FWIW, I've actually been doing some RTK perf optimizations over inreduxjs/redux-toolkit#4361 (comment) , and found that 1) it was faster to do some reads on aconst ids = current(state.ids) array instead of a wrapped array, 2) the majority of the remaining overhead seems to be in Immer, 3) a lot of it looks like it's infinalizeProperties

See also#1107. There are several ways to make Immer quite a bit faster, but it would required much more loosely treating things that have getters/ non-enumerables / symbolic properties, which would benefit the majority of the user base, but also create enough failure scenarios to flood the issue tracker😅

@mweststrate out of curiosity, how much of a perf difference do you think this will make?

FWIW it looks like onlyone test failed:

FAIL __tests__/base.js  ● Test suite failed to run    TypeError: Cannot perform 'get' on a proxy that has been revoked      2379 | })      2380 |    > 2381 | expect(state[sym].x).toBe(2)           |                   ^      2382 | })      2383 | }      2384 |      at __tests__/base.js:2381:21      at testObjectTypes (__tests__/base.js:2368:2)      at __tests__/base.js:1861:28      at __tests__/base.js:1860:3      at runBaseTest (__tests__/base.js:61:2)      at Object.<anonymous> (__tests__/base.js:32:4)

@Pyaepyae-art please stop randomly approving draft or merged PRs. I'm not sure why you are doing this. I hope it is unintentional. But just in case, on the next contextless review you will be banned from the repo.