You are probably all aware of the Meltdown and Spectre attacks  by
now. The solution adopted by many operating systems is called page
table isolation (e.g. KPTI on Linux) and it may have an impact on
The RabbitMQ team conducted a few tests on various workloads on Ubuntu
14.04 VMs on GCP to learn more about how the solution affects RabbitMQ.
The non-KPTI VM was running Linux 4.4.0-97 while the KPTI-enabled one
was running 4.4.0-109.
Depending on the workload, the throughput of KPTI-enabled deployment
can be reduced by up-to 10%, compared to a non-KPTI deployment. The
description of workloads and the files to reproduce them using BOSH and
CloudFoundry are available on GitHub .
The largest decrease of 10% was observed with a single RabbitMQ node
with 10 queues, 10 producers and 10 consumers on an 8-core VM. The
bottleneck of such a setup is the CPU. In other workloads where the
bottleneck is the disk the decrease is around 5%.
You can find attached a screenshot from our public workloads dashboard ,
demonstrating the decrease (notice `-kpti` deployment names).