[Qemu-discuss] Qemu reports slightly less memory on PXE boot

[Prem Anand Haridoss]

On booting an iso (from the cdrom) with 8G memory, after bootup, I see 8179816 kB as the total memory available.

However on PXE booting the same vCPE livecd iso over a nic, with the same 8G memory, we see only 7857512 kB as the total memory available

 

Is this a bug in qemu? I am using version 2.5.0 (Debian 1:2.5+dfsg-1)

 

Regards

Prem

 

Logs:

=====

On booting iso using cdrom

--------------------------

address@hidden:~/work/tplaf/☸ qemu-system-x86_64 -name Test -nographic -enable-kvm -cpu Haswell -smp 2 -m 8G -cdrom $iso -boot d

 

ISOLINUX 4.05 20121210  Copyright (C) 1994-2011 H. Peter Anvin et al

Press control and F then 1 for help, or ENTER to

boot: live-serial init=/bin/bash

Loading, please wait...

bash: no job control in this shell

root@(none):/#

root@(none):/# cat /proc/meminfo | head -n3

MemTotal:        8179816 kB

MemFree:         8138960 kB

MemAvailable:    8131960 kB

 

On pxe booting the iso over a nic

---------------------------------

address@hidden:~/☸ qemu-system-x86_64 -name Test -nographic -enable-kvm -cpu Haswell -smp 2 -m 8G -netdev user,id=net0,tftp=$HOME/TPLAF//TB2/rtr2/tftp,bootfile=/gpxelinux.0 -device rtl8139,netdev=net0 -boot

 

PXELINUX 6.03 PXE 6.03-pre20 Copyright (C) 1994-2014 H. Peter Anvin et al

boot: Build109.11

Loading memdisk... ok

Loading <deleted>...ok

 

ISOLINUX 4.05 20121210  Copyright (C) 1994-2011 H. Peter Anvin et al

Press control and F then 1 for help, or ENTER to

boot: live-serial init=/bin/bash

Loading, please wait...

bash: no job control in this shell

root@(none):/#

root@(none):/# cat /proc/meminfo | head -n3

MemTotal:        7857512 kB

MemFree:         7816764 kB

MemAvailable:    7809988 kB