• What access does a MDCS worker have to the local drives? Can this be limited to temporary directories to protect against accidental corruption of the OS or other parts of the local computer? How tightly can read/write access be controlled for the worker?
MDCS provides the access level of the user as whom the service runs. If you run the service as a reduced privilege user, then the service can only access those files that the particular reduced privilege user can access. That is, by running as a reduced privilege user, you can protect your OS against the service.
• What is the priority level of worker processes? Can it be set low so that other processes on the computer have priority and the worker only uses idle resources?
MATLAB doesn’t provide a way to directly control priority level, but you can set the priority/nice level of its processes from within your operating system.
• How much RAM can it use? Is there a way to protect a worker node from exceeding available RAM and thus becoming unresponsive due to excessive disk swapping?
MATLAB doesn’t control the amount of RAM used by the service; it lets the operating system manage RAM resources. If a process uses too much RAM it is up to the operating system to control / reduce the processes usage.
• How much local disk space can it use? Is there any protection against filling up the local disk?
MATLAB allows the service to use as much disk space as is allowed to the user as whom the service runs. If your disk system supports quota, and you set the quota of the MDCE user, you could limit the amount of disk usage.
• What are the options for setting network disk assess for workers?
Access is also limited by the permissions of the user as whom the service runs. The only way to give shared network drive access to workers is to set MDCEUSER and MDCEPASS on every node computer for a user who has network access permission, or to use SECURITY_LEVEL=3 to have user-specific permissions. With security level 3, permissions will be based on the submitting user, rather than the user as whom the service runs. Please note that with UNIX, if running at security level 3, the service process MUST run as root otherwise it will not be able to become the submitting user.
