Thanks for your reply. I also think that using shared memory is THE solution to move large block of data between user space and RT LINUX.
But, I think that the use of RT Fifo should not affect IRQ latency on a Real Time OS (a can see on my oscilloscope IRQ latency > 1ms !!! when i'm using rtl_put() with 1,5 Mbytes under RTL2.2 / kernel 2.2.14 / Pentium 266 MMX). Somebody know if change have been made on RT FIFO code ( RTL 2.2 -> RTL 3.1) to reduce IRQ latency? G�rard ----- Original Message ----- From: "Norm Dresner" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, October 31, 2001 2:51 AM Subject: Re: [rtl] use of RT Fifo leads to IRQ be lost RTL 2.2 > This doesn't seem like a good design to me. Why can't you > write the data to shared memory (very fast) and just send a > pointer through the FIFO telling the user-task where it can > find the data. > > Norm > > ----- Original Message ----- > From: G�rard LASSAILLY > To: [EMAIL PROTECTED] > Sent: Tuesday, October 30, 2001 4:47 PM > Subject: [rtl] use of RT Fifo leads to IRQ be lost RTL 2.2 > > > I'm using 4 RT Fifo under RT Linux 2.2. > I write blocs of 1.4 Mbytes in RT FIFO (1.4 Mbytes by > rtf_put() ). > This write in RT Fifo is repeat 25 times by second. > > During this, IRQ are lost or delayed. > > I don't use RT Fifo in ISR but only to communicate between > RT task and user task under LINUX. > > I think that IRQ are masked during rtf_put() during a long > time. > > Some knowledge please ? > Do you know if RT Linux 3.0 or 3.1 workaround this > probleme? > > Thanks for your reply. > > -- [rtl] --- > To unsubscribe: > echo "unsubscribe rtl" | mail [EMAIL PROTECTED] OR > echo "unsubscribe rtl <Your_email>" | mail [EMAIL PROTECTED] > -- > For more information on Real-Time Linux see: > http://www.rtlinux.org/ > -- [rtl] --- To unsubscribe: echo "unsubscribe rtl" | mail [EMAIL PROTECTED] OR echo "unsubscribe rtl <Your_email>" | mail [EMAIL PROTECTED] -- For more information on Real-Time Linux see: http://www.rtlinux.org/
