To cache rarely accessed pages. It is still better to keep them in swap than paging them out (discarding). But always have enough RAM to hold your expected load. Thorough Perf Tuning Guide https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html-single/performance_tuning_guide/index Reference https://haydenjames.io/linux-performance-almost-always-add-swap-space/ Written with StackEdit.
Introduction mmap maps a file to a process virtual address space. The file blocks are loaded as needed, in units of the system page size. Each I/O must align with the page size. A block load is handled as a page fault. mmap() can provide a private or shared mapping of a region. mmap() to … More Notes on Memory Mapped Files using mmap
How to Install? $ apk –update add postgresql-client How to Login? $ psql -h host_name -d db_name -U user_name Keep the user password ready 🙂 Reference https://gist.github.com/petrkohut/2ed5dc83ca4afd508e9b Written with StackEdit.
Pipe uses kernel buffer to store data. It is a unidirectional read/write buffer and connects two processes. Each end (read or write) Pipe mimics a file operation. A process can choose to read or write (but not both). The processes have to use at least two pipes for two-way communication. Example Communication Parent process can … More One Way Communication with Pipe in Linux
What make Docker so popular and long-lasting? Container is essentially OS level virtualization. Each application gets illusion of its own OS, having almost absolute control over it. Another advantage is that host OS knows about the container processes and hence can share its resources among hosted containers. The concept of containers was started by FreeBSD, … More Why Docker is a Long Term Future for Platform?
Tips to Improve Dynamic Memory Performance Instead of using memset() to initialize malloc()’ed memory, use calloc(). Because when you call memset(), VM system has to map the pages in to memory in order to zero initialize them. It’s very expensive and wasteful if you don’t intend to use the pages right away. calloc() reserves the … More Linux Memory Management Tricks
Problem I upgraded my Ubuntu from 16.04 to 18. And the Internet stopped working. 😦 I tried rebooting interface, adding a new interface to ifconfig. But it did not help. What helped was an answer on AskUbuntu How it worked? The answer is in how Ubuntu lookup domains like http://www.google.com. Step 1 Check the domain … More Internet Not working eh? How Ubuntu Resolves DNS?