Skip to main content

NFS sync async

NFS Server and Client signification of "sync" and "async"

First, thanks to https://serverfault.com/a/500553

What I write here is basically the same (a copy /paste), but adapted to my personnal needs

sync and async have different meanings for the two different situations.

On the client context

sync in the client context makes all writes to the file be committed to the server. async causes all writes to the file to not be transmitted to the server immediately, usually only when the file is closed. So another host opening the same file is not going to see the changes made by the first host.

Note that NFS offers "close to open" consistency meaning other clients cannot anyway assume that data in a file open by others is consistent (or frankly, that it is consistent at all if you do not use nfslock to add some form of synchronization between clients).

On the server context

sync in the server context (the default) causes the server to only reply to say the data was written when the storage backend actually informs it the data was written. async in the server context gets the server to merely respond as if the file was written on the server irrespective of if it actually has written it. This is a lot faster but also very dangerous as data may have a problem being committed!

Advice

In most cases, async on the client side and sync on the server side. This offers a pretty consistent behaviour with regards to how NFS is supposed to work.

Popular posts from this blog

Undefined global vim

Defining vim as global outside of Neovim When developing plugins for Neovim, particularly in Lua, developers often encounter the "Undefined global vim" warning. This warning can be a nuisance and disrupt the development workflow. However, there is a straightforward solution to this problem by configuring the Lua Language Server Protocol (LSP) to recognize 'vim' as a global variable. Getting "Undefined global vim" warning when developing Neovim plugin While developing Neovim plugins using Lua, the Lua language server might not recognize the 'vim' namespace by default. This leads to warnings about 'vim' being an undefined global variable. These warnings are not just annoying but can also clutter the development environment with unnecessary alerts, potentially hiding other important warnings or errors. Defining vim as global in Lua LSP configuration to get rid of the warning To resolve the "Undefined global vi...

LazyGit AI Commit Message

Having AI‑generated commit messages directly integrated into LazyGit If you use LazyGit every day, you already know how it turns Git from a chore into something you can actually enjoy. But there is one part of the workflow that still tends to feel a bit tedious: writing good commit messages. In this post, I show how to plug OpenAI models directly into LazyGit using a tiny one‑file BASH script, so you can get AI‑generated commit messages based on your actual diffs, without waiting for external tools to catch up with the new OpenAI Responses API . The result is a minimal, focused tool you can drop into your setup today: lgaicm . It behaves like a mini aichat that does exactly one thing: generate commit messages from Git diffs, optimized for LazyGit. Why AI‑generated commit messages in LazyGit? Commit messages matter. They are the stor...

CopilotChat GlobFile Configuration

CopilotChat GlobFile Configuration Want to feed multiple files into GitHub Copilot Chat from Neovim without listing each one manually? Let's add a tiny feature that does exactly that: a file glob that includes full file contents . In this post, we'll walk through what CopilotChat.nvim offers out of the box, why the missing piece matters, and how to implement a custom #file_glob:<pattern> function to include the contents of all files matching a glob. Using Copilot Chat with Neovim CopilotChat.nvim brings GitHub Copilot's chat right into your editing flow. No context switching, no browser hopping — just type your prompt in a Neovim buffer and let the AI help you refactor code, write tests, or explain tricky functions. You can open the chat (for example) with a command like :CopilotChat , then provide extra context using built-in functions. That “extra context” is where the magic really happens. Built-in functio...