Hi everyone,
I was wondering if anyone could
answer my confusion here. I am using qemu-kvm 0.12.1 installed with
centos-6.5. I would like to use large pages to back my guest vm, so I
did it as this:
http://www.linux-kvm.org/page/UsingLargePages,
and added "-mem-path /hugetlbfs" in the command to create VM. When
things went well, after creating vm, I type "tail /proc/meminfo", it
would show like this, which means "HugePages" was used:
address@hidden domain]# tail /proc/meminfo
VmallocChunk: 34359481380 kB
HardwareCorrupted: 0 kB
AnonHugePages: 1368064 kB
HugePages_Total: 512
HugePages_Free: 384
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB
DirectMap4k: 6144 kB
DirectMap2M: 12552192 kB
However
if I add "root=/dev/vda1" in the command to create vm, which looks like
"-append root=/dev/vda1 console=ttyS0" in command line, then "-mem-path
/hugetlbfs" doesn't work:
address@hidden domain]# tail /proc/meminfo
VmallocChunk: 34359481380 kB
HardwareCorrupted: 0 kB
AnonHugePages: 1390592 kB
HugePages_Total: 512
HugePages_Free: 512
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB
DirectMap4k: 6144 kB
DirectMap2M: 12552192 kB
Does
anyone know how does "root=/dev/vda1" conflict with hugepages and how
do I use both of them to create a VM? I am actually using an xml file to
create VM, and those commands I mentioned above are shown in "ps aux |
grep qemu".
Thanks,
Min