Vladimir, 80% allocation approach was implemented in AI 2.0. I personally explained users on the forums its behavior.
Actually, dynamic vs static memory allocation scenarios were analyzed and discussed long time ago and eventually we decided to go for with the former: http://apache-ignite-developers.2346864.n4.nabble.com/Page-Memory-behavior-with-default-memory-policy-td16716.html I don’t see anything harmful with the dynamic allocation. Operating systems are sophisticated enough to leverage from swapping when there are to many processes running that complete for RAM. Never had any issue with this on my local laptop. There will be even more benefits for production scenarios when a server has a plenty of RAM available and not that many applications running. If to stick to the static allocation approach it will require to set a specific value all the time depending on a hardware. This is what we wanted to avoid. — Denis > On Aug 1, 2017, at 2:03 PM, Vladimir Ozerov <voze...@gridgain.com> wrote: > > Denis, > No doubts you haven't heard about it - AI 2.1 with persistence, when 80% of > RAM is allocated right away, was released several days ago. How do you > think, how many users tried it already? > > Guys, > Do you really think allocating 80% of available RAM is a normal thing? Take > your laptop and check how many available RAM you have right now. Do you fit > to remaining 20%? If not, then running AI with persistence with all > defaults will bring your machine down. This is insane. We shold allocate no > more than 1Gb, so that user can play with it without any problems. > > On Tue, Aug 1, 2017 at 10:26 PM, Denis Magda <dma...@apache.org> wrote: > >> My vote goes for option #1 too. I don’t think that 80% is too aggressive >> to bring it down. >> >> IGNITE-5717 was created to fix the issue of the 80% RAM allocation on 64 >> bit systems when Ignite works on top of 32 bit JVM. I’ve not heard of any >> other complaints in regards the default allocation size. >> >> — >> Denis >> >>> On Aug 1, 2017, at 10:58 AM, dsetrak...@apache.org wrote: >>> >>> I prefer option #1. >>> >>> D. >>> >>> On Aug 1, 2017, 11:20 AM, at 11:20 AM, Sergey Chugunov < >> sergey.chugu...@gmail.com> wrote: >>>> Folks, >>>> >>>> I would like to get back to the question about MemoryPolicy maxMemory >>>> defaults. >>>> >>>> Although MemoryPolicy may be configured with initial and maxMemory >>>> settings, when persistence is used MemoryPolicy always allocates >>>> maxMemory >>>> size for performance reasons. >>>> >>>> As default size of maxMemory is 80% of physical memory it causes OOME >>>> exceptions of 32 bit platforms (either on OS or JVM level) and hurts >>>> performance in setups when multiple Ignite nodes are started on the >>>> same >>>> physical server. >>>> >>>> I suggest to rethink these defaults and switch to other options: >>>> >>>> - Check whether platform is 32 or 64 bits and adapt defaults. In this >>>> case we still need to address the issue with multiple nodes on one >>>> machine >>>> even on 64 bit systems. >>>> >>>> - Lower defaults for maxMemory and allocate, for instance, max(0.3 * >>>> availableMemory, 1Gb). >>>> This option allows us to solve all issues with starting on 32 bit >>>> platforms and reduce instability with multiple nodes on the same >>>> machine. >>>> >>>> >>>> Thoughts and/or other options? >>>> >>>> Thanks, >>>> Sergey. >> >>
