Mirror
/
mergerfs
mirror of https://github.com/trapexit/mergerfs.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
4 Commits
32 Branches
95 Tags
40 MiB
 
 
 
 
Tree: aff371f17f
Branches Tags
${ item.name }
Create tag ${ searchTerm }
Create branch ${ searchTerm }
from 'aff371f17f'
${ noResults }
mergerfs/faq/limit_drive_spinup/index.html

1706 lines
39 KiB
Raw Blame History

<!doctype html>
<html lang="en" class="no-js">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1">
<meta name="description" content="mergerfs - a featureful union filesystem">
<link rel="canonical" href="https://trapexit.github.io/mergerfs/faq/limit_drive_spinup/">
<link rel="prev" href="../technical_behavior_and_limitations/">
<link rel="next" href="../../related_projects/">
<link rel="icon" href="../../assets/images/favicon.png">
<meta name="generator" content="mkdocs-1.6.1, mkdocs-material-9.5.49">
<title>Limiting drive spinup - mergerfs</title>
<link rel="stylesheet" href="../../assets/stylesheets/main.6f8fc17f.min.css">
<link rel="stylesheet" href="../../assets/stylesheets/palette.06af60db.min.css">
<link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Roboto:300,300i,400,400i,700,700i%7CRoboto+Mono:400,400i,700,700i&display=fallback">
<style>:root{--md-text-font:"Roboto";--md-code-font:"Roboto Mono"}</style>
<script>__md_scope=new URL("../..",location),__md_hash=e=>[...e].reduce(((e,_)=>(e<<5)-e+_.charCodeAt(0)),0),__md_get=(e,_=localStorage,t=__md_scope)=>JSON.parse(_.getItem(t.pathname+"."+e)),__md_set=(e,_,t=localStorage,a=__md_scope)=>{try{t.setItem(a.pathname+"."+e,JSON.stringify(_))}catch(e){}}</script>
</head>
<body dir="ltr" data-md-color-scheme="default" data-md-color-primary="indigo" data-md-color-accent="indigo">
<input class="md-toggle" data-md-toggle="drawer" type="checkbox" id="__drawer" autocomplete="off">
<input class="md-toggle" data-md-toggle="search" type="checkbox" id="__search" autocomplete="off">
<label class="md-overlay" for="__drawer"></label>
<div data-md-component="skip">
<a href="#limiting-drive-spinup" class="md-skip">
Skip to content
</a>
</div>
<div data-md-component="announce">
</div>
<header class="md-header md-header--shadow" data-md-component="header">
<nav class="md-header__inner md-grid" aria-label="Header">
<a href="../.." title="mergerfs" class="md-header__button md-logo" aria-label="mergerfs" data-md-component="logo">
<img src="../../logo.jpeg" alt="logo">
</a>
<label class="md-header__button md-icon" for="__drawer">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M3 6h18v2H3zm0 5h18v2H3zm0 5h18v2H3z"/></svg>
</label>
<div class="md-header__title" data-md-component="header-title">
<div class="md-header__ellipsis">
<div class="md-header__topic">
<span class="md-ellipsis">
mergerfs
</span>
</div>
<div class="md-header__topic" data-md-component="header-topic">
<span class="md-ellipsis">
Limiting drive spinup
</span>
</div>
</div>
</div>
<form class="md-header__option" data-md-component="palette">
<input class="md-option" data-md-color-media="(prefers-color-scheme)" data-md-color-scheme="default" data-md-color-primary="indigo" data-md-color-accent="indigo" aria-label="Switch to light mode" type="radio" name="__palette" id="__palette_0">
<label class="md-header__button md-icon" title="Switch to light mode" for="__palette_1" hidden>
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="m14.3 16-.7-2h-3.2l-.7 2H7.8L11 7h2l3.2 9zM20 8.69V4h-4.69L12 .69 8.69 4H4v4.69L.69 12 4 15.31V20h4.69L12 23.31 15.31 20H20v-4.69L23.31 12zm-9.15 3.96h2.3L12 9z"/></svg>
</label>
<input class="md-option" data-md-color-media="(prefers-color-scheme: light)" data-md-color-scheme="default" data-md-color-primary="indigo" data-md-color-accent="indigo" aria-label="Switch to dark mode" type="radio" name="__palette" id="__palette_1">
<label class="md-header__button md-icon" title="Switch to dark mode" for="__palette_2" hidden>
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M12 8a4 4 0 0 0-4 4 4 4 0 0 0 4 4 4 4 0 0 0 4-4 4 4 0 0 0-4-4m0 10a6 6 0 0 1-6-6 6 6 0 0 1 6-6 6 6 0 0 1 6 6 6 6 0 0 1-6 6m8-9.31V4h-4.69L12 .69 8.69 4H4v4.69L.69 12 4 15.31V20h4.69L12 23.31 15.31 20H20v-4.69L23.31 12z"/></svg>
</label>
<input class="md-option" data-md-color-media="(prefers-color-scheme: dark)" data-md-color-scheme="slate" data-md-color-primary="indigo" data-md-color-accent="indigo" aria-label="Switch to system preference" type="radio" name="__palette" id="__palette_2">
<label class="md-header__button md-icon" title="Switch to system preference" for="__palette_0" hidden>
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M12 18c-.89 0-1.74-.2-2.5-.55C11.56 16.5 13 14.42 13 12s-1.44-4.5-3.5-5.45C10.26 6.2 11.11 6 12 6a6 6 0 0 1 6 6 6 6 0 0 1-6 6m8-9.31V4h-4.69L12 .69 8.69 4H4v4.69L.69 12 4 15.31V20h4.69L12 23.31 15.31 20H20v-4.69L23.31 12z"/></svg>
</label>
</form>
<script>var palette=__md_get("__palette");if(palette&&palette.color){if("(prefers-color-scheme)"===palette.color.media){var media=matchMedia("(prefers-color-scheme: light)"),input=document.querySelector(media.matches?"[data-md-color-media='(prefers-color-scheme: light)']":"[data-md-color-media='(prefers-color-scheme: dark)']");palette.color.media=input.getAttribute("data-md-color-media"),palette.color.scheme=input.getAttribute("data-md-color-scheme"),palette.color.primary=input.getAttribute("data-md-color-primary"),palette.color.accent=input.getAttribute("data-md-color-accent")}for(var[key,value]of Object.entries(palette.color))document.body.setAttribute("data-md-color-"+key,value)}</script>
<label class="md-header__button md-icon" for="__search">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M9.5 3A6.5 6.5 0 0 1 16 9.5c0 1.61-.59 3.09-1.56 4.23l.27.27h.79l5 5-1.5 1.5-5-5v-.79l-.27-.27A6.52 6.52 0 0 1 9.5 16 6.5 6.5 0 0 1 3 9.5 6.5 6.5 0 0 1 9.5 3m0 2C7 5 5 7 5 9.5S7 14 9.5 14 14 12 14 9.5 12 5 9.5 5"/></svg>
</label>
<div class="md-search" data-md-component="search" role="dialog">
<label class="md-search__overlay" for="__search"></label>
<div class="md-search__inner" role="search">
<form class="md-search__form" name="search">
<input type="text" class="md-search__input" name="query" aria-label="Search" placeholder="Search" autocapitalize="off" autocorrect="off" autocomplete="off" spellcheck="false" data-md-component="search-query" required>
<label class="md-search__icon md-icon" for="__search">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M9.5 3A6.5 6.5 0 0 1 16 9.5c0 1.61-.59 3.09-1.56 4.23l.27.27h.79l5 5-1.5 1.5-5-5v-.79l-.27-.27A6.52 6.52 0 0 1 9.5 16 6.5 6.5 0 0 1 3 9.5 6.5 6.5 0 0 1 9.5 3m0 2C7 5 5 7 5 9.5S7 14 9.5 14 14 12 14 9.5 12 5 9.5 5"/></svg>
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M20 11v2H8l5.5 5.5-1.42 1.42L4.16 12l7.92-7.92L13.5 5.5 8 11z"/></svg>
</label>
<nav class="md-search__options" aria-label="Search">
<a href="javascript:void(0)" class="md-search__icon md-icon" title="Share" aria-label="Share" data-clipboard data-clipboard-text="" data-md-component="search-share" tabindex="-1">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M18 16.08c-.76 0-1.44.3-1.96.77L8.91 12.7c.05-.23.09-.46.09-.7s-.04-.47-.09-.7l7.05-4.11c.54.5 1.25.81 2.04.81a3 3 0 0 0 3-3 3 3 0 0 0-3-3 3 3 0 0 0-3 3c0 .24.04.47.09.7L8.04 9.81C7.5 9.31 6.79 9 6 9a3 3 0 0 0-3 3 3 3 0 0 0 3 3c.79 0 1.5-.31 2.04-.81l7.12 4.15c-.05.21-.08.43-.08.66 0 1.61 1.31 2.91 2.92 2.91s2.92-1.3 2.92-2.91A2.92 2.92 0 0 0 18 16.08"/></svg>
</a>
<button type="reset" class="md-search__icon md-icon" title="Clear" aria-label="Clear" tabindex="-1">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M19 6.41 17.59 5 12 10.59 6.41 5 5 6.41 10.59 12 5 17.59 6.41 19 12 13.41 17.59 19 19 17.59 13.41 12z"/></svg>
</button>
</nav>
</form>
<div class="md-search__output">
<div class="md-search__scrollwrap" tabindex="0" data-md-scrollfix>
<div class="md-search-result" data-md-component="search-result">
<div class="md-search-result__meta">
Initializing search
</div>
<ol class="md-search-result__list" role="presentation"></ol>
</div>
</div>
</div>
</div>
</div>
<div class="md-header__source">
<a href="https://github.com/trapexit/mergerfs" title="Go to repository" class="md-source" data-md-component="source">
<div class="md-source__icon md-icon">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 448 512"><!--! Font Awesome Free 6.7.1 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2024 Fonticons, Inc.--><path d="M439.55 236.05 244 40.45a28.87 28.87 0 0 0-40.81 0l-40.66 40.63 51.52 51.52c27.06-9.14 52.68 16.77 43.39 43.68l49.66 49.66c34.23-11.8 61.18 31 35.47 56.69-26.49 26.49-70.21-2.87-56-37.34L240.22 199v121.85c25.3 12.54 22.26 41.85 9.08 55a34.34 34.34 0 0 1-48.55 0c-17.57-17.6-11.07-46.91 11.25-56v-123c-20.8-8.51-24.6-30.74-18.64-45L142.57 101 8.45 235.14a28.86 28.86 0 0 0 0 40.81l195.61 195.6a28.86 28.86 0 0 0 40.8 0l194.69-194.69a28.86 28.86 0 0 0 0-40.81"/></svg>
</div>
<div class="md-source__repository">
mergerfs
</div>
</a>
</div>
</nav>
</header>
<div class="md-container" data-md-component="container">
<main class="md-main" data-md-component="main">
<div class="md-main__inner md-grid">
<div class="md-sidebar md-sidebar--primary" data-md-component="sidebar" data-md-type="navigation" >
<div class="md-sidebar__scrollwrap">
<div class="md-sidebar__inner">
<nav class="md-nav md-nav--primary" aria-label="Navigation" data-md-level="0">
<label class="md-nav__title" for="__drawer">
<a href="../.." title="mergerfs" class="md-nav__button md-logo" aria-label="mergerfs" data-md-component="logo">
<img src="../../logo.jpeg" alt="logo">
</a>
mergerfs
</label>
<div class="md-nav__source">
<a href="https://github.com/trapexit/mergerfs" title="Go to repository" class="md-source" data-md-component="source">
<div class="md-source__icon md-icon">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 448 512"><!--! Font Awesome Free 6.7.1 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2024 Fonticons, Inc.--><path d="M439.55 236.05 244 40.45a28.87 28.87 0 0 0-40.81 0l-40.66 40.63 51.52 51.52c27.06-9.14 52.68 16.77 43.39 43.68l49.66 49.66c34.23-11.8 61.18 31 35.47 56.69-26.49 26.49-70.21-2.87-56-37.34L240.22 199v121.85c25.3 12.54 22.26 41.85 9.08 55a34.34 34.34 0 0 1-48.55 0c-17.57-17.6-11.07-46.91 11.25-56v-123c-20.8-8.51-24.6-30.74-18.64-45L142.57 101 8.45 235.14a28.86 28.86 0 0 0 0 40.81l195.61 195.6a28.86 28.86 0 0 0 40.8 0l194.69-194.69a28.86 28.86 0 0 0 0-40.81"/></svg>
</div>
<div class="md-source__repository">
mergerfs
</div>
</a>
</div>
<ul class="md-nav__list" data-md-scrollfix>
<li class="md-nav__item">
<a href="../.." class="md-nav__link">
<span class="md-ellipsis">
Home
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../quickstart/" class="md-nav__link">
<span class="md-ellipsis">
QuickStart
</span>
</a>
</li>
<li class="md-nav__item md-nav__item--nested">
<input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_3" >
<label class="md-nav__link" for="__nav_3" id="__nav_3_label" tabindex="0">
<span class="md-ellipsis">
Installation
</span>
<span class="md-nav__icon md-icon"></span>
</label>
<nav class="md-nav" data-md-level="1" aria-labelledby="__nav_3_label" aria-expanded="false">
<label class="md-nav__title" for="__nav_3">
<span class="md-nav__icon md-icon"></span>
Installation
</label>
<ul class="md-nav__list" data-md-scrollfix>
<li class="md-nav__item">
<a href="../../setup/installation/" class="md-nav__link">
<span class="md-ellipsis">
Installation
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../setup/upgrade/" class="md-nav__link">
<span class="md-ellipsis">
Upgrade
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../setup/build/" class="md-nav__link">
<span class="md-ellipsis">
Build
</span>
</a>
</li>
</ul>
</nav>
</li>
<li class="md-nav__item md-nav__item--nested">
<input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_4" >
<label class="md-nav__link" for="__nav_4" id="__nav_4_label" tabindex="0">
<span class="md-ellipsis">
Config
</span>
<span class="md-nav__icon md-icon"></span>
</label>
<nav class="md-nav" data-md-level="1" aria-labelledby="__nav_4_label" aria-expanded="false">
<label class="md-nav__title" for="__nav_4">
<span class="md-nav__icon md-icon"></span>
Config
</label>
<ul class="md-nav__list" data-md-scrollfix>
<li class="md-nav__item">
<a href="../../config/terminology/" class="md-nav__link">
<span class="md-ellipsis">
Terminology
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/options/" class="md-nav__link">
<span class="md-ellipsis">
Options
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/deprecated_options/" class="md-nav__link">
<span class="md-ellipsis">
Deprecated Options
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/branches/" class="md-nav__link">
<span class="md-ellipsis">
branches
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/functions_categories_and_policies/" class="md-nav__link">
<span class="md-ellipsis">
functions, categories and policies
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/func_readdir/" class="md-nav__link">
<span class="md-ellipsis">
func.readdir
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/rename_and_link/" class="md-nav__link">
<span class="md-ellipsis">
rename and link
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/cache/" class="md-nav__link">
<span class="md-ellipsis">
caching
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/readahead/" class="md-nav__link">
<span class="md-ellipsis">
readahead
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/inodecalc/" class="md-nav__link">
<span class="md-ellipsis">
inodecalc
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/threads/" class="md-nav__link">
<span class="md-ellipsis">
threads
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/pin-threads/" class="md-nav__link">
<span class="md-ellipsis">
pin-threads
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/link_cow/" class="md-nav__link">
<span class="md-ellipsis">
link_cow
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/fuse_msg_size/" class="md-nav__link">
<span class="md-ellipsis">
fuse_msg_size
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/follow-symlinks/" class="md-nav__link">
<span class="md-ellipsis">
follow-symlinks
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/link-exdev/" class="md-nav__link">
<span class="md-ellipsis">
link-exdev
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/rename-exdev/" class="md-nav__link">
<span class="md-ellipsis">
rename-exdev
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/symlinkify/" class="md-nav__link">
<span class="md-ellipsis">
symlinkify
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/nullrw/" class="md-nav__link">
<span class="md-ellipsis">
nullrw
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/xattr/" class="md-nav__link">
<span class="md-ellipsis">
xattr
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/nfsopenhack/" class="md-nav__link">
<span class="md-ellipsis">
nfsopenhack
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/statfs/" class="md-nav__link">
<span class="md-ellipsis">
statfs / statvfs
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/flush-on-close/" class="md-nav__link">
<span class="md-ellipsis">
flush-on-close
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../config/export-support/" class="md-nav__link">
<span class="md-ellipsis">
export-support
</span>
</a>
</li>
</ul>
</nav>
</li>
<li class="md-nav__item">
<a href="../../error_handling/" class="md-nav__link">
<span class="md-ellipsis">
Error Handling
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../runtime_interfaces/" class="md-nav__link">
<span class="md-ellipsis">
Runtime Interfaces
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../remote_filesystems/" class="md-nav__link">
<span class="md-ellipsis">
Remote Filesystems
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../tips_notes/" class="md-nav__link">
<span class="md-ellipsis">
Tips and Notes
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../known_issues_bugs/" class="md-nav__link">
<span class="md-ellipsis">
Known Issues and Bugs
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../project_comparisons/" class="md-nav__link">
<span class="md-ellipsis">
Project Comparisons
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../performance/" class="md-nav__link">
<span class="md-ellipsis">
Tweaking Performance
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../benchmarking/" class="md-nav__link">
<span class="md-ellipsis">
Benchmarking
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../tooling/" class="md-nav__link">
<span class="md-ellipsis">
Tooling
</span>
</a>
</li>
<li class="md-nav__item md-nav__item--active md-nav__item--nested">
<input class="md-nav__toggle md-toggle " type="checkbox" id="__nav_14" checked>
<label class="md-nav__link" for="__nav_14" id="__nav_14_label" tabindex="0">
<span class="md-ellipsis">
FAQ
</span>
<span class="md-nav__icon md-icon"></span>
</label>
<nav class="md-nav" data-md-level="1" aria-labelledby="__nav_14_label" aria-expanded="true">
<label class="md-nav__title" for="__nav_14">
<span class="md-nav__icon md-icon"></span>
FAQ
</label>
<ul class="md-nav__list" data-md-scrollfix>
<li class="md-nav__item">
<a href="../reliability_and_scalability/" class="md-nav__link">
<span class="md-ellipsis">
Reliability and Scalability
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../usage_and_functionality/" class="md-nav__link">
<span class="md-ellipsis">
Usage and Functionality
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../configuration_and_policies/" class="md-nav__link">
<span class="md-ellipsis">
Configuration and Policies
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../compatibility_and_integration/" class="md-nav__link">
<span class="md-ellipsis">
Compatibility and Integration
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../recommendations_and_warnings/" class="md-nav__link">
<span class="md-ellipsis">
Recommendations and Warnings
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../technical_behavior_and_limitations/" class="md-nav__link">
<span class="md-ellipsis">
Technical Behavior and Limitations
</span>
</a>
</li>
<li class="md-nav__item md-nav__item--active">
<input class="md-nav__toggle md-toggle" type="checkbox" id="__toc">
<label class="md-nav__link md-nav__link--active" for="__toc">
<span class="md-ellipsis">
Limiting drive spinup
</span>
<span class="md-nav__icon md-icon"></span>
</label>
<a href="./" class="md-nav__link md-nav__link--active">
<span class="md-ellipsis">
Limiting drive spinup
</span>
</a>
<nav class="md-nav md-nav--secondary" aria-label="Table of contents">
<label class="md-nav__title" for="__toc">
<span class="md-nav__icon md-icon"></span>
Table of contents
</label>
<ul class="md-nav__list" data-md-component="toc" data-md-scrollfix>
<li class="md-nav__item">
<a href="#how-can-i-setup-my-system-to-limit-drive-spinup" class="md-nav__link">
<span class="md-ellipsis">
How can I setup my system to limit drive spinup?
</span>
</a>
<nav class="md-nav" aria-label="How can I setup my system to limit drive spinup?">
<ul class="md-nav__list">
<li class="md-nav__item">
<a href="#what-if-you-assume-no-out-of-band-changes-and-cache-everything" class="md-nav__link">
<span class="md-ellipsis">
What if you assume no out of band changes and cache everything?
</span>
</a>
</li>
<li class="md-nav__item">
<a href="#what-if-you-only-query-already-active-drives" class="md-nav__link">
<span class="md-ellipsis">
What if you only query already active drives?
</span>
</a>
</li>
<li class="md-nav__item">
<a href="#is-there-anything-that-can-be-done-where-mergerfs-is-involved" class="md-nav__link">
<span class="md-ellipsis">
Is there anything that can be done where mergerfs is involved?
</span>
</a>
</li>
</ul>
</nav>
</li>
</ul>
</nav>
</li>
</ul>
</nav>
</li>
<li class="md-nav__item">
<a href="../../related_projects/" class="md-nav__link">
<span class="md-ellipsis">
Related Projects
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../media_and_publicity/" class="md-nav__link">
<span class="md-ellipsis">
Media and Publicity
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../support/" class="md-nav__link">
<span class="md-ellipsis">
Support
</span>
</a>
</li>
<li class="md-nav__item">
<a href="../../sponsorship_and_donations/" class="md-nav__link">
<span class="md-ellipsis">
Sponsorship and Donations
</span>
</a>
</li>
</ul>
</nav>
</div>
</div>
</div>
<div class="md-sidebar md-sidebar--secondary" data-md-component="sidebar" data-md-type="toc" >
<div class="md-sidebar__scrollwrap">
<div class="md-sidebar__inner">
<nav class="md-nav md-nav--secondary" aria-label="Table of contents">
<label class="md-nav__title" for="__toc">
<span class="md-nav__icon md-icon"></span>
Table of contents
</label>
<ul class="md-nav__list" data-md-component="toc" data-md-scrollfix>
<li class="md-nav__item">
<a href="#how-can-i-setup-my-system-to-limit-drive-spinup" class="md-nav__link">
<span class="md-ellipsis">
How can I setup my system to limit drive spinup?
</span>
</a>
<nav class="md-nav" aria-label="How can I setup my system to limit drive spinup?">
<ul class="md-nav__list">
<li class="md-nav__item">
<a href="#what-if-you-assume-no-out-of-band-changes-and-cache-everything" class="md-nav__link">
<span class="md-ellipsis">
What if you assume no out of band changes and cache everything?
</span>
</a>
</li>
<li class="md-nav__item">
<a href="#what-if-you-only-query-already-active-drives" class="md-nav__link">
<span class="md-ellipsis">
What if you only query already active drives?
</span>
</a>
</li>
<li class="md-nav__item">
<a href="#is-there-anything-that-can-be-done-where-mergerfs-is-involved" class="md-nav__link">
<span class="md-ellipsis">
Is there anything that can be done where mergerfs is involved?
</span>
</a>
</li>
</ul>
</nav>
</li>
</ul>
</nav>
</div>
</div>
</div>
<div class="md-content" data-md-component="content">
<article class="md-content__inner md-typeset">
<a href="https://github.com/trapexit/mergerfs/tree/master/mkdocs/docs/faq/limit_drive_spinup.md" title="Edit this page" class="md-content__button md-icon">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M10 20H6V4h7v5h5v3.1l2-2V8l-6-6H6c-1.1 0-2 .9-2 2v16c0 1.1.9 2 2 2h4zm10.2-7c.1 0 .3.1.4.2l1.3 1.3c.2.2.2.6 0 .8l-1 1-2.1-2.1 1-1c.1-.1.2-.2.4-.2m0 3.9L14.1 23H12v-2.1l6.1-6.1z"/></svg>
</a>
<a href="https://github.com/trapexit/mergerfs/tree/master/mkdocs/docs/faq/limit_drive_spinup.md" title="View source of this page" class="md-content__button md-icon">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M17 18c.56 0 1 .44 1 1s-.44 1-1 1-1-.44-1-1 .44-1 1-1m0-3c-2.73 0-5.06 1.66-6 4 .94 2.34 3.27 4 6 4s5.06-1.66 6-4c-.94-2.34-3.27-4-6-4m0 6.5a2.5 2.5 0 0 1-2.5-2.5 2.5 2.5 0 0 1 2.5-2.5 2.5 2.5 0 0 1 2.5 2.5 2.5 2.5 0 0 1-2.5 2.5M9.27 20H6V4h7v5h5v4.07c.7.08 1.36.25 2 .49V8l-6-6H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h4.5a8.2 8.2 0 0 1-1.23-2"/></svg>
</a>
<h1 id="limiting-drive-spinup">Limiting drive spinup</h1>
<h2 id="how-can-i-setup-my-system-to-limit-drive-spinup">How can I setup my system to limit drive spinup?</h2>
<p>TL;DR: You really can't. Not through mergerfs alone.</p>
<p>mergerfs is a proxy. Not a cache. It proxies calls between client software and underlying filesystems. If a client does an <code>open</code>, <code>readdir</code>, <code>stat</code>, etc. it must translate that into something that makes sense across N filesystems. For <code>readdir</code> that means running the call against all branches and aggregating the output. For <code>open</code> that means finding the file to open and doing so. The only way to find the file to open is to scan across all branches and sort the results and pick one. There is no practical way to do otherwise. Especially given so many mergerfs users expect out of band changes to "just work."</p>
<p>The best way to limit spinup of drives is to limit their usage at the client level. Meaning keeping software from interacting with the filesystem all together.</p>
<h3 id="what-if-you-assume-no-out-of-band-changes-and-cache-everything">What if you assume no out of band changes and cache everything?</h3>
<p>This would require a significant rewrite of mergerfs. Everything is done on the fly right now and all those calls to underlying filesystems can cause a spinup. To work around that a database of some sort would have to be used to store ALL metadata about the underlying filesystems and on startup everything scanned and stored. From then on it would have to carefully update all the same data the filesystems do. It couldn't be kept in RAM because it would take up too much space so it'd have to be on a SSD or other storage device. If anything changed out of band it would break things in weird ways. It could rescan on occasion but that would require spinning up everything. It could put file watches on every single directory but that probably won't scale (there are millions of directories in my system for example) and the open files might keep the drives from spinning down. Something as "simple" as keeping the current available free space on each filesystem isn't as easy as one might think given reflinks, snapshots, and other block level dedup technologies.</p>
<p>Even if all metadata (including xattrs) is cached some software will open files (media like videos and audio) to check their metadata. Granted a Plex or Jellyfin scan which may do that is different from a random directory listing but is still something to consider. Those "deep" scans can't be kept from waking drives.</p>
<h3 id="what-if-you-only-query-already-active-drives">What if you only query already active drives?</h3>
<p>Let's assume that is plausible (it isn't because some drives actually will spin up if you ask if they are spun down... yes... really) you would have to either cache all the metadata on the filesystem or treat it like the filesystem doesn't exist. The former has all the problems mentioned prior and the latter would break a lot of things.</p>
<h3 id="is-there-anything-that-can-be-done-where-mergerfs-is-involved">Is there anything that can be done where mergerfs is involved?</h3>
<p>Yes, but whether it works for you depends on your tolerance for the complexity.</p>
<ol>
<li>Cleanly separate writing, storing, and consuming the data.</li>
<li>Use a SSD or dedicated and limited pool of drives for downloads / torrents.</li>
<li>When downloaded move the files to the primary storage pool.</li>
<li>When setting up software like Plex, Jellyfin, etc. point to the underlying filesystems. Not mergerfs.</li>
<li>Add a bunch of bcache, lvmcache, or similar block level cache to your setup. After a bit of use, assuming sufficient storage space, you can limit the likelihood of the underlying spinning disks from needing to be hit.</li>
</ol>
<p>Remember too that while it may be a tradeoff you're willing to live with there is decent evidence that spinning down drives puts increased wear on them and can lead to their death earlier than otherwise.</p>
</article>
</div>
<script>var target=document.getElementById(location.hash.slice(1));target&&target.name&&(target.checked=target.name.startsWith("__tabbed_"))</script>
</div>
<button type="button" class="md-top md-icon" data-md-component="top" hidden>
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M13 20h-2V8l-5.5 5.5-1.42-1.42L12 4.16l7.92 7.92-1.42 1.42L13 8z"/></svg>
Back to top
</button>
</main>
<footer class="md-footer">
<nav class="md-footer__inner md-grid" aria-label="Footer" >
<a href="../technical_behavior_and_limitations/" class="md-footer__link md-footer__link--prev" aria-label="Previous: Technical Behavior and Limitations">
<div class="md-footer__button md-icon">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M20 11v2H8l5.5 5.5-1.42 1.42L4.16 12l7.92-7.92L13.5 5.5 8 11z"/></svg>
</div>
<div class="md-footer__title">
<span class="md-footer__direction">
Previous
</span>
<div class="md-ellipsis">
Technical Behavior and Limitations
</div>
</div>
</a>
<a href="../../related_projects/" class="md-footer__link md-footer__link--next" aria-label="Next: Related Projects">
<div class="md-footer__title">
<span class="md-footer__direction">
Next
</span>
<div class="md-ellipsis">
Related Projects
</div>
</div>
<div class="md-footer__button md-icon">
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M4 11v2h12l-5.5 5.5 1.42 1.42L19.84 12l-7.92-7.92L10.5 5.5 16 11z"/></svg>
</div>
</a>
</nav>
<div class="md-footer-meta md-typeset">
<div class="md-footer-meta__inner md-grid">
<div class="md-copyright">
Made with
<a href="https://squidfunk.github.io/mkdocs-material/" target="_blank" rel="noopener">
Material for MkDocs
</a>
</div>
</div>
</div>
</footer>
</div>
<div class="md-dialog" data-md-component="dialog">
<div class="md-dialog__inner md-typeset"></div>
</div>
<script id="__config" type="application/json">{"base": "../..", "features": ["content.action.edit", "content.action.view", "content.code.copy", "content.code.select", "navigation.footer", "navigation.instant", "navigation.instant.prefetch", "navigation.path", "navigation.top", "navigation.tracking", "optimize", "search.share", "toc.follow"], "search": "../../assets/javascripts/workers/search.6ce7567c.min.js", "translations": {"clipboard.copied": "Copied to clipboard", "clipboard.copy": "Copy to clipboard", "search.result.more.one": "1 more on this page", "search.result.more.other": "# more on this page", "search.result.none": "No matching documents", "search.result.one": "1 matching document", "search.result.other": "# matching documents", "search.result.placeholder": "Type to start searching", "search.result.term.missing": "Missing", "select.version": "Select version"}}</script>
<script src="../../assets/javascripts/bundle.88dd0f4e.min.js"></script>
</body>
</html>