yOn Mon, 4 Oct 1999, J.D. Bakker wrote:
> At 16:36 +0200 04-10-1999, Adam 'WeirdArms' Wiggins wrote:
> > Priority is build into L4 it uses hard priority with round robin
> >on the same priority level. After thinking about the pre-emption issue
> >though I'm not sure its needed since the critical syscall IPC is about 1us
> >on a 100Mhz mips machine I hope to get something similar for the SA-1100.
>
> For reference:
>
> bash-2.01# ./lat_syscall null
> Simple syscall: 0.6472 microseconds
>
Whats it do? The L4 Null syscall (get_my_id) is much less then IPC
:)
> This on a 220MHz SA-1100, kernel 2.2.12, with not-quite-tuned 60ns EDO
> DRAM, using lat_syscall from lmbench. Surely L4 can beat that ;-)
>
Well on the MIPS 100Mhz single issue cpu its 1us for IPC which
transferes 8 dwords (64bit) of data. I hope to keep the same number of
instructio cycles so about 100 cycles at 200Mhz thats gives us 0.5us to
transfere 8 aarm registers of data or 8 words (32 bit). But I've yet to
get around to writting the IPC path.
Anyone interested in helping is welcome to say so ;) The code is
GPL, just not released until I get IPC working (a month or so... I hope)
Cheers Adam
unsubscribe: body of `unsubscribe linux-arm' to [EMAIL PROTECTED]
