Every number on these pages was produced by code that ran on the machine serving this site, not quoted from somewhere else. Each entry publishes the question it answers, the exact method, the hardware it ran on, and the complete source, so you can disagree with the method or run it yourself.
When a process watches many file descriptors and only one becomes ready, how does the cost of noticing it grow with the number of idle descriptors under poll() and under epoll_wait()?
How much throughput does false sharing cost when several threads increment counters that share one cache line, compared with the same counters padded onto separate lines?
On this virtual server, does asking the kernel for 2 MiB transparent huge pages make a dependent random read over a 1 GiB buffer faster than the same buffer on 4 KiB pages, and how much of the buffer actually gets huge pages?
How many random 4 KiB reads per second can one thread sustain with serial pread() syscalls, compared with io_uring submitting 32 at a time, when the page cache is taken out of the picture?
When a program writes to freshly mapped memory, how much does taking one page fault per 4 KiB page cost compared with asking the kernel to populate the whole range in one call before touching it?
On this virtual server, how much slower is reading the monotonic clock through a real system call than through the vDSO, and what does the cheapest possible system call cost?
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