MongoDB 2.2.0 Released

My experience with MongoDB hasn't been the most pleasant in a write-heavy environment. Until they fix the write lock properly, MongoDB is pretty much useless for many high throughput applications in my opinion...<p>The new DB level locking introduced in this release is a joke. There's not much difference between that and the old global write lock unless you split your database in dozens of smaller ones. What a pain. I wish they'd just stop pretending and addressed the issue properly once and for all.<p>I really want to like and use MongoDB because the way data is represented and how it can be queried is awesome.

Awesome release,<p>notes summary:<p>• Aggregation Framework to fix some map-reduce woes.<p>• TTL Collections<p>• DB Level Locking (A step in the right direction)<p>• Better yielding on page faults<p>• Tag aware sharding (HELL YES)<p>• Better Read Prefs<p>• Indexes now handled by mongodump/mongorestore<p>• mongooplog replay is awesome for getting point in time backups<p>• Shell now has full unicode, multiline command history, $EDITOR support (all from change to linenoise.c

I've been playing around with the Aggregation Framework lately (using the release candidate). The performance seems to be pretty reasonable, especially when compared to similar tasks with the old MR framework. A quick and dirty benchmark number in case anyone is interested:<p>* Obligatory unscientific, probably not meaningful, etc. disclaimer.<p><i>Mongo Version:</i> 2.2.0-rc1<p><i>Hardware:</i> MBP, Snow Leapord, 2.2 GHz Intel Core i7, 8 GB mem<p><i>Data:</i> Single collection with 500k records (machine generated time-series event data)<p><i>Query Pipeline:</i><p><pre><code> [ { $match: { ts: { $gte: 1293858000000, $lt: 1296536400000 } } }, { $group: { _id: 'aggregations', sum: { $sum: '$foo' }, num: { $sum: 1 }, avg: { $avg: '$bar' } } } ] </code></pre> <i>Results:</i> The time range matched against above matches 42,466 documents within the collection. The average response time over 50 runs is 419ms. Not exactly "Big Data OLAP" stuff just yet, but plenty fast enough for most use cases involving reasonably small sets of data. Great job to the MongoDB team!

Release notes: <a href="http://docs.mongodb.org/manual/release-notes/2.2/" rel="nofollow">http://docs.mongodb.org/manual/release-notes/2.2/</a>

For startup projects I love Mongo because we can get a product up and running very quickly. However I always feared in the back of my head we would have to move off of it if our service got too big. Maybe it is all the complaints from a small portion of heavy users. Regardless, big updates like this are going a long way to help make me feel content on continuing to use it as we grow.

In all this talk of locking were missing the real benefit to a heavy write environment, better yielding. this is going to be huge for those one off writes that in the past would have held the lock. Also I am looking forwards to playing with the new aggregation framework.

There is one thing holding me back still from mongo or I'd be using it right now instead of Postgres: native decimal support [1].<p>There are a lot of proposed work arounds, and some surely work fine if you're only dealing with 2 decimal currency.<p>The solutions don't scale for arbitrary precision based on the field.<p>The new aggregation framework is a fantastic step forward and from my testing is relatively peppy, even at a 150k document collection.<p>Side note: Anyone know a nosql solution that doesn't treat decimals as floats?<p>[1] <a href="https://jira.mongodb.org/browse/SERVER-1393" rel="nofollow">https://jira.mongodb.org/browse/SERVER-1393</a>

The Aggregation Framework is a great feature, already in production...

Does anyone know if Collection level locking is in the pipeline?

Great news. We use MongoDB for call data collection, distributed control, and as a firmware/application fileserver in for telecoms testing.

The true secret to Mongo's awesomeness for me has always been the dev experience. JSON documents, query by example, etc.: Awesome API.

A friend of mine wrote this a few months back:<p><a href="http://blog.engineering.kiip.me/post/20988881092/a-year-with-mongodb" rel="nofollow">http://blog.engineering.kiip.me/post/20988881092/a-year-with...</a><p>Almost all of it is still valid. "To be fair, the global write lock is now JUST a DB level write lock. Living in the future guys."

Blog post with the details is up <a href="http://blog.mongodb.org/post/30451575525/mongodb-2-2-released" rel="nofollow">http://blog.mongodb.org/post/30451575525/mongodb-2-2-release...</a>

Still no support for Solaris on SPARC! :(

Awesome! Looking forward to seeing this propagate through the 10gen official repos like yum.

Have had a great experience with MongoDB

I can't wait upgrade.

Interesting