From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <46124C61.3070107@domain.hid> Date: Tue, 03 Apr 2007 14:45:21 +0200 From: Gilles Chanteperdrix MIME-Version: 1.0 Subject: Re: [Xenomai-help] large latencies on a Dell D620 dual core laptop References: <20070403143122.4ac4ffaf@domain.hid> In-Reply-To: <20070403143122.4ac4ffaf@domain.hid> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Daniel Simon Cc: xenomai@xenomai.org Daniel Simon wrote: > Hello all, > > I have very high latencies running Xenomai on my new laptop. > It is a dell D620 dual core laptop with the following > configuration: > > kernel 2.6.20.3, xenomai 2.3.1, adeos-ipipe-2.6.20-i386-1.7-03.patch > compiled with gcc-4.1.1 (fedora core 6), cpuinfo is attached > > kernel config file are attached, to summarize: > > no HPET, no APM, no CPU_FREQ, no ACPI_PROC > CONFIG_XENO_HW_SMI_APMC must be enabled, otherwise the kernel does not boot > > here is a sample of the latency test trace: > > root@domain.hid$ ./latency -f > == Sampling period: 100 us > == Test mode: periodic user-mode task > == All results in microseconds > warming up... > RTT| 00:00:01 (periodic user-mode task, 100 us period, priority 99) > RTH|-----lat min|-----lat avg|-----lat max|-overrun|----lat best|---lat worst > RTD| 5.463| 5.823| 112.608| 1| 5.463| 112.608 > RTD| 5.484| 6.109| 1414.435| 32| 5.463| 1414.435 > RTD| 5.388| 6.025| 344.315| 37| 5.388| 1414.435 > RTD| 5.432| 6.149| 1549.593| 69| 5.388| 1549.593 > RTD| 5.468| 5.769| 32.653| 69| 5.388| 1549.593 > RTD| 5.447| 6.183| 1671.993| 109| 5.388| 1671.993 > RTD| 5.506| 6.135| 2935.370| 139| 5.388| 2935.370 > RTD| 5.406| 6.753| 1505.142| 200| 5.388| 2935.370 > RTD| 5.456| 5.827| 36.626| 200| 5.388| 2935.370 > RTD| 5.041| 6.138| 1393.665| 229| 5.041| 2935.370 > RTD| 5.503| 5.778| 52.663| 229| 5.041| 2935.370 > RTD| 5.506| 6.138| 1691.224| 263| 5.041| 2935.370 > > I also disabled the USB emulation in BIOS, also boot in runlevel 3 > (without X), but that does not improve this bad behavior. > > Any idea? Is it possible to be a rt_pathological laptop? Maybe you could compile Xenomai support as modules, and disable CONFIG_XENO_HW_SMI_APMC ? If this does not work, I am afraid you are in the "out of luck" case of Xenomai TROUBLESHOOTING file. -- Gilles Chanteperdrix