tek12: graphing real-time performance with graphite

 Graphing real-time performance with

GraphiteNeal Anders - https://joind.in/650

whoami

Neal AndersSenior Software Engineer at Infobloxhttp://github.com/nanderoohttp://neal-anders.com@nanderoo

shameless plug

Infoblox is working on some cool stuff...- DNS, DHCP, IPAM, NCCM- IPv6 Center of Excellence- IF-Map / DNSSec- Hiring (sales, services, support, engineering)

disclaimer

These thoughts and opinions are my own, and not of my employer, bla bla bla...

whois $USER

Quick poll:- Designers- Developers- Sys-Admins- Networking- Management- Other...?

overview

What will we cover:- What is Graphite?- What data to capture- Chart interpretation

but why

I worked at a place with major scale fail- boxed vs service- 100's of servers in multiple datacenters- manual processes, shell scripts- no insight into the app, infrastructure- n-tier architecture- on-call duties- needed therapy, got it, didn't help 

what is graphite

- Scalable real-time graphing system- 3 main components: - Web front-end, graphite - Processing backend, carbon - Database, whisper- Python based* 

* It's good to learn other languages

what is graphite

Setup / Documentation:- Easy to setup- Decent documentation- API and CLI access

what is graphite

What does it capture?- Numeric time-series data...  point some.data.path 

value 3.2 

timestamp 1337690041 (epoch)

what is graphite

How much data?- configurable- precision - retention period- aggregation  

what is graphite

what is graphite

Notes / gotchas:- Scales horizontally- Heavy on disk-io- Fault tolerance- Data loss- Precision or Storage Space / io

what data to capture

...so what information should we capture? ..how detailed do we get? ..and does it have historical relevance? ..are just a few key metrics enough? 

what data to capture

what data to capture

Thoughts on maximum vs. minimum:- What information do you need to capture?- Application Data (yes!)- System Data: cpu, disk-io, mem usage- Network: Connections? Latency? Packet loss?- Fine-grained vs summary and aggregate?

what data to capture

In your app:- function / method / calculation time- template / content generation- database query execution- Internal and 3rd-party API calls- queue sizes, processing times- A/B testing?

what data to capture

From the systems:- cpu- disk usage- io (disk, network interface)- memory / paging / swap- file handles- log entries

what data to capture

At the network level:- connection count- socket state- qos levels- firewall stats- cdn / cache response- 3rd party status

chart interpretation

...it's like reading tea leaves... ...domains of knowledge leave gaps... ...thats not my job... ...forest through the trees...

chart interpretation

So what are we looking for:- normality *- deviations- jitters- historical performance- double rainbows * not present per Cal's keynote

chart interpretation

Because at 3am when you get paged... Wouldn't it be great to correlate the site going down... due to swapping... because of high memory usage... thanks to that code that got pushed... that had that change to how you processed row results from a large database query.

chart interpretation

Or that change window that just happened... Where the security folks made some config changes to one of the firewalls.. that is now blocking your outbound API calls.. just from some app servers in one of the datacenters..

chart interpretation

What about that new kernel that fixes a memory leak... Can you compare side by side, and with historical context, what that looks like?  What about a physical machine vs a virtual one?

chart interpretation

Do we need to retune our load-balancers, app servers, or database replication? Does higher site traffic over the past few weeks show signs of strain? Did that cache layer we add help any? Is historical data choking once-fast pages?

demo

wordpress example

some final thoughts

- come full circle, stats back in- this is one solution, there are others (statsd)- part of a larger tool bag- implement before big changes- establish a reference / baseline- suitable for dev, qa, and production- make implementing data capture easy

resources

http://graphite.wikidot.comhttp://wordpress.orghttp://memgenerator.nethttp://www.flickr.com/groups/webopsviz/ ..more resources available online..  

feedback

joind.in - https://joind.in/6502email - neal.anders@yahoo.com 

fin

Thank you.

Bonus

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