Getting the most from a constrained environment.
THE PRINCIPLE
Serve as many requests as possible without running application code.
PAGE CACHING
The largest single gain. A cached page is served from a file without touching PHP or the database.
Exclude anything visitor-specific.
A CDN
Static files served from elsewhere, removing that load from your account entirely. Also absorbs traffic spikes and attack traffic.
For a busy site this is the most effective single addition.
REDUCING WORK PER REQUEST
Fewer queries, less memory, no external API calls during page load.
BLOCKING WHAT SHOULD NOT BE THERE
Bot traffic frequently makes up a large share of requests. Identify it in the access log and block or challenge it.
BACKGROUND WORK
Move anything slow out of the request cycle into a queue processed by cron.
WHEN YOU HAVE GENUINELY OUTGROWN IT
Consistent resource limits after all of the above, with legitimate traffic. Then a larger plan or a VPS is warranted.
Open a ticket with your usage graphs and we will advise honestly.
