It would be interesting to see how jemalloc performs compared to tcmalloc. The article doesn't explain why they choose tcmalloc among other alternative memory allocators.
I've mentioned at the beginning of this article, that we already have several systems running with tcmalloc. So using jemalloc would mean that we would need to bring new dependency. Tcmalloc solves fragmentation issue really well for us, we can get estimation of how much memory is 'lost' due to fragmentation. We saw that potential saving from let's say jemalloc, cannot be higher than 1-3% of memory use and decided it's not worth to bring new dependency for so little value.
At work we've been able to use mimalloc to great effect, using it as a drop-in replacement for the standard msvc allocator showed 3x runtime (!) improvements on multi-minute workloads. In terms of memory use we also saw improvements, but less dramatic.
Of course these numbers mean nothing without context (and there was much more heap allocation going on than needed), but getting that kind of performance improvement for (comparatively) such little effort really changed my view on memory and optimization.
Not the most user-friendly library though, perhaps that is a result of its selling point: 0 code changes needed.