Issue
For more than a month is my war with mongoDB. Until I lose =] ...
Battle 1. Battle 2. And now a new problem. Again, not enough memory.
Initially, this was solved by simply increasing the memory at a rate of VPS. Then journal = false. But now I got to the top of your plan and continue to increase the memory is not possible.
For my base are lacking 4 GB of memory. How should I choose a database for the project, was nowhere written that there are so many mongoDB memory. With about 10 million records in the mongoDB missing 4 GB of memory, when my MySQL database with 10 million easily copes with 1.4 GB of memory.
The problem as I understand it, a large number of index fields. But since I can not log into the database, respectively, can not remove them. They needed me in the early stages of development, now they are not important to me.
Tell me please, can I remove them somehow? There is a dump of the database is completely whole folder database / data / db On my PC with 4 GB of memory database does not start on a VPS with 4GB same. As an alternative, I think to take a test period at some VPS / VDS to run mongo and delete keys.
Do you know a web hosting with a test period and 6 GB of memory?
Or if there is an alternative, could you say what?
Solution
The issues has very little to do with the size of your data set. MongoDB uses memory mapped files for its storage engine. As such it'll start swapping in pages of hot data into memory when it can and it does so fairly aggressively (or more accurately, the OS memory management does).
Basically it uses as much memory as is available to it and there's very little you can do to avoid it. All data pages (be it actual data or indexes) that are accessed during operation will be swapped into memory if there is space available.
There are plenty of references to this on the internet and on mongodb.org by the way. Saying it isn't mentioned anywhere isn't really true.
Answered By - Remon van Vliet