Have you considered writing your own string matcher for the simple cases like fixed patterns?
I got some pretty solid wins just by guarding some regex executions with simple strings.indexof calls.
I got some pretty solid wins just by guarding some regex executions with simple strings.indexof calls.
It's C, but openbsd grep does something like this because libc regex is super slow. Look for fastcomp on https://github.com/openbsd/src/blob/master/usr.bin/grep/util... It's not super sophisticated, but enough to beat the full regex engine.
In the go code where I did this, it was a little different, with a static pattern. Something like "(\w+) apple" to find all apple adjectives or whatever, but the regexp wasted so much time matching words before not apples. A quick scan for "apple" to eliminate impossible matches made it faster. This depends more on knowing regex and corpus, so probably less relevant for awk.
[1]: https://lists.freebsd.org/pipermail/freebsd-current/2010-Aug...
It's been a while since I've looked at the source code, but it is almost certainly already doing basic prefix literal optimizations.
The more advanced literal optimizations come into play when every match must start with one of a few possible characters or strings. Then you get into things like Aho-Corasick or fancy SIMD algorithms (Teddy).