Impact of HyperThreadingMitigation introduced in IBM PureApplication System 2.2.6.0 or IBM Cloud Pak System 2.3.0.0

Originally posted on IBM Developer blog “Exploring PureApplication System, Software Service and more”  by Hendrik van Run on 24 July 2019 (344 visits)

Clients planning to upgrade to IBM PureApplication System 2.2.6.0 or IBM Cloud Pak System 2.3.0.0 should be aware that IBM has introduced HyperThreadingMitigation. This impacts Intel based systems where the Side-Channel-Aware Scheduler on the ESXi has been enabled. Note that since the aforementioned releases use VMware 6.5, it is Side-Channel-Aware Scheduler V1 that has been enabled.

IBM has just released this technote, which provides guidance for clients to determine potential impact of having the Side-Channel-Aware Scheduler enabled. This security measure helps protect clients from CVE -2018-3646, something most know as the Meltdown and Spectre vulnerabilities of Intel (and other) processors that were widely publicised last year. Ultimately clients will have to balance performance and security here. IBM has prioritised security by default in its appliances, but for those clients who prefer another option IBM can help.