Dynamic memory CentOS 6 on Hyper-V 3 with Linux Integration

[m.allan]

Hi!
I use a VM with CentOS6 64 Bits on Hyper-V 3 and Linux Integration Services 3.5. The Dynamic memory is working, but when I use the cln top, free -m or cat /proc/meminfo, the information of memory in usage is wrong! For example:

#cat /proc/meminfo
MemTotal: 2947764 kB
MemFree: 266828 kB
Buffers: 3936 kB
Cached: 12856 kB
SwapCached: 108 kB
Active: 19204 kB
Inactive: 34988 kB
Active(anon): 10872 kB
Inactive(anon): 26812 kB
Active(file): 8332 kB
Inactive(file): 8176 kB
Unevictable: 0 kB
Mlocked: 0 kB
SwapTotal: 1048568 kB
SwapFree: 1047868 kB
Dirty: 4 kB
Writeback: 0 kB
AnonPages: 37332 kB
Mapped: 7568 kB
Shmem: 280 kB
Slab: 60900 kB
SReclaimable: 8720 kB
SUnreclaim: 52180 kB
KernelStack: 1536 kB
PageTables: 4176 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 2522448 kB
Committed_AS: 127464 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 46816 kB
VmallocChunk: 34359621288 kB
HardwareCorrupted: 0 kB
AnonHugePages: 0 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB
DirectMap4k: 8128 kB
DirectMap2M: 3137536 kB

See, "MemFree: 266828 kB", on Hyper-V, the information is 2,3GB of free memory! If i use the cln stress to test the memory, the information of free memory change to the correct information!

#lsmod
Module Size Used by
xt_state 1492 1
xt_multiport 2700 887
iptable_mangle 3349 0
iptable_filter 2793 1
ipt_MASQUERADE 2466 0
ipt_REJECT 2351 0
ipt_LOG 5845 0
nf_nat_ftp 3507 0
nf_conntrack_ftp 12913 1 nf_nat_ftp
iptable_nat 6158 0
ip_tables 17831 3 iptable_mangle,iptable_filter,iptable_nat
nf_nat 22759 3 ipt_MASQUERADE,nf_nat_ftp,iptable_nat
nf_conntrack_ipv4 9506 4 iptable_nat,nf_nat
nf_conntrack 79758 7 xt_state,ipt_MASQUERADE,nf_nat_ftp,nf_conntrack_ftp,iptable_nat,nf_nat,nf_conntrack_ipv4
nf_defrag_ipv4 1483 1 nf_conntrack_ipv4
ipv6 317340 144
hid_hyperv 4350 0
sg 29350 0
hv_netvsc 23702 0
hv_utils 9149 0
hv_balloon 12019 0 [permanent]
microcode 112685 0
hyperv_fb 7769 1
i2c_piix4 12608 0
i2c_core 31084 1 i2c_piix4
ext4 374902 2
jbd2 93427 1 ext4
mbcache 8193 1 ext4
sd_mod 39069 5
crc_t10dif 1541 1 sd_mod
pata_acpi 3701 0
ata_generic 3837 0
hv_storvsc 11323 3
hv_vmbus 144850 6 hid_hyperv,hv_netvsc,hv_utils,hv_balloon,hyperv_fb,hv_storvsc
dm_mirror 14384 0
dm_region_hash 12085 1 dm_mirror
dm_log 9930 2 dm_mirror,dm_region_hash
dm_mod 84209 2 dm_mirror,dm_log

[Super Jamie]

Look up "memory balloon" on Google.

That is one of the things the Linux Integration Services do. You can see the hv_balloon driver is installed.

[m.allan]

Thank you