Comtrol eCos - Manual (Page 97)

Kernel Real-time Characterization
Scheduler unlock [many low priority threads]
This test measures the cyg_scheduler_unlock() call. There are many other threads in the system which are
runnable but are lower priority than the main thread. The purpose of this test is to determine the cost of having
additional threads in the system when the scheduler is activated by way of
cyg_scheduler_unlock() .
Mutex Primitives
Init mutex
This test measures the cyg_mutex_init() call. A number of separate mutex variables are created. The
purpose of this test is to measure the cost of creating a new mutex and introducing it to the system.
Lock [unlocked] mutex
This test measures the cyg_mutex_lock() call. The purpose of this test is to measure the cost of locking a
mutex which is currently unlocked. There are no other threads executing in the system while this test runs.
Unlock [locked] mutex
This test measures the cyg_mutex_unlock() call. The purpose of this test is to measure the cost of unlocking
a mutex which is currently locked. There are no other threads executing in the system while this test runs.
Trylock [unlocked] mutex
This test measures the cyg_mutex_trylock() call. The purpose of this test is to measure the cost of locking
a mutex which is currently unlocked. There are no other threads executing in the system while this test runs.
Trylock [locked] mutex
This test measures the cyg_mutex_trylock() call. The purpose of this test is to measure the cost of locking
a mutex which is currently locked. There are no other threads executing in the system while this test runs.
Destroy mutex
This test measures the cyg_mutex_destroy() call. The purpose of this test is to measure the cost of deleting
a mutex from the system. There are no other threads executing in the system while this test runs.
Unlock/Lock mutex
This test attempts to measure the cost of unlocking a mutex for which there is another higher priority thread
waiting. When the mutex is unlocked, the higher priority waiting thread will immediately take the lock. The
time from when the unlock is issued until after the lock succeeds in the second thread is measured, thus giving
the round-trip or circuit time for this type of synchronizer.
Mailbox Primitives
Create mbox
This test measures the cyg_mbox_create() call. A number of separate mailboxes is created. The purpose of
this test is to measure the cost of creating a new mailbox and introducing it to the system.
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