The SCO Embedded Configuration Toolkit is designed to produce SCO UNIX operating environments that work efficiently and effectively within strictly limited RAM resources. An absolute minimum of 4MB of RAM is recommended for all systems (except client controllers and embedded servers). Any available RAM over and above the amount used by the UNIX kernel and filesystem can be used by applications.
A number of limitations are imposed on the runtime environment to maintain this resource limitation, particularly in the number of concurrently running processes and in device support.
The following tables summarize the relevant limitations in a minimum hardware environment:
Table 4-1 Minimum configuration: features
---------------------------------------------------------------------------- Diskless Diskless Clients Disk based NFS Client Feature Servers (Static) Clients Clients Controllers ---------------------------------------------------------------------------- OS RAM usageNotes:∗ n/a 1.41MB 1.45MB 1.77MB 2.0MB Application RAM∗ ∗ n/a 2.59MB 2.55MB 2.23MB 2.0MB OS disk usage 12MB∗ ∗ ∗ n/a 18MB+ 2MB++ 20MB++ Login yes no no no no
Table 4-2 Minimum configuration: additional functionality
------------------------------------------------------------------- Diskless Client Size Disk based Client Size Added Functionality Increase (DLL) Increase ------------------------------------------------------------------- IBM 4690 960KB 280KB X, no mouse 2.39MB X, with mouse 2.42MB NetBIOS 436KB SNMP 604KB NFS (non-root) 568KB SLIP n/a 240KB PPP n/a 640KB