MongoDB 2.2 At the Silicon Valley MongoDB User Group

Transcript

1. 1
   Ben Becker,
   Software Engineer, 10gen
   ben.becker@10gen.com
   

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2. 2
   2.2
   Aug ‘12
   2.0
   Sept ‘11
   1.8
   March ‘11
   Journaling
   Sharding and Replica
   set enhancements
   Spherical geo search
   Index enhancements
   to improve size and
   performance
   Authentication with
   sharded clusters
   Replica Set
   Enhancements
   Concurrency
   improvements
   Aggregation
   Framework
   Multi-Data Center
   Deployments
   Improved
   Performance and
   Concurrency
   

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3. 3
   2.2 - rc0 released on 7/19
   2.2 - rc1 released today!
   2.2 - out soon!
   

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4. 4
   • Concurrency improvements
   – DB Level Locking
   – More yielding
   • Aggregation Framework
   • Tag aware sharding or geo-sharding
   • Read Preferences
   • TTL Collections
   • Shell enhancements
   • More…
   

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5. 5
   • DB Level Locking
   – Write operations lock at db level, not globally
   • Replication can happen in parallel to write (client db vs. local)
   – Global lock for journaling, fsync etc. only
   – db.serverStatus() enhanced to show lock stats per db
   • Yielding on page fault
   – Started with 2.0
   – Avoid holding write lock on disk access for updates also
   – Stats available as part of db.serverStatus()
   • db.serverStatus().recordStats
   • db.serverStatus().extra_info
   

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6. 6
   • Replaces most common uses of map/reduce
   • Implemented in C++. Hence better performance than
   interpreted JavaScript
   • Operators can be chained similar to Unix pipes
   • Framework allows easy implementation of new
   operators
   • Pipeline and compute operators : $project, $unwind
   $group, $sort, $skip, $add, string functions
   • Use $match and $sort early in the pipeline. Query
   optimizer can use indexes
   

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7. 7
   • Operators
   – $project – specified fields, compute values etc.
   – $unwind – stream arrays
   – $group – aggregate on key
   • Document with tags (array of strings). E.g.
   db.posts.aggregate(
   {$unwind : "$tags"} ,
   {$group : {_id : "$tags", total :{$sum : 1}}})
   • Doc -
   http://docs.mongodb.org/manual/applications/aggr
   egation/
   

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8. 8
   • Most common use -
   • Implemented as generic tags on shard members
   – geographically locate data
   – distribute based on usage
   • Add tags to shards
   – sh.addShardTag( "shard0000" , "a" )
   • Specify range by tag
   – sh.addTagRange( "test.foo" , { _id : -1 } , { _id : 1000 } , "a" )
   • More info
   – https://github.com/mongodb/mongo/blob/master/jstests/
   slowNightly/balance_tags1.js
   

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10. 10
    • Consistent nomenclature across drivers and mongos
    • Modes
    – Primary (default), Primary_Preferred, Secondary,
    Secondary_Preferred, Nearest
    • Replica set tags
    – Read support for replica set tags
    

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11. 11
    • Auto expire data by setting a TTL
    • Use field in document to specify expiry.
    – db.log.events.ensureIndex({“expiryDate": 1}, {expireAfterSeconds: 3600})
    • Dedicated mongod thread regularly removes
    • Can be used with replication and sharding
    • Constraints
    – Should have a date type value
    – Cannot be compound
    – Cannot be used on capped collection
    

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12. 12
    • Verbose mode
    – Shows number of documents affected, time taken
    > db.foo.update({},{$set:{newfield:10}},false,true)
    > set verbose true
    set verbose to true
    > db.foo.update({},{$set:{newfield:10}},false,true)
    Updated 2 existing record(s) in 2ms
    • slaveOk – Settings similar to drivers
    – Greater control from shell or scripts
    – > db.getMongo().setSlaveOk()
    – > db.setSlaveOk()
    – > db.foo.setSlaveOk()
    • Enhanced editing features
    

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13. 13
    • Replication
    – replsetSyncFrom – specify who to sync from
    • Tools
    – mongooplog – tool for replaying oplog
    – Authentication support and concurrency statistics in
    mongotop and mongostat
    • Query optimizer
    – Many improvements not directly visible to user
    – Better support for $in + sort + limit
    • Map/reduce
    – Choose initial split points for sharded output
    

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15. 15
    • Download
    – http://www.mongodb.org/downloads
    • Release notes
    – http://docs.mongodb.org/manual/release-notes/2.2
    • Resolved issues
    – https://jira.mongodb.org/secure/IssueNavigator.jspa?mod
    e=hide&requestId=10907
    • Backward breaking changes
    – https://jira.mongodb.org/secure/IssueNavigator.jspa?requ
    estId=11225
    

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16. 16
    • Standard incremental update. Hence a drop in
    replacement
    • Standalone – Shutdown and replace
    • Replica Set – Rolling upgrade starting with
    secondaries
    • Sharded Cluster – Mongos, Config servers and then
    rolling upgrade of shards
    • More details at
    http://docs.mongodb.org/manual/release-
    notes/2.2/#upgrading
    

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18. 18
    • Operational enhancements
    – Integration with external authentication systems
    – Simplified sharding setup
    – Further reductions in fragmentation
    • New features
    – Built in full-text search
    • Performance improvements
    – Further concurrency improvements
    – Improved aggregation framework performance
    – More efficient usage of indexes, including multiple indexes
    on a single query
    

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19. 19
    @mongodb
    conferences, appearances, and meetups
    http://www.10gen.com/events
    http://bit.ly/mongofb
    Facebook | Twitter | LinkedIn
    http://linkd.in/joinmongo
    download at mongodb.org
    We’re Hiring !
    ben.becker@10gen.com
    

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