Charon-SSP Cloud Instance Prerequisites

By selecting an instance type or shape, you select the virtual hardware that will be used for the Charon-SSP host instance in the cloud. Therefore, the selection of an instance type or shape determines the hardware characteristics of the Charon-SSP virtual host hardware (e.g., how many CPU cores and how much memory your virtual Charon host system will have).

Please note:

• If you use a Charon-SSP marketplace image to launch your instance, all Linux host operating system requirements are fulfilled.

• If you use a generic Linux marketplace image to launch your instance, please refer to the Charon-SSP for Linux User's Guide for the software requirements that must be fulfilled.

Charon-SSP General Notes

Please note the following points regarding the sizing guidelines:

• The sizing guidelines below—in particular regarding number of host CPU cores and host memory—show the minimum requirements.
  Every deployment situation must be reviewed and the actual host sizing has to be adapted as necessary. For example, the number of CPU cores available for I/O must be increased if the guest applications produce a high I/O load. Also, a system with many emulated CPUs is typically able to create a higher I/O load and thus the number of CPU cores available for I/O may have to be increased. In a hyper-threading environment, for best performance, the number of CPU cores (i.e., real/physical CPUs) should be sufficient to fulfill CPU requirements of the active emulators, thus avoiding high-workload threads sharing one physical CPU core.

• The CPU core allocation for emulated CPUs and CPU cores for I/O processing is determined by the configuration. See CPU Configuration in the general Charon-SSP User's Guide for more information about this and the default allocation of CPU cores for I/O processing.

Important general information:

• To facilitate a fast transfer of emulator data from one cloud instance to another, it is strongly recommended to store all relevant emulator data on a separate disk volume that can easily be detached from the old instance and attached to a new instance.

• Please make sure to dimension your instance correctly from the beginning (check the minimum requirements below). The Charon-SSP license for Charon-SSP AL is created when the instance is first launched. Changing later to another instance size/type and thereby changing the number of CPU cores will invalidate the license and thus prevent Charon instances from starting (new instance required). If planning to use the Charon-SSP AL instance in AutoVE mode, be sure to include the AutoVE server information before first launch, otherwise the public license servers will be used. The license for Charon-SSP VE is created based on the fingerprint taken on the license server. If the license server is run directly on the emulator host and the emulator host later requires, for example, a change in the number of CPU cores, the license will be invalidated, unless it is transferred out of the system beforehand - then the resulting transfer file and a new C2V file from the changed system can be used to obtain a new license from Stromasys.

Charon-SSP Cloud Instance Prerequisites

Host System CPU Core Requirements

Platform emulation is a complex and CPU-intensive task. The performance of the host processors is the single most important factor which determines the emulated CPU performance.

For the best performance, Stromasys recommends using the fastest available x86_64 processors of the latest generation (but at least with a CPU frequency of 3.0 GHz). At the time of writing, the current generation of Intel server processors is "6th Gen Intel Xeon® Scalable Processors". The current generation of AMD server processors is "5th Generation AMD EPYC™ Processors".

Minimum number of host system CPU cores:

• At least one CPU core for the host operating system, plus:

• For each emulated SPARC system:

  • One CPU core for each emulated CPU of the instance, plus:

  • At least one additional CPU core for I/O processing (at least two additional cores, if server JIT optimization is used). See the CPU Configuration section mentioned above for configuration options. By default, Charon will assign 1/3 (min. 1; rounded down) of the number of CPUs visible to the Charon host to I/O processing.

Host System Memory Requirements

Several components contribute to the overall memory requirements of a Charon-SSP host system:

1. ​​Charon host Linux operating system: at least 4GB of RAM​​, plus:

2. Enough memory for third-party applications (non-emulator services) running on the Linux host, plus:

3. For each emulated SPARC system:

   1. The configured memory of the emulated instance (Solaris RAM), plus:

   2. Dedicated memory for the required SSP services to allow for DIT optimization, emulator requirements, run-time buffers, SMP, graphics emulation, etc.:

      1. Charon-SSP/4M: 1GB of RAM

      2. Charon-SSP/4U/4V (Client JIT):
         1.5GB + (0.5GB x number of emulated CPUs) + (1% of the configured Solaris RAM)

      3. Charon-SSP/4U/4V (Server JIT):
         5GB + (0.5GB x number of emulated CPUs) + (1% of the configured Solaris RAM)

Total memory formula​​:

Total RAM required = Linux OS (4 GB) + SSP Services RAM + Solaris emulated RAM + Third-Party requirements
This formula is derived from data based on actual measurements; it should be applicable to most scenarios. However, there may be use cases that require special consideration. The 0.5GB additional memory per emulated CPU could be reduced to 120MB per emulated CPU in case of small memory configurations (<16GB).

Important note for Server JIT:

The actual memory consumption may exceed the calculated requirements due to:

• Server JIT compilation spikes during peak loads

• Memory fragmentation overhead

• Unpredictable workload patterns

Monitoring the memory utilization on the Charon host system is a critical component of managing the system. If the available free memory goes below 5% of the total memory, an alarm should be raised.

Additional Charon Host Hardware Requirements

In addition to the basic CPU and memory requirements, there are additional aspects regarding the hardware configuration of the Charon-SSP host system. They are described below.

Hyper-threading considerations for the Charon host:

If hyper-threading is enabled on modern x86-64 CPUs, two threads can run on one physical CPU core providing two logical CPUs to the host operating system.

• If possible, disable hyper-threading for the Charon-SSP host system. However, this is frequently not possible in VMware and cloud environments.

• In the case that hyper-threading cannot be disabled, please note:

  • If MMU pass-through is not used, the Charon-SSP hyper-threading configuration option enables Charon-SSP to adapt to such environments.

  • If MMU pass-through is used, the emulator cannot use the automatic handling of hyper-threading. Instead, CPU binding is required. See the CPU Configuration section in your general Charon-SSP User's Guide mentioned above for detailed configuration information.

• Please note: under sustained high workloads, Charon-SSP threads should not share a physical CPU core –enough physical cores should be available on the host system to satisfy the requirements of the configured emulator(s).

Other hardware requirements for the Charon host:

• Charon-SSP/4U+ and Charon-SSP/4V+ must run on physical (baremetal) hardware supporting Intel VT-x/EPT or AMD-v/NPT.

• At least one available USB port (if USB license key is used). More for additional USB devices.

• Single dedicated network adapter for each configured virtual network adapter in Charon-SSP unless the virtual network functionality of Charon-SSP is used. In this case, TAP interfaces attached to a virtual bridge on the host system can be used as the basis for Charon-SSP virtual network adapters. Note that in cloud environments, a virtual bridge cannot be connected to the cloud LAN via a host NIC.

• Free PCI slots to install serial line cards if the Digi PCI pass-through feature is to be used.

• Free PCI or PCIe slots to install GPIB cards if the GPIB PCI pass-through feature is to be used.

• Optical drive if DVD installation media is to be used.

• Enough disk space for the host operating system and any virtual disk/tape container files required by the guest operating system.