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46d88d8dba
Previous patch handled the runtime case where a non-x86 host is fetching /proc/cpuinfo data for a microcode info that we know it doesn't exist. This change alone speeded everything by a bit for non-x86, but there is at least one major culprit left. qemuxml2argvtest does several arch-specific tests, and a good chunk of them are x86 exclusive. This means that 'hostArch' will be seen as x86 for these tests, even when running in non-x86 hosts. In a Power 9 server with 128 CPUs, qemuxml2argvtest takes 298 seconds to complete in average, and 'perf record' indicates that 95% of the time is spent in virHostCPUGetMicrocodeVersion(). This patch mocks virHostCPUGetMicrocodeVersion() to always return 0 in the tests, avoiding /proc/cpuinfo reads. This will make all tests behave arch-agnostic, and the microcode value being 0 has no impact on any existing test. This is a CI speed across the board for all archs, including x86, given that we're not reading /proc/cpuinfo in the tests. For a Thinkpad T480 laptop with 8 Intel i7 CPUs, qemuxml2argvtest went from 15.50 sec to 12.50 seconds. The performance gain is even more noticeable for huge servers with lots of CPUs. For the Power 9 server mentioned above, this patch speeds qemuxml2argvtest to 9 seconds, down from 298 sec. Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com> Reviewed-by: Ján Tomko <jtomko@redhat.com> Signed-off-by: Ján Tomko <jtomko@redhat.com>
libvirt library code README
===========================
The directory provides the bulk of the libvirt codebase. Everything
except for the libvirtd daemon and client tools. The build uses a
large number of libtool convenience libraries - one for each child
directory, and then links them together for the final libvirt.so,
although some bits get linked directly to libvirtd daemon instead.
The files directly in this directory are supporting the public API
entry points & data structures.
There are two core shared modules to be aware of:
* util/ - a collection of shared APIs that can be used by any
code. This directory is always in the include path
for all things built
* conf/ - APIs for parsing / manipulating all the official XML
files used by the public API. This directory is only
in the include path for driver implementation modules
* vmx/ - VMware VMX config handling (used by esx/ and vmware/)
Then there are the hypervisor implementations:
* bhyve - bhyve - The BSD Hypervisor
* esx/ - VMware ESX and GSX support using vSphere API over SOAP
* hyperv/ - Microsoft Hyper-V support using WinRM
* lxc/ - Linux Native Containers
* openvz/ - OpenVZ containers using cli tools
* qemu/ - QEMU / KVM using qemu CLI/monitor
* remote/ - Generic libvirt native RPC client
* test/ - A "mock" driver for testing
* vbox/ - Virtual Box using native API
* vmware/ - VMware Workstation and Player using the vmrun tool
* xen/ - Xen using hypercalls, XenD SEXPR & XenStore
Finally some secondary drivers that are shared for several HVs.
Currently these are used by LXC, OpenVZ, QEMU and Xen drivers.
The ESX, Hyper-V, Remote, Test & VirtualBox drivers all
implement the secondary drivers directly
* cpu/ - CPU feature management
* interface/ - Host network interface management
* network/ - Virtual NAT networking
* nwfilter/ - Network traffic filtering rules
* node_device/ - Host device enumeration
* secret/ - Secret management
* security/ - Mandatory access control drivers
* storage/ - Storage management drivers
Since both the hypervisor and secondary drivers can be built as
dlopen()able modules, it is *FORBIDDEN* to have build dependencies
between these directories. Drivers are only allowed to depend on
the public API, and the internal APIs in the util/ and conf/
directories