An official response from Mongo on 1/6/2018 (emphasis mine):
Recently disclosed research regarding security vulnerabilities in
almost all modern processors such as Intel and AMD (CVE-2017-5715,
CVE-2017-5753, and CVE-2017-5754) has prompted public and private
institutions, including cloud providers, to patch OS and hypervisor
infrastructures. These patches disable performance optimizing features
of CPUs, and it is expected that, regardless of OS or cloud provider,
all workloads will see a performance impact. We are investigating the
performance implications of these patches to MongoDB on both OS
kernels as well as cloud hypervisors.
Hypervisor Patch Impact
As a result of the patches applied by AWS
between January 3rd and January 5th, 2017, we have observed the
For high-load benchmarks (e.g. YCSB) we measured a 10-15% impact on
throughput with some exceptional cases that are still being studied.
We believe these results are consistent with other industry research.
We will release additional results (including additional cloud
providers) in the coming days.
Kernel Patch Impact
This is the impact that customers can expect to
see when they apply the recommended patches to their cloud VMs or
At this time we have not seen a substantial signal (either better or
worse) on major distributions such as Amazon Linux, Red Hat Enterprise
Linux, and Ubuntu. Based on the industry research we expect that there
will be some measurable performance impact (although yet to be
quantified). We will have additional results made available in the
coming days. If you have any questions or concerns, please file a
ticket in the Support Portal.
You can read Intel’s white paper to learn more about these