default size is exhausted.

This OOM behavior was left intentionally to be consistent with the previous
behavior as configuring some default eviction policy on default
MemoryPolicy may lead to data loss and it is better to communicate wrong
memory configuration to user even with OOM than silently drop some cached
values.

Thanks,
Sergey.

On Mon, Apr 17, 2017 at 12:01 AM, Denis Magda <dma...@apache.org> wrote:

> Guys,
>
> I’ve been working on the documentation for page memory [1]. The doc is
> still in progress and it will be more profound with code snippets and
> pictures int the end, so don’t pay to the fact that it mostly consists of
> dry text only.
>
> So, the question is different. Presently, javadoc part is useless (and
> will be written by me as well) and it’s not clear what’s the default
> behavior of the page memory that has only one memory policy (default) that
> instantiates a single memory region. Looking at the code I see that the
> default police creates 1 GB region that should be expandable because the
> policy doesn’t define an eviction algorithm. It means that if my app goes
> beyond 1 GB then the page memory will take more memory from an OS. Is my
> understanding correct?
>
> [1] https://apacheignite.readme.io/docs/page-memory <
> https://apacheignite.readme.io/docs/page-memory>
>
> —
> Denis

Reply via email to