Difference between revisions of "Xen 4.2 Limits"
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== Other Limits == |
== Other Limits == |
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− | * Maximum of 32K interrupts and 2k PCI segments: this limits the number of devices that can be |
+ | * Maximum of 32K interrupts and 2k PCI segments: this limits the number of devices that can be used in two ways: |
− | used in two ways. |
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** The number of devices many can be attached to the system must fit into 2k PCI segments, i.e. 2k * 256 [buses] * 32 [devices] * 8 [functions]) |
** The number of devices many can be attached to the system must fit into 2k PCI segments, i.e. 2k * 256 [buses] * 32 [devices] * 8 [functions]) |
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** The number of hardware interrupts they may surface (one would expect at least one interrupt per device function, so this is the stricter of the two limitations). |
** The number of hardware interrupts they may surface (one would expect at least one interrupt per device function, so this is the stricter of the two limitations). |
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+ | [[Category:Xen]] |
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+ | [[Category:Xen 4.2]] |
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+ | [[Category:Users]] |
Revision as of 16:53, 13 August 2012
This document contains information about limits of Xen 4.2.
CPUs & Memory
- Xen can scale up to 4,095 host CPUs with 5Tb of RAM.
- Using Para Virtualization (PV), Xen supports a maximum of 512 VCPUs with 512Gb RAM per guest.
- Using Hardware Virtualization (HVM), Xen supports a maximum of 128 VCPUs with 512Gb RAM per guest.
Other Limits
- Maximum of 32K interrupts and 2k PCI segments: this limits the number of devices that can be used in two ways:
- The number of devices many can be attached to the system must fit into 2k PCI segments, i.e. 2k * 256 [buses] * 32 [devices] * 8 [functions])
- The number of hardware interrupts they may surface (one would expect at least one interrupt per device function, so this is the stricter of the two limitations).