Making New Server-Virtualization Capabilities a Reality

One of the most rewarding aspects of my work at Intel is seeing the new capabilities built in to Intel silicon that are then brought to life on an ISV partner’s product. It is this synergy between Intel and partner technologies where I see the industry and customers really benefit.

Two of the newer examples of this kind of synergy are made possible with Citrix XenServer 7.0—Supervisor Mode Access Prevention (SMAP) and Page Modification Logging (PML). Both capabilities are built in to the Intel Xeon processor E5 v4 family, but can only benefit customers when a server-virtualization platform is engineered to use them. Citrix XenServer 7.0 is one of  the first server-virtualization platforms to do that with SMAP and PML.

Enhancing Security with Supervisor Mode Access Prevention (SMAP)

SMAP is not new in and of itself. Intel introduced SMAP for Linux on 3rd generation Xeon processors, SMAP is new to virtualization though. Intel added SMAP code to the Citrix Xen hypervisor in Xen Project. Citrix then worked with the code in Xen, and XenServer 7.0 makes SMAP a reality for server virtualization.


Figure 1:  SMAP prevents the hypervisor from accessing the guests’ memory space other than when needed for a specific function

SMAP helps prevent malware from diverting operating-system access to malware-controlled user data, which helps enhance security in virtualized server environments. SMAP aligns with the Intel and Citrix partnership where Intel and Citrix regularly collaborate to help make a seamless, secure mobile-workspace experience a reality.

Improving Performance with Page Modification Logging (PML)

PML improves performance during live migrations between virtual server hosts. As with SMAP, PML capabilities are built in to the Intel Xeon processor E5 v4 family, and XenServer 7.0 is one of the first server-virtualization platforms to actually enable PML in a virtualized server environment.


Figure 2:  With PML, CPU cycles previously used to track guest memory-page writes during live migration are available for guest use instead

Read More

I haven’t gone into detail on SMAP or PML or how they work. Instead, I invite you to read about them and how they add to the already strong XenServer virtualization platform and Intel Xeon processor E5 family in the Intel and Citrix solution brief, “New Capabilities with Citrix XenServer and the Intel Xeon Processor E5 v4 Family.” I also invite you to follow me and my growing #TechTim community on Twitter: @TimIntel.

Published on Categories Data CenterTags
Tim Allen

About Tim Allen

Tim is a strategic marketing manager for Intel with specific responsibilities related to the cloud, big data, analytics, datacenter appliances and RISC migration. Tim has 20+ years of industry experience including work as a systems analyst, developer, system administrator, enterprise systems trainer, product marketing engineer and marketing program manager. Prior to Intel Tim worked at Tektronix, IBM, Intersolv, Sequent and Con-Way Logistics. Tim holds a BSEE in computer engineering from BYU, PMP certification and a MBA in finance from the University of Portland. Specialties include - PMP, MCSE, CNA, HP-UX, AIX, Shell, Perl, C++