I’m no expert here, but here’s something: Box 1, no NUMA: ~$ dmesg | grep -i numa [ 0.000000] No NUMA configuration found Box 2, some NUMA: ~$ dmesg | grep -i numa [ 0.000000] NUMA: Initialized distance table, cnt=8 [ 0.000000] NUMA: Node 4 [0,80000000) + [100000000,280000000) -> [0,280000000)
Find the module in the sysfs tree. In this case it was in /sys/bus/usb-serial/drivers/cp2101 In this directory, there is a new_id file entry that can be used to dynamically add VID PID pair like this : echo VID PID >new_id Here is a LWN entry about this feature
Determining why jupyter notebook kernel dies can be daunting sometimes. When kernel dies as a result of library issues, you might not get any feedback as to what is causing it. Try running the code that is causing the kernel to die in a terminal or in ipython. One common issue I have identified is … Read more
You should check if your distribution is using the vanilla GLIBC or the EGLIBC fork (Debian and Ubuntu have switched to EGLIBC EDIT: they switched back around 2014). Anyway, the repository browser for GLIBC is at http://sourceware.org/git/?p=glibc.git http://code.woboq.org/userspace/glibc/, posted by @guruz below, is a good alternative. The source is a bit complicated by the presence … Read more
If you’re doing assembly programming under Windows you don’t do manual syscalls. You use NTDLL and the Native API to do that for you. The Native API is simply a wrapper around the kernelmode side of things. All it does is perform a syscall for the correct API. You should NEVER need to manually syscall … Read more
Linux: When swap file is used the Page Table Entry gets updated with one marked as invalid and holding information about where it is saved in the swap file. That is: an index to the swap_info array and an offset within the swap_map. Example from (an a bit old) Page Table Entry type (pte_t) on … Read more
At the file descriptor level, stdin is defined to be file descriptor 0, stdout is defined to be file descriptor 1; and stderr is defined to be file descriptor 2. See this. Even if your program -or the shell- changes (e.g. redirect with dup2(2)) what is file descriptor 0, it always stays stdin (since by … Read more
The following statement in your question is wrong: What I know is that a part of the physical memory is reserved to communicate with the hardware A part of the physical memory is not reserved for communication with the hardware. A part of the physical address space, to which the physical memory and memory mapped … Read more
The Linux scheduler (on recent Linux kernels, e.g. 3.0 at least) is scheduling schedulable tasks or simply tasks. A task may be : a single-threaded process (e.g. created by fork without any thread library) any thread inside a multi-threaded process (including its main thread), in particular Posix threads (pthreads) kernel tasks, which are started internally … Read more
‘?’ means that the information about this stack entry is probably not reliable. The stack output mechanism (see the implementation of dump_trace() function) was unable to prove that the address it has found is a valid return address in the call stack. ‘?’ itself is output by printk_stack_address(). The stack entry may be valid or … Read more