How MongoDB Works

Deck for a short talk I've given on a EPAM Software Engineering Conference 2013.

Transcript

1. How MongoDB works Uladzimir Mihura Senior Software Engineer, EPAM Systems Software Engineering Conference 2013
2. Data Model {name:'mongo',  type:'DB'}
3. Data Model: Document oriented {    _id:  1,    name:  {        first:  'Michael',        last:  'Faraday'    },    birth:  new  Date('Sep  22,  1791'),    death:  new  Date('Aug  25,  1867'),    contribs:  ['Chemistry',  'Electricity',  'Diamagnetism'] }
4. {  hello:  'SEC  2013'} \x19\x00\x00\x00  \x02hello \x09\x00\x00\x00  SEC  2013\x00 Data Model: BSON
5. Data Model: Structure Document Collection Database MongoDB Instance
6. db.foo.find({name:'Niels',  surname:'Bohr'}) Reading
7. • find, findOne • accepts a conditions object • regex, strings, numbers, etc... • rich operators • $lt, $gt, $or, $and, $in, $ne, ... • projections • specify fields to return Reading: Dynamic Queries
8. Reading: Indexes • B-Tree • multiply fields • options • unique • sparse • 2d • full text search (≥2.4) Di Lu Rh B C Cr Zo St Sa Ka H F B C Cr
9. Reading: Query Optimizer x x remember db.foo.find({  x:  10,  y:'bar'}) index on y index on x full scan
10. Writing db.foo.insert({name:'Georg',  surname:'Ohm'})
11. • Errors ignored (even network errors) • Unacknowledged (fire & forget) • Acknowledged (write accepted) • Journaled • Propagated to the replica set members Writing: Write Concerns
12. Writing: Isolation db.foo.update(   {  field1  :  1  ,  $isolated  :  1  },   {  $inc  :  {  field2  :  1  }  }  , {  multi:  true  }   )
13. Storage Management {name:'mongo',  type:'DB'}
14. Storage: Padding factor ... Padding Header BSON Data Padding Header ...
15. Storage: Directory Layout -­‐rw-­‐-­‐-­‐-­‐-­‐-­‐-­‐    1  trnl    trnl        64M  Jan  28  14:38  foo.0 -­‐rw-­‐-­‐-­‐-­‐-­‐-­‐-­‐    1  trnl    trnl      128M  Jan  28  14:26  foo.1 -­‐rw-­‐-­‐-­‐-­‐-­‐-­‐-­‐    1  trnl    trnl      256M  Jan  28  14:31  foo.2 -­‐rw-­‐-­‐-­‐-­‐-­‐-­‐-­‐    1  trnl    trnl      512M  Jan  28  14:38  foo.3 -­‐rw-­‐-­‐-­‐-­‐-­‐-­‐-­‐    1  trnl    trnl      1.0G  Jan  28  14:38  foo.4 -­‐rw-­‐-­‐-­‐-­‐-­‐-­‐-­‐    1  trnl    trnl      2.0G  Jan  28  14:38  foo.5 -­‐rw-­‐-­‐-­‐-­‐-­‐-­‐-­‐    1  trnl    trnl        16M  Jan  28  14:38  foo.ns • Separate files per database • Aggressive preallocation
16. Storage: Memory mapped files foo.1 foo.2 foo.3 ... foo.n Virtual Memory
17. Scaling {name:'mongo',  type:'DB'}
18. Scaling: Replication Node 3 Primary Node 1 Secondary Node 2 Secondary Replication Replication client read read read write
19. Scaling: Replication Node 3 Primary Node 1 Primary Node 2 Secondary Replication client read read write
20. Scaling: Replication Node 3 Secondary Node 1 Primary Node 2 Secondary Replication client read read write read Replication
21. Scaling: Sharding Client mongos mongos ... mongod mongod mongod Replica Set mongod mongod mongod Replica Set mongod mongod mongod Replica Set Shards mongod mongod mongod Config Servers
22. MongoDB Drivers Team @ 10gen
23. • MongoLab.com • MongoHQ.com • HostedMongo.com • MongoMachine.com • ObjectRocket • etc Hosted Solutions
24. Thank you. Let’s ask. http://try.mongodb.org/ http://on.fb.me/bymongo/