Klaas Gadeyne wrote:
On Fri, 2 Dec 2005, Philippe Gerum wrote:
Klaas Gadeyne wrote:
[...]
For comparison, on the same hardware platform: - the RTAI
lxrt-latency on rtai 3.0r5 (adeos oldgen r18c1
patch for 2.4.31 also) test reports 38 usec
- the latency test of xenomai 2.01 running on a 2.6.14-ipipe-1.0-10
kernel resulted in a latency of 80 usec.
80 us on 2.6 is clearly pathological if 2.4 gives 30 us. All tests
using 2.6.14-1.0-10 on dual SMP 750Mhz and 2.8Ghz, Geode 266 Mhz,
Celeron 1Ghz, Centrino 1.6 Mhz and Pentium 90Mhz show a slight
advantage for 2.4 over 2.6 (1-3%), but still in the error margin, I
think. Maybe some option is enabled in your 2.6 configuration that
might trigger this very high value?
I rechecked the 2.6 config. Apart from the lapic option, which I
couldn't enable with xenomai [*], I can't see something obvious that I
would have missed. I'm sending you the config file in private.
Note that I haven't tested the 2.6 kernel with xenomai-trunk yet though...
thx,
Klaas
[*] When enabling local apic in the kernel configuration and booting
with the lapic option, I get
Disable APIC support or pass "lapic" as boot param.
lapic=1 on your boot line. This is not a Xeno issue, but a Linux kernel
requirement. Using the local APIC is even recommended when available on
your hw with Xeno.
while loading xeno_hal.
--
Philippe.
