Installation guide
Application limitations
17
Applications with high I/O throughput requirements should use the para-virtualized drivers for fully
virtualized guests. Without the para-virtualized drivers certain applications may be unstable under
heavy I/O loads.
The following applications should be avoided for their high I/O requirement reasons:
• kdump server
• netdump server
You should carefully evaluate databasing applications before running them on a virtualized guest.
Databases generally use network and storage I/O devices intensively. These applications may not be
suitable for a fully virtualized environment. Consider the para-virtualized drivers or PCI passthrough for
increased I/O performance. Refer to Chapter 11, KVM Para-virtualized Drivers for more information on
the para-virtualized drivers for fully virtualized guests. Refer to Chapter 12, PCI passthrough for more
information on the PCI passthrough.
Other applications and tools which heavily utilize I/O or require real-time performance should be
evaluated carefully. Using full virtualization with the para-virtualized drivers (refer to Chapter 11, KVM
Para-virtualized Drivers) or PCI passthrough (refer to Chapter 12, PCI passthrough) results in better
performance with I/O intensive applications. Applications still suffer a small performance loss from
running in virtualized environments. The performance benefits of virtualization through consolidating to
newer and faster hardware should be evaluated against the potential application performance issues
associated with using virtualization.