Peter942
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Re: Intel® Core™ i3-12100, MSI delay
Wincent_intel We use an Xilinx FPGA. We do now indept timings measurements by FPGA scope. The MSI interrupt is send by Xilinx software. I want to check tomorrow about the Xilinx type. We found out that we lost 10us before the standard software block PCIe wrapper from Xilinx send the MSI interrupt. But still we see lot of delay variation between 5-15us before the interrupt handler is started. We have no detail what are the timings cost to start an interrupt function in the intel core. We have disable Hyperthreading and disable all power optimizations from the CPU. Also there is no extra graphic card in the system and only traffic to the LAN port is ongoing. Is there any timing information about interrupthandling inside a CPU? Is this for everyone visible? Otherwise I can send more details about the issue. Theon1.5KViews0likes0CommentsIntel® Core™ i3-12100, MSI delay
Dear People For a medical system we use an Intel® Core™ i3-12100 system with a specific FPGA card on PCIe slot1 (close to CPU). The card has a reference clocks and generate MSI interrupts. We see on this system significant additional latency of >20us compared with e 10e generation CPU. That is the time that the interrupt is started to send by MSI and when the interrupt is receiving and start the interrupt handler on CPU side. We use Vxworks Realtime OS. Before the interrupt is send the time is stored on FPGA card. When the CPU received the interrupts the time is requested from the FPGA card. Of course there are some time overhead on this. Is there any information available about the timing or MSI message transport time before the interrupt is received on CPU level? I can not found any good information in 325462-sdm-vol-1-2abcd-3abcd-4 (1).pdf We use also a process to send data from FPGA (PCIe) to CPU memory by DMA started from FPGA side. How is the L1,l2,L3 cash synchronized when due external DMA the memory is updated and some parts is also in L-X cash? Result this in extra delay? Where can I found more information about this?1.6KViews0likes7Comments