MongoDB 3.2.10-rc2 is out and is ready for testing. This is a release candidate containing only fixes since 3.2.9. The next stable release 3.2.10 will be a recommended upgrade for all 3.2 users.
Fixed in this release:
- SERVER-12048 Calling "service mongod start" with mongod running prevents "service mongod stop" from working
- SERVER-16801 Update considers a change in numerical type to be a noop
- SERVER-24885 The systemd MaxTasks feature can prevent mongod from accepting new connections
- SERVER-24971 Excessive memory held by sessions when application threads do evictions
- SERVER-25478 Use wtimeout in sh.setBalancerState
- SERVER-25951 Report additional metrics in getMore slowms logging
- SERVER-25039 Aggregation can attempt to re-plan after collection has been dropped
- SERVER-25478 Use wtimeout in sh.setBalancerState
- TOOLS-1429 mongostat panic when monitored server is restarted
- WT-2026 Maximum pages size at eviction too large
- WT-2924 Ensure we are doing eviction when threads are waiting for it
As always, please let us know of any issues.
-- The MongoDB Team
How Saavn Grew to India’s Largest Music Streaming Service with MongoDB
Building a push notification system on a sophisticated data analytics pipeline powered by Apache Kafka, Storm and MongoDB 2015 was an important year for the music industry. It was the first time digital became the primary revenue source for recorded music, overtaking sales of physical formats. Key to this milestone was the revenue generated by streaming services – growing over 45% in a single year. As with many consumer services, the music streaming market is fragmented across the globe. In India – the 2nd most populous country on the planet and second largest smartphone market – Saavn has grown to become the sub-continent’s largest music service. It has 80m subscribers, experiencing a 9x increase in Daily Active Users (DAU) in just 24 months, with 90% of its streams served to mobile users. There are many factors that collectively have driven Saavn’s growth – but at the heart of it is data. And for this, they rely on MongoDB. !(https://webassets.mongodb.com/_com_assets/cms/Saavn-Logo-Horizontal-White-500-eua0kyb1uk.png) Saavn started out using MongoDB as a persistent cache, replacing an existing memcached layer. They soon realised the versatility and flexibility of the database to serve as the system of record for its data on subscribers, devices, and user activity. It was MongoDB’s flexibility and scalability that proved instrumental to maintain pace with Saavn’s breakneck growth. Through its extensive collection of music, the company quickly attracted new users to its streaming service, but found engagement often dropped away. It identified that push notifications sent directly to client devices was key to reconnecting with users, and keeping them engaged by serving personalized playlists. At this year’s MongoDB World conference, CTO Sriranjan Manjunath, presented how Saavn has used MongoDB as part of a sophisticated analytics pipeline to drive a 3x increase in user engagement. As Sriranjan and his team observed, it wasn’t enough to simply broadcast generic notifications to its users. Instead Saavn needed to craft notifications that provided playlists personalized to each user. Saavn built a sophisticated data processing pipeline that uses a scheduler to extract device, activity and user data stored in MongoDB. From there, it computes relevant playlists by analyzing a user’s listening preferences, activity, device, location and more. It then sends the computed recommendations to a dispatcher process that delivers the playlist to each user’s device and inbox. To refine personalizations, all user activity is ingested back into a Kafka queue where it is processed by Apache Storm and written back to MongoDB. Saavn is also expanding its use of artificial intelligence to better predict users interests, and is using MongoDB to store the resultant machine learning models and serve them in real time to the recommender application. The system currently sends 30m notifications per day, but has been sized to support up to 1m per minute, providing plenty of headroom to support Saavn’s continued growth. In his presentation, Sriranjan discussed how Saavn migrated from MongoDB 2.6 to MongoDB 3.0, taking advantage of the WiredTiger storage engine’s document level concurrency control to deliver improved performance. He talks about his key learnings in modifying schema design to reflect the differences in how updates are handled by the underlying storage engine, and usage of TTL indexes to automatically expire data from MongoDB . Sriranjan also discusses shard key selection to optimize uniform data distribution across the cluster, and the benefits of using MongoDB Cloud Manager for system monitoring and continuous backups, including integration with Slack for automated alerting to the ops team. Click through to view Saavn’s presentation from MongoDB World To learn more about managing real time streaming data, download: The MongoDB and Kafka white paper About the author - Mat Keep Mat is a director within the MongoDB product marketing team, responsible for building the vision, positioning and content for MongoDB’s products and services, including the analysis of market trends and customer requirements. Prior to MongoDB, Mat was director of product management at Oracle Corp. with responsibility for the MySQL database in web, telecoms, cloud and big data workloads. This followed a series of sales, business development and analyst / programmer positions with both technology vendors and end-user companies.
10 Things (You'll Love) About MongoDB.live
Over the course of a year, the coronavirus pandemic has left a lasting impact on every aspect of the tech space — including applications, data, business models, and much more. To help developers build new skills and adapt to this new landscape, MongoDB.live will include keynotes, workshops, breakout sessions, and Q&A panels on the present and future of data. MongoDB.live will run from July 13-14, and will have something for everyone — whether you’re a seasoned DevOps engineer or a new database administrator. Here are ten things to look forward to at MongoDB.live: Learn a new skill — whether it’s an unfamiliar topic that piques your curiosity, or a subject you’ve always wanted to know more about. With countless workshops and talks spread across 9 tracks, from Security and Operations to Backend Development, there’s something to address all interests and abilities. Hone your soft skills too — in case you’re up for a promotion or have your eye on moving into management. You’ll learn how to empower direct reports, build inclusive teams, streamline inefficient processes and workflows, and much more. Be the first to get the scoop on MongoDB product releases. See what’s new in MongoDB 5.0 and Atlas — and sign up to preview and beta test the latest features. Drop in on a partner talk to see how MongoDB interfaces with other companies and technologies. Learn how to use different drivers, platforms, libraries, or languages in tandem with MongoDB. Dive into the Internet of Things (IoT). Learn to build a complex, multi-cloud IoT project using MongoDB and PeerIslands, see how Bosch.IO used MongoDB to revolutionize automotive IoT and quality assurance testing, or examine the ethical dilemmas of IoT design. Make the most of the MongoDB application data platform. Learn to monitor performance on Realm Sync, optimize data flow with Atlas Data Lake, and validate schema in MongoDB to prevent data inconsistency. Rethink everything you know about data and development. Attend talks on reimagining the way coding is taught, see how Rent the Runway uses MongoDB Atlas to help automate its warehouse operations, and experience the (r)evolutionary new capabilities of MongoDB 5.0. Follow along with step-by-step tutorials for everything from mastering the use of the MongoDB command line to securing your cloud-native applications. Check out exciting new stacks and development frameworks, including FARM (FastAPI, React, and MongoDB), JAMStack with MongoDB, and more. Speed up innovation, reduce risk, and build better applications. See how other companies are using MongoDB to stream live data, sequence the coronavirus, or migrate to the cloud. Listen to talks from organizations like HSBC, Porsche, Shutterfly, and Oxford Nanopore, see interesting projects, and pick up some inspiration for yourself. This is just a small sample of what to expect at MongoDB.live. This free, virtual event will be bursting with plenty of other activities, including networking opportunities, interactive Q&A panels, games, and much more. Register today to reserve your seat. We can’t wait to see you there!