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Stop Tilting at Windmills: Spotting Bottlenecks
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Presented by Yann Malet & Brandon Konkle
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Get numbers before you start trying to debug. You can't fix a problem you don't have.

Performance Testing
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* Time to load a page
* Number of queries per page
* Time taken by the queries
* Number of cache hits/misses
* Time spent waiting on 3rd parties

.. note:: Django Debug Logging: https://github.com/lincolnloop/django-debug-logging

Load Testing
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* Taking your entire app infrastructure into account
* Understanding how your performance changes under stress and over time
* Creating realisting test plans that imitate real life traffic

Database
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* Handling numerous queries in parallel
* Types of queries running at the same time

Caching
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* Cache key expiration
* Cache size and key eviction

.. note:: JMeter


Command-line tools
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* htop
* dstat
* pg_top, mtop
* memcache-top