On 4/10/06, sudheer <urwithsudheer@xxxxxxxxx> wrote:
Hard disks is a major source of troubles when RT is needed .. so what if i run linux 2.6 on a disk less system .. rootfs is on memory (ramdisk), swap is not configured and preemption is configured.. then can i say that accessing files will be a deterministic operation? how does this helps determinism in Linux and how it doesn't
thanks
MHD.Tayseer
Hi MHD.Tayseer Alquoatli,
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in other words, will non-deterministic operations on linux still be non-deterministic when running RTLinux ?
by the way, can anybody give examples of non-deterministic operation in Linux kernel that are not cause of a non-deterministic nature of the hardware--------
To my knowledge, RTkernel takes or executes only the real-time activities. all the non-rt activities will be assigned to normal kernel like accesing data from files , etc when no rt task are ready to run.
And so i dont think , we can listen to songs( say a non-real-time activity) parallely in RTlinux while running real-time activities .
Accessing data from harddisks , writing data to files are non-determenistic.
Hard disks is a major source of troubles when RT is needed .. so what if i run linux 2.6 on a disk less system .. rootfs is on memory (ramdisk), swap is not configured and preemption is configured.. then can i say that accessing files will be a deterministic operation? how does this helps determinism in Linux and how it doesn't
thanks
MHD.Tayseer
eg: Data recieved from sensors will be stored in buffers - real-time (rtkernel)
Data from buffers to files is nrt activity . (normal kernel)
Programmer s'd take care to give sufficient time for nrt activities also.
ThanksSudheer.A
