Since our initial release last summer, TokuMX has supported fully ACID and MVCC multi-statement transactions. I’d like to take this post to explain exactly what we’ve done and what features are now available to the user.

But before beginning, an important note: we have implemented this for non-sharded clusters only. We do not support distributed transactions across different shards.

At a high level, what have we done?

We have taken MongoDB’s basic transactional behavior, and extended it. MongoDB is transactional with respect to one, and only one, document. MongoDB guarantees single document atomicity. Journaling provides durability for that document. The database …

The upcoming Percona Live London conference, November 11-12, features quite a number of talks about the latest MySQL features and related technologies. There will be a lots of talks about the new MySQL 5.6 features:

• Opening keynote highlights MySQL 5.6 new features.
• New InnoDB Compression talk will cover the new compression algorithm, implemented by Facebook and included in MySQL 5.6.
• New  …

We already discussed one to one relations in MongoDB, and the main conclusion was that you should design your collections according to the most frequent access pattern. With one to many relations, this is still valid, but other factors may come into play.

Let’s look at a simple problem: we are a shop and we want to store customers’ information as well as their orders. Each customer can make several orders, this is a one to many relation. With MySQL or any relational database system, we would create 2 tables:

CREATE TABLE customer (
  customer_id int(11) NOT NULL AUTO_INCREMENT,
  name varchar(50) NOT NULL DEFAULT '',
  zipcode varchar(10) DEFAULT NULL,
  PRIMARY KEY (customer_id)
) ENGINE=InnoDB;
CREATE TABLE orders (
  order_id int(11) NOT NULL AUTO_INCREMENT,
  customer_id int(11) NOT NULL DEFAULT '0', …

Since introducing TokuMX, we’ve discussed benefits that TokuMX has for existing MongoDB applications that require no changes. In this post, I introduce an extension we’ve made to the indexing API: clustering indexes, a tool that can tremendously improve query performance. If I were to speak to someone about clustering indexes, I think the conversation could go something like this…

What is a Clustering Index?

A clustering index is an index that stores the entire document, not just the defined key.

A common example is …

October 1, 2013 By Severalnines

Database vendors regularly issue critical patch updates to address software bugs or known vulnerabilities, but for a variety of reasons, organizations are often unable to install them in a timely manner, if at all. Evidence suggests that companies are actually getting worse at patching databases, with an increased number violating compliance standards and governance policies1.

Patching that require database downtime would be of extreme concern in a 24*7 environment, however most cluster upgrades can be performed online. ClusterControl performs a rolling upgrade of the cluster, upgrading and restarting one node at a time. The logical upgrade steps might slightly differ between the different cluster types. 

Upgrading your Database

In this post, …

I had to laugh (just a bit) at this on the exhibitor floor at Oracle Open World 2013. There was a large MongoDB presence at the Slot 301. There are a few reasons.
First, the identity crisis remains. There is no MongoDB in the list of exhibitors, it’s 10gen, but where is the 10gen representation in the sign. 99.99% of attendees would not know this.
Second, the first and only slide I saw (as shown below), tries to directly compare implementing a solution to Oracle. The speaker made some comment but I really zoned out quickly. Having worked with MongoDB, even on one of my own projects, contemplated the ROI of being proficient in this for consulting, even discussing at length with the CEO and CTO, and hearing only issues with MongoDB with existing MySQL clients, I have come to the conclusion that MongoDB is a niche product. It’s …

September 24, 2013 By Severalnines

For those of you who know Severalnines and maybe use some of our tools & products, you’ll know that we provide our users with a monthly summary of all the resources & tools that we’re publishing. Since this is publicly available material, we thought it’d be useful also for the broader open source database community.

In the past month, we’ve made the following resources & tools available: 

• Troubleshooting MySQL Cluster (free online MySQL Cluster Training)
• Zero Downtime Data Center Migration with Galera
• ClusterControl 1.2.3 Released
• High Availability OpenStack - Clustering the Database Backend
• NoSQL Battle of the East Coast - Benchmarking MongoDB vs TokuMX Cluster
• Full restore of a Galera Cluster from Backup

  …

In talking to existing MongoDB users and TokuMX evaluators, I’ve often heard that the performance of MongoDB is very good as long as your working data set fits in RAM. The story continues that if your working data set grows to be larger than the RAM on your server, the built-in sharding capabilities of MongoDB allow you to scale horizontally.

As my benchmarking presentation at Percona Live 2013 pointed out, I’m never one to accept something without at least running it once myself. I decided to run my Sysbench for MongoDB benchmark on an in-memory workload, meaning that all of the data fits …

We’ve been hard at work on TokuMX since it’s initial release just over 2 months ago. Today we released TokuMX v1.2 which includes Hot Backup in the Enterprise Edition.

Hot Backup allows users to create a backup of a running TokuMX primary or secondary server in a replica set, with no blocking of writes for clients. We will be blogging more about the Hot Backup technology in the coming weeks. This same technology is used for Hot Backup in TokuDB.

Also worth noting are the features we’ve added since the initial TokuMX release:

• Migration Tools. Migrate to TokuMX from MongoDB using our tool that replays MongoDB repication. This allows a TokuMX server to stay in sync with a MongoDB replica set, reducing downtime for production go-live.
• Bulk Loading. Significantly improves data load speeds …

UPDATE 2013-08-30: Tungsten 2.1.2 was released.

UPDATE 2013-08-23: We have found a few problems that happen when replicating with RBR and temporal columns. We will have to publish an updated bugfix release quite soon.

Tungsten Replicator 2.1.1 is out. Key features in this release are:

• A better installer, of which we have already given a preview in tpm, the multi-master composer. The new installer allows faster and more powerful deployments of both single and multiple masters topologies. And it also allows the next feature:
• Secured communication layer. Now the replicator data and administrative …