Hi Denis, I've updated the section in relation to your questions, please see https://cwiki.apache.org/confluence/display/IGNITE/Ignite+Durable+Memory+-+under+the+hood#IgniteDurableMemory-underthehood-IgniteDurableMemory
I’ve also moved paragraph related to page offset calculation and usage in files into second article (PDS) Sincerely, Dmitriy Pavlov пт, 1 сент. 2017 г. в 19:50, Denis Magda <dma...@apache.org>: > Dmitriy, > > First of all, thanks for putting this low level details on paper! Current > and future community members will be grateful to you. > > Second, let me be a reviewer of the page and suggest some improvements. > Until the review is over I would encourage us to hold on with any public > announcements such as blog post. > > I’ve reviewed and edited Ignite Durable Memory section ( > https://cwiki.apache.org/confluence/display/IGNITE/Ignite+Durable+Memory+-+under+the+hood#IgniteDurableMemory-underthehood-IgniteDurableMemory > < > https://cwiki.apache.org/confluence/display/IGNITE/Ignite+Durable+Memory+-+under+the+hood#IgniteDurableMemory-underthehood-IgniteDurableMemory>). > Please address the questions below and I’ll move on with the new sections > afterwards. > > 1) "Different caches and its partitions bring more complex addressing > scheme but it is still possible to map from page ID to position in > particular file: pageId => file + offset in this file”. > > Probably this appears too early in the doc because above we just > introduced page ID notion with durable memory and now we’re talking about > some files? Are these files of ignite persistence? What if the persistence > is disabled? Honestly, the sentence gets out of the story context. > > > 2) "Also, the tree pages can be merged into one if < 50% of space is used.” > > 50% of the whole memory available? Please clarify. > > > 3) "There is one page ID table per memory segment.” > > It’s the same segment as it’s described in the main doc, right? > https://apacheignite.readme.io/docs/memory-architecture#section-memory-segment > < > https://apacheignite.readme.io/docs/memory-architecture#section-memory-segment > > > > > 4) "within unsafe segment” > > If we want to mention “usafe” here we need to explain what that is. > > 5) "If memory amount less than whole index size, Ignite still can operate.” > > How do we define “index size”? Is this the page size? > > > — > Denis > > > > On Aug 30, 2017, at 8:24 AM, Dmitry Pavlov <dpavlov....@gmail.com> > wrote: > > > > Hi Igniters, > > > > > > I am glad to introduce two new wiki articles. These articles contain > > high-level description of > > > > - Ignite Durable Memory ( > > > https://cwiki.apache.org/confluence/display/IGNITE/Ignite+Durable+Memory+-+under+the+hood > > ) > > > > - and Ignite Persistent Store ( > > > https://cwiki.apache.org/confluence/display/IGNITE/Ignite+Persistent+Store+-+under+the+hood > > ) > > > > These articles cover basic principles and internal design. Pages may be > > useful for new contributors during start of working with persistent store > > code base. > > > > > > I would like to thank all contributors who helped me with my questions. > > Their answers and support made it possible to start this description. > > > > > > I will appreciate any feedback and questions. Suggestions and edits are > > welcome, of course. > > > > > > Sincerely, > > > > Dmitriy Pavlov > >
