Hi, everyone
In an environment with multiple host machines, I want to select a suitable
host automatically on which I run a VM depending on machine's load.
Libvirt has APIs to get host machine's information,
but I think these APIs aren't enough for above purpose.
So I suggest below changes. What do you think?
* virNodeGetInfo()
This API can get "CPU frequency"(mhz member of virNodeInfo) from
"cpu MHz" of /proc/cpuinfo.
This value isn't constant, because it may be decrease by
power saving feature.(cf. cpuspeed on RHEL)
This value is very useful for getting *present* cpu frequency, but I
want to get Maximum CPU frequency, too.
I want to add max_mhz member in struct virNodeInfo from
/sys/device/system/cpu/cpuXX/cpufreq/cpuinfo_max_freq.
* virNodeGetFreeMemory()
This API returns amount of free memory of the host machine's all
node, but this value doesn't include host's cache/buffer memory.
For above purpose, it would be more suitable to account cache/buffer
as free memory, because most of cache/buffer memory are reclaimable.
But I think virNodeGetFreeMemory()'s ABI should not change easily.
I want to add function virNodeGetCacheBufferMemory(). It returns
amount of cache + buffer memory from /proc/meminfo.
* virSysinfoRead()
This API is completely internal.
But DMI type1 information(dmidecode -t1) is useful for above
purpose, because it's one of the information which suppose to
processing capacity about host machine.
I want to export virSysinfoRead() to user.
--
Minoru Usui <usui(a)mxm.nes.nec.co.jp>