We noticed in ScyllaDB that performance suffers due to high icache miss
rate; we saw a very low IPC.
We implemented a SEDA-like mechanism to run tasks tied to the same
function sequentially; the first task warms up icache and the branch
predictors, the second and further runs benefit from this warmup.
The implementation of the mechanism in seastar can be viewed here:
https://github.com/scylladb/seastar/commit/384c81ba7227a9a99d485d1bb68c98c5f3a6b209
Usage in ScyllaDB, with some performance numbers, can be viewed here:
https://github.com/scylladb/scylla/commit/efd96a448cca4499fd40df8b3df3f0f8444a1464.
Microbenchmarks see almost 200% improvement while full-system tests see
around 50% improvement, mostly due to improved IPC.
--
You received this message because you are subscribed to the Google Groups
"mechanical-sympathy" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
For more options, visit https://groups.google.com/d/optout.
