embOS – High Performance & Low Resource Usage
High performance combined with low resource usage has always been a major design consideration.
Resource usage of different operating systems
The actual resource usage depends on many factors (CPU, compiler, memory model, optimization, configuration, etc.). Therefore, these values are neither precise, nor guaranteed – but they give you a good idea of the memory requirements. In the table below, which is for a 32 bit target and XRelease build, you will find minimum ROM and RAM size requirements.
| Resource usage | Value |
|---|---|
| Kernel size (ROM) | approx. 1700 Byte |
| Kernel RAM usage | 71 Byte |
| RAM usage per task control block | 36 Byte |
| RAM usage per resource semaphore | 16 Byte |
| RAM usage counting semaphore | 8 Byte |
| RAM usage per mailbox | 24 Byte |
| RAM usage per software timer | 20 Byte |
| RAM usage task event | 0 Byte |
| Maximal number of tasks | Unlimited (by available RAM only) |
| Maximal number. of mailboxes | Unlimited (by available RAM only) |
| Maximal number of semaphores | Unlimited (by available RAM only) |
| Maximal number of software timers | Unlimited (by available RAM only) |
| Maximal number of task priorities | Unlimited |
| Maximal number of tasks with identical priorities (Round robin scheduling) | Unlimited |