HermitCore - A lightweight extreme-scale satellite kernel

The project has just initiated. Further information will be published shortly.

Requirements

• Netwide Assembler (NASM)
• GNU Make, GNU Binutils
• Tools and libraries to build linux, binutils and gcc (e.g. flex, bison, MPFR library, GMP library, MPC library, ISL library)
• genisoimage
• texinfo
• Qemu

Building and testing HermitCore within a virtual machine

1. The build process does only work on a x86-based Linux system.
2. To configure the system, run the configure script in the dirctory, which contains this README. Fine tuning of the installation directories e.g. with the flag --prefix is currently not supported. HermitCore, the cross-compiler and the demo applications will be installed in subdirectories of this repository.
3. Build the Linux kernel, the HermitCore kernel, the corss-compiler and the demo applications with make.
4. Create a virtual machine and boot a small Linux version with make qemu. Per default, the virtual machine has 20 cores, 4 NUMA nodes and 8 GByte RAM. To increase or to decrease the machine size, the label qemu in the Makefile has to be modified.
5. Afterwards, a small Linux system should run, which already includes the patches for HermitCore. For each NUMA node (= HermitCore isle) is in /sys/hermit a directory isleX, where X represents the number of the NUMA node. In this environment, Linux uses only one core. Consequently, 20-1 cores could be mapped to HermitCore isles. For instance, echo 1-4 > /sys/hermit/isle0/cpus boots a HermitCore kernel on core 1-4. The required memory will be allocated from NUMA node 0 (= isle0).
6. HermitCore's kernel messages of isle0 are available via cat /sys/hermit/isle0/log.
7. It exists an virtual IP devices between HermitCore isles and the Linux system (see output of ifconfig). Per default, the Linux system has the IP address 192.168.28.1. The HermitCore isles starts with the IP address 192.168.28.2 for isle 0 and is increased by one for every isle. Please test the connection to isle 0 with ping -c 5 192.168.28.2.
8. All demo applications are mapped into the directory /hermit of the Linux system. All applications are Linux applications with integrated HermitCore binaries. By starting of an application, a Linux process will be created, which sends the HermitCore binary via TCP/IP per default to isle 0. With the environment variable HERMIT_ISLE, the default behavior could be overloaded. The HermitCore isle receives the binary, starts the applications and forward all output messages to the Linux system. For instance, HERMIT_ISLE=0 /hermit/hello_proxy starts the classical HelloWorld demo on isle 0 and the output messages are printed on the Linux system.

Building and testing HermitCore on a real machine

1. In principle you have to follow the tutorial above. After the configuration (step 2 in the above tutorial) go to the subdirectory linux, which contains the source code of the Linux kernel. Configure the kernel with make menuconfig for your system. Be sure, that the option CONFIG_HERMIT_CORE in Processor type and features is enabled.
2. Go back to the root directory of this repository and build with make the Linux kernel, the HermitCore kernel, the cross-compiler and the demo applications.
3. Install the Linux kernel and its initial ramdisk on your system (see descriptions of your Linux distribution).
4. Create the directory hermit in the root directory of your Linux system (mkdir /hermit).
5. Copy the HermitCore kernel and the demo applications to the new directory (cp hermit/hermit.bin /hermit ; cp hermit/tools/iso/* /hermit).
6. The IP device between HermitCore and Linux does currently not support IPv6. Consequently, disable IPv6 by adding following line to /etc/sysctl.conf: net.ipv6.conf.eth0.disable_ipv6 = 1.
7. Per default, the IP device uses a static IP address range. Linux has to use 162.168.28.1, where HermitCore isles start with 192.168.28.2 (isle 0). The network manager must be configured accordingly and consequently the file /etc/sysconfig/network-scripts/ifcfg-mmnif must be created with following contents:

DEVICE=mmnif
BOOTPROTO=none
ONBOOT=yes
NETWORK=192.168.28.0
NETMASK=255.255.255.0
IPADDR=192.168.28.1
NM_CONTROLLED=yes

Finally, boot your system with the new Linux kernel and follow the above tutorial (Building and testing HermitCore within a virtual machine) from point 5.