alt Hacker News> A month ago, I went on a performance quest trying to optimize a PHP script that took 5 days to run. Together with the help of many talented developers, I eventually got it to run in under 30 seconds
That's a huge improvement! How much was low hanging fruit unrelated to the PHP interpreter itself, out of curiosity? (E.g. parallelism, faster SQL queries etc)
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In general, it is bad practice to touch transaction datasets in php script space. Like all foot-guns it leads to Read-modify-write bugs eventually.
Depending on the SQL engine, there are many PHP Cursor optimizations that save moving around large chunks of data.
Clean cached PHP can be fast for REST transactional data parsing, but it is also often used as a bodge language by amateurs. PHP is not slow by default or meant to run persistently (low memory use is nice), but it still gets a lot of justified criticism.
Erlang and Elixir are much better for clients/host budgets, but less intuitive than PHP =3
Almost all, actually. I wrote about it here: https://stitcher.io/blog/11-million-rows-in-seconds
A couple of things I did:
- Cursor based pagination - Combining insert statements - Using database transactions to prevent fsync calls - Moving calculations from the database to PHP - Avoiding serialization where possible