George Schlossnagle Presents talk On High Performance PHP

p. !!

# User a compiler cache
# Control your include trees to no more than 10 includes
# Be mindful of how you use your RDBMS
# Be mindful of how you use other network resources
# Use RegEx cautiously
# Always build with caching in mind
# Output buffering and compression are good.
# Watch for resource exhaustion
# Profile early, profile often.
# Dev-Ops cooperation is essential.

p. George made the point that RDBMS are the most common application bottleneck that he runs across when helping people improve their PHP performance.