NUMA (Non Uniform Memory Access) for MongoDB
We usually did see some performance boost when NUMA was disabled using -> numactl –interleave=all ….. Below are the details from MongoDB http://docs.mongodb.org/manual/administration/production-notes/ Running MongoDB on a system with Non-Uniform Access Memory (NUMA) can cause a number of operational problems,…
MongoDB Queries
–> To find documents in a collection we have syntax db.<collection Name>.find(); –> db.books.find(); — it will provide all documents in collection books. It actually returns a cursor. –> To make the output look a bit pretty we have following…
MongoDB Authentication
[root@my-host-name bin]$ cat /etc/mongod.conf # MongoDB Configuration File # # General Settings journal = true fork = true quiet = true directoryperdb = true smallfiles = true # Logging verbose = true logappend = true oplogSize = 50 #logpath =…
MongoDB: Change opLog Size
What is opLog ? Just as Transaction Log in MS SQL Server or Binary log in MySQL, all those transactions on MongoDB RS will be written into a separate file, called opLog. This opLog will have a fixed size, which…
MongoDB Diagnostic Tools/Utilities
MongoDb Inc. currently don’t have one-tool-for-any-troubleshooting-scenario. However, they have a number of tools that help with different aspects of trouble shooting. The best practice is (like in many other Monitoring/Troubleshooting apps) to have a holistic (NOC) view on overall system…
MongoDB Export cmd
Here’s is a simple MongoDB ‘mongoexport’ command syntax to backup the document/database. This command can be used to backup based on particular conditions (‘where’ clause) Go to MongoDB bin directory and execute as below:./mongoexport –host localhost –port 10000 -d doc_name…
MongoDB vs MySQL
Here is a comparison between MongoDB and Relational database, MySQL: Because of distributed key value store, MapReduce calculation capability and document oriented NoSQL features, MongoDB® is The database for Big Data processing.
[MongoDB]: Clients
While mongo shell provides an excellent non-GUI way to interoperate with the data, there are many GUI tools available to view/modify MongoDB data and also to provide support for administrative tasks in a more graphical manner. Best place to start…
[MongoDB]: How do we create indexes
Let’s say you have a query which takes around 120 ms to execute without indexes i can assure you that with proper indexes you can reduce that time by at least 10 times in MongoDB. Let me show you with…
How do I start MongoDB
If MongoDB installed successfully through RPM installation/any other process, you’ll usually see the below Mongo binaries in the bin (eg. */opt/mongodb/bin*) folder which will be useful to start the Mongo processes (mongod&mongos). [user@hostname bin]$ pwd /opt/mongodb/bin [user@hostname bin]$ ls -lthr…