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Can we have more details on how your application is communicating with the FPGA ? Is it the application that reads the buffer from the FPGA, or the FPGA that sends interrupt to the kernel (like network cards) ? I expect it to open a block/char in /dev and then communicate with it. This means it uses a driver to do the communication between the application ...


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One option to do a quick test could be to use a KGDB enabled kernel and stop the kernel manually and test, see this link. On another note, things I remember that could cause your pauses: cpufreq, cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_transition_latency, the value is in ns (4000 in my AMD FX(tm)-8120 Eight-Core Processor) shouldn't be a problem, ...


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Not sure if it helps. But if you can write a kernel module that calls the suspend function of another device's kernel module, that may do. Each PCI device can be suspended according to the header file http://www.cs.fsu.edu/~baker/devices/lxr/http/source/linux/include/linux/pci.h#L479 For example, here's Intel e1000 NIC's suspend function ...


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You might be running into trouble because /dev/mem has holes in it: memory locations that don't exist can't be read. strings is designed to read a regular file (or pipe or other input stream) from beginning to end and assumes there can't be holes in its input. It probably aborts the first time it gets a read error, which would correspond to the first hole ...


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Inactive memory is memory that a process used at some point and is still allocated, but which hasn't been used recently. It is the memory that is most likely to be paged out to make room for newly required blocks. Committed memory is the total of all space which has nominally been allocated to processes. It's the aggregate of all memory space processes ...


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Looks like the issue is related to the updates and broken mirrors. Changed the mirror I'm using to a different one, updates were successful. After a reboot, performance became smooth and when I checked the RAM it already has 7.2GB(looks like AMD APU uses RAM too).


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Check /proc/ tree memory file $> cat /proc/meminfo MemTotal: $MEMTOTAL MemFree: $MEMFREE Buffers: $BUFFERS Cached: $CACHED SwapCached: $SWAPCACHED ... ... Check DMESG Log for your Memory $> dmesg | grep "Memory" Invoke dmidecode to learn about your hardware $> dmidecode --type memory Most likely, you are facing a hardware issue. Make sure ...


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Take a look at this script https://github.com/pixelb/scripts/commits/master/scripts/ps_mem.py which we are using regularly to debug our applications. It is not a simple task and the methods differ from kernel to kernel sometimes. From the description of the script you can read the following. # Try to determine how much RAM is currently being used per ...


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I figured you can analyze the /proc/ID/maps file for each process in question - if you list all the mapped pages, discard all executable pages, shared pages and pages that are not mapped to an inode. If you then sum up their sizes (which can be computed from the beginning and ending addresses) then the result is the actual memory pressure of the process. I ...


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Before the introduction of tmpfs / initramfs there was ramdiskused to load the initrdimages, a pre-defined fixed size block devices, I think contiguous, at least on earlier implementations. The block driver itself doesn't have parameters for the memory address, only the size, but the kernel used to load initrd images at a pre-defined address (by config) so ...


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I don't think that huge pages are worth the trouble on a typical desktop use. Data in huge pages is very slightly faster to access, but this requires allocating memory in chunks of 2MB at a time (on x86_64, with similar sizes on other architectures). Most applications allocate memory in far smaller chunks. The two main applications of huge pages in user ...


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I am not an expert on device drivers, however here are some pointers for your R&D: if memory is marked as "reserved", the OS cannot touch it; you will have to find a way to either have the BIOS mark it as available to the OS, or use direct low-level ioctls to control it if Linux could see the memory, you still would not have an easy way to prevent ...


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For anyone else running into the same issue, my problem was indeed caused by Dell Servers being picky about memory module placement. I had originally placed the 4 pairs of 4GB modules in slots 3 & 4 of all four memory risers (the original 4 pairs of 2GB modules I left in slots 1 & 2 of the memory risers). However, for whatever reason Dell Servers ...


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As a tangential point if your threads are created and the thread function exits after doing its job but the VmDATA keeps increasing, then you have a memory leak. Generally when a thread function exits a pthread_exit is implicit but the thread resources are not release until a pthread_join or pthread_detach. So to explicitly release the thread stack from ...


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To see installed memory you can use this command: $ prtconf | grep Memory Memory size: 65408 Megabytes There's also prtdiag -v | grep Memory. Additional methods are shown here: Used memory on Solaris 10.


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you're absolutely right @KG6ZVP this doesn't seem like something you can fix from hardware BIOS level. You have a simple centos 6.5 install which is good on normal hardware such as a laptop or maybe a 1, 2, 3, or or 4 U arch computer. I don't think it will support the amount of memory you have. I've been installing Linux for a long time and my gut feeling ...



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