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Optimal timing slice , Thread qn
- From: steve smith <mister dot steve dot smith at gmail dot com>
- To: ecos-discuss at sources dot redhat dot com
- Cc: mister dot steve dot smith at gmail dot com
- Date: Tue, 18 Jan 2005 22:57:44 -0800
- Subject: [ECOS] Optimal timing slice , Thread qn
- Reply-to: steve smith <mister dot steve dot smith at gmail dot com>
Hey All
I got 2 more questions
10 ms is the default time slice period per thread. Are there any
plots/metrics/graphs on the effect of size of this time slice on
various performance parameters. I would imagine having a too big a
slice is wasteful.... and too small a slice causes inefficient
frequent context switching. so probably a optima exists. How would one
gauge that?
Also I have two thread at the same priority level one uses
cyg_io_read() to read from a USART and the other uses cyg_io_write()
to write to same USART. No flow control is used. The problem is that
if i don't put a delay at the end of them OR if i don't do
cyg_thread_yield() at the end, then only the cyg_io_write() thread is
run and the reading from USART doesn't take place. Both cyg_io_read
and cyg_io_write are protected by mutexes in their respective
threads.Why isn't the read thread ready for execution?.
thanks
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