Engineer, 10gen

Mark Hillick - @markofu

#mongosv

Using the MongoDB Monitoring Service (MMS)

What, where, numbers?

What is MMS?

• MongoDB monitoring Saas solution with:

– Per minute granularity

– Alerting: host up / down, metrics etc

– Event tracking (server restart, step down, …)

• Host management (auto discover)

• Profiling

• Hardware stats also

Why use MMS? (1)

• Overview – Bird’s Eye

– Macro

• Drill down (minute by minute)

– Micro

Why use MMS? (2)

• Haz all teh things

• Tailored specifically for MongoDB

• Incredibly helpful for 10gen Support when troubleshooting

A few numbers …

• Monitors over 19k database servers

• 40k writes per second

• 400 metrics per ping packet

• 9 billion metrics recorded per day

How?

Set up MMS – it’s easy

• Go to http://mms.10gen.com

– Create a new account or sign in with jira user.

– Pick an explicit company name

– Download and run the agent

– From MMS dashboard, add a host to monitor

The MMS client (agent)

• Small Python app

• A single agent process

– Failover – multiple agents

• Connect to mms.10gen.com (SSL over TCP 443)

Host

Operational Stats

Alerting

Alerts - Config

All good

Alerts - Closed

Events

Security

Security

• Purely stats (metadata). – Log transfer has to be turned on.

• HTTPS & connections are outbound only (from the agent)

• If profiling in db & MMS, then profiling data is sent

On-premise MMS

• Locally Hosted in Customer Infrastructure

• PCI, HIPAA etc

• Enterprise Customers (2.4)

Measure me!!!

Metrics

• Source : http://www.kaushik.net/avinash/wp-content/uploads/2007/10/metrics.jpg

opcounters• Count of every operation per second

• getMore – each batch of a query

memory• Mapped: sum of files on disk

• Virtual memory: 2 x mapped (j) + process overhead

• Resident memory: data in RAM actively used

Lock %• Amount of time spent in the write lock

• From 2.2 : each db has own lock

Background flush• Flush every 60 seconds

• Watch: if flush time gets close to sync delay

Page faults• Disk IO

• Readahead

Replication• On primary: amount of time in oplog

• On secondary: replication delay to primary

Metrics that we discussed• Opcounters

• Lock %

• Background Flush

• Page Faults

• Replication

Metrics for performance

• Resident memory: how much data in RAM?

• Page Faults: paging to disk? Readahead?

• Journal commits in write lock: separate journal

• High background flush: reduce sync delay to smooth

Documentation

Docs? Where?

• Manual : https://mms.10gen.com/help/

– Web– PDF

• FAQ : https://mms.10gen.com/docs/faq

• Blah

Futures

Feature Request

• JIRA Ticket - MMSSUPPORT

Coming up…

• Data visualization, e.g. shard distribution (Q1 2013)???

• Move from Python to Java

• Blah – Ryan???

Conclusion

Conclusion

• Easy to use

• Macro & micro

• Detailed monitoring features

• Aides 10gen Support immensely

Engineer, 10gen

Mark Hillick - @markofu

#mongosv

Questions?