{
    "version": "https://jsonfeed.org/version/1.1",
    "user_comment": "This feed allows you to read the posts from this site in any feed reader that supports the JSON Feed format. To add this feed to your reader, copy the following URL -- https://matoken.org/blog/tag/initramfs/feed/json/ -- and add it your reader.",
    "home_page_url": "https://matoken.org/blog/tag/initramfs/",
    "feed_url": "https://matoken.org/blog/tag/initramfs/feed/json/",
    "language": "ja",
    "title": "initramfs – matoken's blog",
    "description": "Is there no plan B?",
    "icon": "https://matoken.org/blog/wp-content/uploads/2025/03/cropped-1865f695c4eecc844385acef2f078255036adccd42c254580ea3844543ab56d9.jpeg",
    "items": [
        {
            "id": "http://matoken.org/blog/?p=3141",
            "url": "https://matoken.org/blog/2021/03/25/change-the-linux-kernel-initramfs-compression-format-on-debian/",
            "title": "Debian \u3067 Linux Kernel \u306e initramfs \u306e\u5727\u7e2e\u5f62\u5f0f\u3092\u5909\u66f4\u3059\u308b\ud83d\udc27\ud83d\udddc\ufe0f",
            "content_html": "<div id=\"preamble\">\n<div class=\"sectionbody\">\n<div class=\"paragraph\">\n<p>\u5148\u65e5\u300c<a href=\"https://matoken.org/blog/2021/03/23/build-linux-kernel-5-11-on-debian-sid/\">Debian sid\u3067Linux Kernel(5.11)\u3092build\u3059\u308b\u30e1\u30e2 </a>\u300d\u3092\u66f8\u3044\u305f\u306e\u3067\u3059\u304c\uff0cTwitter\u3067<a href=\"https://twitter.com/henrich\">@henrich</a>\u3055\u3093\u304b\u3089\u3053\u3093\u306a\u30e1\u30c3\u30bb\u30fc\u30b8\u304c\uff0e</p>\n<blockquote class=\"twitter-tweet\" data-partner=\"tweetdeck\">\n<p lang=\"ja\" dir=\"ltr\">/boot\u306e\u5bb9\u91cf\u306e\u305f\u3081\u306b\u306finitramfs\u306e\u5727\u7e2e\u3092gzip\u304b\u3089xz\u3084zstd\u306b\u3059\u308b\u306e\u3082\u3042\u308a\u3067\u3059\u306d</p>\n<p>\u2014 henrich (@henrich) <a href=\"https://twitter.com/henrich/status/1374350916933935110?ref_src=twsrc%5Etfw\">March 23, 2021</a></p></blockquote>\n<p><script async=\"\" src=\"https://platform.twitter.com/widgets.js\" charset=\"utf-8\"></script></p>\n</div>\n<div class=\"paragraph\">\n<p>\u305d\u3046\u3044\u3048\u3070\u5727\u7e2e\u5f62\u5f0f\u8272\u3005\u3042\u3063\u305f\u306a\u3068\u8a66\u3057\u3066\u307f\u307e\u3057\u305f\uff0e</p>\n</div>\n</div>\n</div>\n<div class=\"sect1\">\n<h2 id=\"_\u73fe\u5728\u306e\u5727\u7e2e\u5f62\u5f0f\u3092\u78ba\u8a8d\u3059\u308b\">\u73fe\u5728\u306e\u5727\u7e2e\u5f62\u5f0f\u3092\u78ba\u8a8d\u3059\u308b</h2>\n<div class=\"sectionbody\">\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ grep COMPRESS /etc/initramfs-tools/initramfs.conf\n# COMPRESS: [ gzip | bzip2 | lz4 | lzma | lzop | xz | zstd ]\nCOMPRESS=gzip</code></pre>\n</div>\n</div>\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ file --mime-type /boot/initrd.img-`uname -r`\n/boot/initrd.img-5.11.8+: application/gzip</code></pre>\n</div>\n</div>\n<div class=\"paragraph\">\n<p>\u8a2d\u5b9a\u306f <code>gzip</code> \u3067\uff0c\u5b9f\u969b\u306e\u30d5\u30a1\u30a4\u30eb\u3082gzip\u306b\u306a\u3063\u3066\u3044\u307e\u3059\uff0e<br />\n\u5727\u7e2e\u5f62\u5f0f\u306f <code>gzip</code> \u4ee5\u5916\u306b <code>bzip2, lz4, lzma, lzop, xz, zstd</code> \u304c\u9078\u3079\u308b\u3088\u3046\u3067\u3059\uff0e</p>\n</div>\n</div>\n</div>\n<div class=\"sect1\">\n<h2 id=\"_\u5727\u7e2e\u5f62\u5f0f\u306e\u6bd4\u8f03\">\u5727\u7e2e\u5f62\u5f0f\u306e\u6bd4\u8f03</h2>\n<div class=\"sectionbody\">\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ ls -1sS --block-size=1 ./initrd.img-5.11.8+.*\n183033856 ./initrd.img-5.11.8+.raw\n 81076224 ./initrd.img-5.11.8+.lz4\n 78315520 ./initrd.img-5.11.8+.lzop\n 54329344 ./initrd.img-5.11.8+.gzip\n 51761152 ./initrd.img-5.11.8+.zstd\n 50081792 ./initrd.img-5.11.8+.bz2\n 36548608 ./initrd.img-5.11.8+.xz\n 36540416 ./initrd.img-5.11.8+.lzma</code></pre>\n</div>\n</div>\n<div class=\"paragraph\">\n<p>\u5bb9\u91cf\u304c\u3069\u306e\u304f\u3089\u3044\u306b\u306a\u308b\u306e\u304b\u5404\u30a2\u30fc\u30ab\u30a4\u30d0\u3067\u5727\u7e2e\u3057\u3066\u307f\u307e\u3057\u305f\uff0e</p>\n</div>\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ \\time -f %e cat ./initrd.img-5.11.8+.raw &gt; /dev/null\n0.03\n$ \\time -f %e lz4cat ./initrd.img-5.11.8+.lz4 &gt; /dev/null\n0.38\n$ \\time -f %e lzop -d -c ./initrd.img-5.11.8+.lzop &gt; /dev/null\n0.42\n$ \\time -f %e zstdcat ./initrd.img-5.11.8+.zstd &gt; /dev/null\n0.44\n$ \\time -f %e zcat ./initrd.img-5.11.8+.gzip &gt; /dev/null\n1.38\n$ \\time -f %e lzma -d -c ./initrd.img-5.11.8+.lzma &gt; /dev/null\n3.22\n$ \\time -f %e xzcat ./initrd.img-5.11.8+.xz &gt; /dev/null\n3.37\n$ \\time -f %e bzcat ./initrd.img-5.11.8+.bz2 &gt; /dev/null\n9.39</code></pre>\n</div>\n</div>\n<div class=\"paragraph\">\n<p>\u5c55\u958b\u6642\u9593\u3082\u78ba\u8a8d\u3057\u3066\u307f\u307e\u3057\u305f\uff0e</p>\n</div>\n<table  class=\"tableblock frame-all grid-all stretch table table-hover\" >\n<colgroup>\n<col style=\"width: 33.3333%;\"/>\n<col style=\"width: 33.3333%;\"/>\n<col style=\"width: 33.3334%;\"/>\n</colgroup>\n<thead>\n<tr>\n<th class=\"tableblock halign-left valign-top\">\u5727\u7e2e\u5f62\u5f0f</th>\n<th class=\"tableblock halign-left valign-top\">\u5727\u7e2e\u30c7\u30fc\u30bf\u91cf(byte)</th>\n<th class=\"tableblock halign-left valign-top\">\u5c55\u958b\u6642\u9593(\u79d2)</th>\n</tr>\n</thead>\n<tbody>\n<tr>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">raw</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">183033856</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">0.03</p>\n</td>\n</tr>\n<tr>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">lz4</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">81076224</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">0.38</p>\n</td>\n</tr>\n<tr>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">lzop</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">78315520</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">0.43</p>\n</td>\n</tr>\n<tr>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">gzip</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">54329344</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">1.38</p>\n</td>\n</tr>\n<tr>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">zstd</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">51761152</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">0.44</p>\n</td>\n</tr>\n<tr>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">bzip2</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">50081792</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">9.39</p>\n</td>\n</tr>\n<tr>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">xz</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">36548608</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">3.37</p>\n</td>\n</tr>\n<tr>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">lzma</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">36540416</p>\n</td>\n<td class=\"tableblock halign-left valign-top\">\n<p class=\"tableblock\">3.22</p>\n</td>\n</tr>\n</tbody>\n</table>\n<div class=\"paragraph\">\n<p>\u5727\u7e2e\u30c7\u30fc\u30bf\u306e\u5727\u7e2e\u7387\u306a\u3069\u306f\u65e2\u5b9a\u5024\u306e\u307e\u307e\u3067\uff0c\u5c55\u958b\u6642\u9593\u306f <code>\\time -f %e zcat ./initrd.img-5.11.8+.gzip &gt; /dev/null</code> \u82e5\u3057\u304f\u306f <code>\\time -f %e lzma -d -c ./initrd.img-5.11.8+.lzma &gt; /dev/null</code> \u306e\u3088\u3046\u306b\u3057\u3066\u6e2c\u308a\u307e\u3057\u305f\uff0e</p>\n</div>\n<div class=\"paragraph\">\n<p>\u30b5\u30a4\u30ba\u3067\u306f raw &gt; lz4 \u2252 lzop &gt; gzip \u2252 zstd \u2252 bz2 &gt; xz \u2252 lzma \u306a\u611f\u3058\u3067\uff0c<br />\n\u5c55\u958b\u901f\u5ea6\u306f bz2 &gt; xz \u2252 lzma &gt; gzip &gt; zstd \u2252 lzop \u2252 lz4 &gt; raw \u306a\u611f\u3058\u3067\u3059\uff0e</p>\n</div>\n<div class=\"admonitionblock caution\">\n<table  class=\" table table-hover\" >\n<tbody>\n<tr>\n<td class=\"icon\">\n<div class=\"title\">Caution</div>\n</td>\n<td class=\"content\">\n\u6642\u9593\u306b\u3064\u3044\u3066\u306f\u30c7\u30b9\u30af\u30c8\u30c3\u30d7\u74b0\u5883\u3067\u8272\u3005\u52d5\u3044\u3066\u3044\u308b\u72b6\u614b\u30671\u56de\u3057\u304b\u6e2c\u3063\u3066\u3044\u306a\u3044\u306e\u3067\u76ee\u5b89\u7a0b\u5ea6\u306b\u3057\u3066\u304f\u3060\u3055\u3044\uff0e</td>\n</tr>\n</tbody>\n</table>\n</div>\n<div class=\"admonitionblock caution\">\n<table  class=\" table table-hover\" >\n<tbody>\n<tr>\n<td class=\"icon\">\n<div class=\"title\">Caution</div>\n</td>\n<td class=\"content\">\n\u3053\u3053\u3067\u306f\u65e2\u5b9a\u5024\u3067\u5727\u7e2e\u3057\u307e\u3057\u305f\u304c\uff0czstd, lz4, xz\u306b\u3064\u3044\u3066\u306finitramfs\u4f5c\u6210\u6642\u306b\u5727\u7e2e\u30aa\u30d7\u30b7\u30e7\u30f3\u306a\u3069\u304c\u65e2\u5b9a\u5024\u3068\u9055\u3046\u3088\u3046\u306a\u306e\u3067\u76ee\u5b89\u7a0b\u5ea6\u306b\u3057\u3066\u304f\u3060\u3055\u3044\uff0e</td>\n</tr>\n</tbody>\n</table>\n</div>\n<div class=\"paragraph\">\n<p>\u5bb9\u91cf\u7684\u306b\u306fxz, lzma\u304c\u826f\u3055\u305d\u3046\u3067\u3059\u304c\u5c55\u958b\u6642\u9593\u304c\u3068\u3066\u3082\u5897\u3048\u305d\u3046\u3067\u3059\uff0ezstd\u306fgzip\u3088\u308a\u901f\u304f\u3066\u5c0f\u3055\u304f\u306a\u3063\u3066\u826f\u3055\u305d\u3046\u3067\u3059\uff0e<br />\n\u3068\u3044\u3046\u3053\u3068\u3067zstd\u306b\u3057\u3066\u307f\u307e\u3059\uff0e</p>\n</div>\n</div>\n</div>\n<div class=\"sect1\">\n<h2 id=\"_initramfs\u3092_zstd_\u3067\u4f5c\u308a\u76f4\u3059\">initramfs\u3092 zstd \u3067\u4f5c\u308a\u76f4\u3059</h2>\n<div class=\"sectionbody\">\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ sudo git -C /etc diff HEAD /etc/initramfs-tools/initramfs.conf\ndiff --git a/initramfs-tools/initramfs.conf b/initramfs-tools/initramfs.conf\nindex 01bdd85..a0c051b 100644\n--- a/initramfs-tools/initramfs.conf\n+++ b/initramfs-tools/initramfs.conf\n@@ -41,7 +41,7 @@ KEYMAP=n\n # COMPRESS: [ gzip | bzip2 | lz4 | lzma | lzop | xz | zstd ]\n #\n\n-COMPRESS=gzip\n+COMPRESS=zstd\n\n #\n # DEVICE: ...</code></pre>\n</div>\n</div>\n<div class=\"paragraph\">\n<p><code>/etc/initramfs-tools/initramfs.conf</code> \u3092\u7de8\u96c6\u3057\u3066\uff0c <code>COMPRESS</code> \u3092 <code>zstd</code> \u306b\u5909\u66f4\u3057\u307e\u3059\uff0e</p>\n</div>\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ update-initramfs -h\n\nUsage: update-initramfs {-c|-d|-u} [-k version] [-v] [-b directory]\n\nOptions:\n -k version     Specify kernel version or 'all'\n -c             Create a new initramfs\n -u             Update an existing initramfs\n -d             Remove an existing initramfs\n -b directory   Set alternate boot directory\n -v             Be verbose\n\nSee update-initramfs(8) for further details.\n\n$ sudo update-initramfs -k `uname -r` -u -v</code></pre>\n</div>\n</div>\n<div class=\"paragraph\">\n<p><code>update-initramfs</code> \u3067\u66f4\u65b0\u3092\u884c\u3044\u307e\u3059\uff0e</p>\n</div>\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ ls -s --block-size=1 /boot/initrd.img-5.11.8+\n54542336 /boot/initrd.img-5.11.8+\n$ ls -s --block-size=1 /boot/initrd.img-5.11.8+\n41611264 /boot/initrd.img-5.11.8+\n$ file --mime-type /boot/initrd.img-5.11.8+\n/boot/initrd.img-5.11.8+: application/zstd\n$ zstd -lv /boot/initrd.img-5.11.8+\n*** zstd command line interface 64-bits v1.4.8, by Yann Collet ***\n/boot/initrd.img-5.11.8+\n# Zstandard Frames: 1\nWindow Size: 8.00 MB (8388608 B)\nCompressed Size: 39.53 MB (41446437 B)\nDecompressed Size: 174.55 MB (183032320 B)\nRatio: 4.4161\nCheck: XXH64</code></pre>\n</div>\n</div>\n<div class=\"paragraph\">\n<p>\u51fa\u6765\u4e0a\u304c\u3063\u305f\u30d5\u30a1\u30a4\u30eb\u3092\u78ba\u8a8d\u3059\u308b\u3068 <code>zstd</code> \u306b\u306a\u3063\u3066\u3044\u307e\u3057\u305f\uff0e<br />\n\u518d\u8d77\u52d5\u3057\u3066\u3082\u554f\u984c\u3042\u308a\u307e\u305b\u3093\u3067\u3057\u305f :)<br />\n\u4e0a\u3067\u78ba\u8a8d\u3057\u305f\u5bb9\u91cf\u3088\u308a\u5927\u5206\u5c0f\u3055\u5538\u3063\u3066\u3044\u308b\u306e\u306f\u5727\u7e2e\u30ec\u30d9\u30eb\u306e\u5dee\u3067\u3057\u3087\u3046\u304b?</p>\n</div>\n</div>\n</div>\n<div class=\"sect1\">\n<h2 id=\"_initramfs\u5727\u7e2e\u30ec\u30d9\u30eb\u306e\u78ba\u8a8d\">initramfs\u5727\u7e2e\u30ec\u30d9\u30eb\u306e\u78ba\u8a8d</h2>\n<div class=\"sectionbody\">\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ grep zstd /usr/sbin/mkinitramfs\nzstd)   compress=\"zstd -q -19 -T0\" ;;</code></pre>\n</div>\n</div>\n<div class=\"paragraph\">\n<p><code>update-initramfs</code> \u304b\u3089\u547c\u3070\u308c\u308b <code>mkinitramfs</code> \u3092\u78ba\u8a8d\u3059\u308b\u3068zstd\u306e\u5727\u7e2e\u30ec\u30d9\u30eb\u30aa\u30d7\u30b7\u30e7\u30f3\u306f <code>-19</code> \u3067\u6700\u9ad8\u5727\u7e2e\u7387\u3067\u3057\u305f\uff0e(\u65e2\u5b9a\u5024\u306f <code>-3</code> )</p>\n</div>\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ \\time -f%e zstdcat -T1 /boot/initrd.img-5.11.8+ &gt; /dev/null\n0.50</code></pre>\n</div>\n</div>\n<div class=\"paragraph\">\n<p>\u305d\u306e\u5206\u5c55\u958b\u6642\u9593\u3082\u5c11\u3057\u4f38\u3073\u3066\u3044\u305d\u3046\u3067\u3059\uff0e</p>\n</div>\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">case \"${compress}\" in\ngzip)   # If we're doing a reproducible build, use gzip -n\n        if [ -n \"${SOURCE_DATE_EPOCH}\" ]; then\n                compress=\"gzip -n\"\n        # Otherwise, substitute pigz if it's available\n        elif command -v pigz &gt;/dev/null; then\n                compress=pigz\n        fi\n        ;;\nlz4)    compress=\"lz4 -9 -l\" ;;\nzstd)   compress=\"zstd -q -19 -T0\" ;;\nxz)     compress=\"xz --check=crc32\"\n        # If we're not doing a reproducible build, enable multithreading\n        test -z \"${SOURCE_DATE_EPOCH}\" &amp;&amp; compress=\"$compress --threads=0\"\n        ;;\nbzip2|lzma|lzop)\n        # no parameters needed\n        ;;\n*)      echo \"W: Unknown compression command ${compress}\" &gt;&amp;2 ;;\nesac</code></pre>\n</div>\n</div>\n<div class=\"paragraph\">\n<p>\u5468\u308a\u3092\u898b\u3066\u307f\u308b\u3068\uff0c <code>lz4</code> \u306f <code>-9</code> \u3067\u6700\u9ad8( <code>-12</code> )\u3067\u306f\u306a\u3044\u3051\u3069\u65e2\u5b9a\u5024( <code>1</code> )\u3088\u308a\u5727\u7e2e\u7387\u3092\u9ad8\u304f\u3057\u3066\u3042\u308a\u307e\u3059\uff0exz\u306b\u306f\u6574\u5408\u6027\u30c1\u30a7\u30c3\u30af\u304c\u30aa\u30d7\u30b7\u30e7\u30f3\u304c\u3042\u308b\u3051\u3069\u5bb9\u91cf\u306b\u306f\u3042\u307e\u308a\u95a2\u4fc2\u306a\u3044\u304b\u306a?<br />\n\u305d\u306e\u4ed6\u306f\u65e2\u5b9a\u5024\u306e\u3088\u3046\u3067\u3059\uff0e</p>\n</div>\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ count=1;while [[ $count -lt 19 ]];do zstdcat /boot/initrd.img-5.11.8+ | zstd -T0 -$count -c - &gt; /tmp/zstd-$count.zstd;count=$(( $count+1 ));done\n$ ls -1sS --block-size=1 /tmp/zstd-*\n56188928 /tmp/zstd-1.zstd\n53272576 /tmp/zstd-2.zstd\n51761152 /tmp/zstd-3.zstd\n51466240 /tmp/zstd-4.zstd\n50061312 /tmp/zstd-5.zstd\n49614848 /tmp/zstd-6.zstd\n47431680 /tmp/zstd-7.zstd\n46690304 /tmp/zstd-8.zstd\n46424064 /tmp/zstd-9.zstd\n45973504 /tmp/zstd-10.zstd\n45850624 /tmp/zstd-11.zstd\n45686784 /tmp/zstd-12.zstd\n45539328 /tmp/zstd-13.zstd\n45371392 /tmp/zstd-14.zstd\n45309952 /tmp/zstd-15.zstd\n44093440 /tmp/zstd-16.zstd\n42987520 /tmp/zstd-17.zstd\n41705472 /tmp/zstd-18.zstd\n41447424 /tmp/zstd-19.zstd\n$ ls -1S /tmp/zstd-* | xargs -I{} -n1 sh -c \"echo -n \\\"{} \\\"; \\time -f%e zstdcat -T0 {} &gt; /dev/null\"\n/tmp/zstd-1.zstd 0.37\n/tmp/zstd-2.zstd 0.36\n/tmp/zstd-3.zstd 0.40\n/tmp/zstd-4.zstd 0.47\n/tmp/zstd-5.zstd 0.44\n/tmp/zstd-6.zstd 0.42\n/tmp/zstd-7.zstd 0.40\n/tmp/zstd-8.zstd 0.37\n/tmp/zstd-9.zstd 0.35\n/tmp/zstd-10.zstd 0.40\n/tmp/zstd-11.zstd 0.41\n/tmp/zstd-12.zstd 0.38\n/tmp/zstd-13.zstd 0.39\n/tmp/zstd-14.zstd 0.39\n/tmp/zstd-15.zstd 0.43\n/tmp/zstd-16.zstd 0.37\n/tmp/zstd-17.zstd 0.42\n/tmp/zstd-18.zstd 0.53\n/tmp/zstd-19.zstd 0.68</code></pre>\n</div>\n</div>\n<div class=\"paragraph\">\n<p>\u5727\u7e2e\u30ec\u30d9\u30eb\u3054\u3068\u306e\u5bb9\u91cf\u3068\u5c55\u958b\u6642\u9593\u306f\u3053\u3093\u306a\u611f\u3058\u306b\u306a\u308a\u307e\u3057\u305f\uff0e\u8272\u3005\u52d5\u3044\u3066\u3044\u308b\u74b0\u5883\u306a\u306e\u3067\u304a\u304b\u3057\u305d\u3046\u306a\u3068\u3053\u308d\u304c\u3042\u308a\u307e\u3059\u304c\u5927\u4f53\u306e\u76ee\u5b89\u3068\u3057\u3066\uff0e</p>\n</div>\n</div>\n</div>\n<div class=\"sect1\">\n<h2 id=\"_kernel_build\u6642\u306e\u52d5\u4f5c\">Kernel build\u6642\u306e\u52d5\u4f5c</h2>\n<div class=\"sectionbody\">\n<div class=\"paragraph\">\n<p>Kernel 5.11.9 \u304c\u6765\u3066\u3044\u305f\u306e\u3067\u30d3\u30eb\u30c9\u3057\u3066\u307f\u307e\u3057\u305f\uff0e</p>\n</div>\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ wget https://cdn.kernel.org/pub/linux/kernel/v5.x/incr/patch-5.11.8-9.xz\n$ cd linux-5.11\n$ xzcat ../patch-5.11.8-9.xz | patch -p1\n$ grep ^COMPRESS= /etc/initramfs-tools/initramfs.conf\nCOMPRESS=zstd\n$ time make -j`nproc` bindeb-pkg\n$ ls -1sS ../*5.11.9*\n737300 ../linux-image-5.11.9+-dbg_5.11.9+-5_amd64.deb\n 59584 ../linux-image-5.11.9+_5.11.9+-5_amd64.deb\n  8040 ../linux-headers-5.11.9+_5.11.9+-5_amd64.deb\n  1124 ../linux-libc-dev_5.11.9+-5_amd64.deb\n     8 ../linux-5.11.9+_5.11.9+-5_amd64.buildinfo\n     4 ../linux-5.11.9+_5.11.9+-5_amd64.changes\n$ sudo apt install ../linux-image-5.11.9+_5.11.9+-5_amd64.deb ../linux-headers-5.11.9+_5.11.9+-5_amd64.deb ../linux\n-libc-dev_5.11.9+-5_amd64.deb\n$ file /boot/initrd.img-5.11.9+\n/boot/initrd.img-5.11.9+: Zstandard compressed data (v0.8+), Dictionary ID: None\n$ ls --block-size=1 -s /boot/initrd.img-5.11.9+\n41602048 /boot/initrd.img-5.11.9+\n$ sudo shutdown -r now 'kernel upgrade'</code></pre>\n</div>\n</div>\n<div class=\"paragraph\">\n<p>\u554f\u984c\u306a\u304f zstd \u306b\u306a\u308a\u307e\u3057\u305f\uff0e</p>\n</div>\n</div>\n</div>\n<div class=\"sect1\">\n<h2 id=\"_\u53c2\u8003url\">\u53c2\u8003URL</h2>\n<div class=\"sectionbody\">\n<div class=\"paragraph\">\n<p>Debian\u306einitramfs\u306e\u5727\u7e2e\u5f62\u5f0f\u3092zstd\u306b\u3057\u3088\u3046\u3068\u3044\u3046\u30d0\u30b0\u30ec\u30dd\u30fc\u30c8\uff0ebullseye\u306f\u30d5\u30ea\u30fc\u30ba\u3055\u308c\u3066\u3044\u308b\u306e\u3067\u5165\u3089\u306a\u3044\uff0e</p>\n</div>\n<div class=\"ulist\">\n<ul>\n<li><a href=\"https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=976054\">#976054 &#8211; initramfs-tools: [RFC] Compress initramfs file with zstd &#8211; Debian Bug report logs</a></li>\n</ul>\n</div>\n</div>\n</div>\n<div class=\"sect1\">\n<h2 id=\"_\u74b0\u5883\">\u74b0\u5883</h2>\n<div class=\"sectionbody\">\n<div class=\"listingblock\">\n<div class=\"content\">\n<pre class=\"highlight\"><code class=\"language-shell\" data-lang=\"shell\">$ dpkg-query -W initramfs-tools-core zstd\ninitramfs-tools-core    0.140\nzstd    1.4.8+dfsg-2.1\n$ lsb_release -dr\nDescription:    Debian GNU/Linux bullseye/sid\nRelease:        unstable\n$ uname -srm\nLinux 5.11.9+ x86_64</code></pre>\n</div>\n</div>\n</div>\n</div>\n",
            "content_text": "\u5148\u65e5\u300cDebian sid\u3067Linux Kernel(5.11)\u3092build\u3059\u308b\u30e1\u30e2 \u300d\u3092\u66f8\u3044\u305f\u306e\u3067\u3059\u304c\uff0cTwitter\u3067@henrich\u3055\u3093\u304b\u3089\u3053\u3093\u306a\u30e1\u30c3\u30bb\u30fc\u30b8\u304c\uff0e\n\n/boot\u306e\u5bb9\u91cf\u306e\u305f\u3081\u306b\u306finitramfs\u306e\u5727\u7e2e\u3092gzip\u304b\u3089xz\u3084zstd\u306b\u3059\u308b\u306e\u3082\u3042\u308a\u3067\u3059\u306d\n\u2014 henrich (@henrich) March 23, 2021\n\n\n\n\u305d\u3046\u3044\u3048\u3070\u5727\u7e2e\u5f62\u5f0f\u8272\u3005\u3042\u3063\u305f\u306a\u3068\u8a66\u3057\u3066\u307f\u307e\u3057\u305f\uff0e\n\n\n\n\n\u73fe\u5728\u306e\u5727\u7e2e\u5f62\u5f0f\u3092\u78ba\u8a8d\u3059\u308b\n\n\n\n$ grep COMPRESS /etc/initramfs-tools/initramfs.conf\n# COMPRESS: [ gzip | bzip2 | lz4 | lzma | lzop | xz | zstd ]\nCOMPRESS=gzip\n\n\n\n\n$ file --mime-type /boot/initrd.img-`uname -r`\n/boot/initrd.img-5.11.8+: application/gzip\n\n\n\n\u8a2d\u5b9a\u306f gzip \u3067\uff0c\u5b9f\u969b\u306e\u30d5\u30a1\u30a4\u30eb\u3082gzip\u306b\u306a\u3063\u3066\u3044\u307e\u3059\uff0e\n\u5727\u7e2e\u5f62\u5f0f\u306f gzip \u4ee5\u5916\u306b bzip2, lz4, lzma, lzop, xz, zstd \u304c\u9078\u3079\u308b\u3088\u3046\u3067\u3059\uff0e\n\n\n\n\n\u5727\u7e2e\u5f62\u5f0f\u306e\u6bd4\u8f03\n\n\n\n$ ls -1sS --block-size=1 ./initrd.img-5.11.8+.*\n183033856 ./initrd.img-5.11.8+.raw\n 81076224 ./initrd.img-5.11.8+.lz4\n 78315520 ./initrd.img-5.11.8+.lzop\n 54329344 ./initrd.img-5.11.8+.gzip\n 51761152 ./initrd.img-5.11.8+.zstd\n 50081792 ./initrd.img-5.11.8+.bz2\n 36548608 ./initrd.img-5.11.8+.xz\n 36540416 ./initrd.img-5.11.8+.lzma\n\n\n\n\u5bb9\u91cf\u304c\u3069\u306e\u304f\u3089\u3044\u306b\u306a\u308b\u306e\u304b\u5404\u30a2\u30fc\u30ab\u30a4\u30d0\u3067\u5727\u7e2e\u3057\u3066\u307f\u307e\u3057\u305f\uff0e\n\n\n\n$ \\time -f %e cat ./initrd.img-5.11.8+.raw &gt; /dev/null\n0.03\n$ \\time -f %e lz4cat ./initrd.img-5.11.8+.lz4 &gt; /dev/null\n0.38\n$ \\time -f %e lzop -d -c ./initrd.img-5.11.8+.lzop &gt; /dev/null\n0.42\n$ \\time -f %e zstdcat ./initrd.img-5.11.8+.zstd &gt; /dev/null\n0.44\n$ \\time -f %e zcat ./initrd.img-5.11.8+.gzip &gt; /dev/null\n1.38\n$ \\time -f %e lzma -d -c ./initrd.img-5.11.8+.lzma &gt; /dev/null\n3.22\n$ \\time -f %e xzcat ./initrd.img-5.11.8+.xz &gt; /dev/null\n3.37\n$ \\time -f %e bzcat ./initrd.img-5.11.8+.bz2 &gt; /dev/null\n9.39\n\n\n\n\u5c55\u958b\u6642\u9593\u3082\u78ba\u8a8d\u3057\u3066\u307f\u307e\u3057\u305f\uff0e\n\n\n\n\n\n\n\n\n\n\u5727\u7e2e\u5f62\u5f0f\n\u5727\u7e2e\u30c7\u30fc\u30bf\u91cf(byte)\n\u5c55\u958b\u6642\u9593(\u79d2)\n\n\n\n\n\nraw\n\n\n183033856\n\n\n0.03\n\n\n\n\nlz4\n\n\n81076224\n\n\n0.38\n\n\n\n\nlzop\n\n\n78315520\n\n\n0.43\n\n\n\n\ngzip\n\n\n54329344\n\n\n1.38\n\n\n\n\nzstd\n\n\n51761152\n\n\n0.44\n\n\n\n\nbzip2\n\n\n50081792\n\n\n9.39\n\n\n\n\nxz\n\n\n36548608\n\n\n3.37\n\n\n\n\nlzma\n\n\n36540416\n\n\n3.22\n\n\n\n\n\n\u5727\u7e2e\u30c7\u30fc\u30bf\u306e\u5727\u7e2e\u7387\u306a\u3069\u306f\u65e2\u5b9a\u5024\u306e\u307e\u307e\u3067\uff0c\u5c55\u958b\u6642\u9593\u306f \\time -f %e zcat ./initrd.img-5.11.8+.gzip &gt; /dev/null \u82e5\u3057\u304f\u306f \\time -f %e lzma -d -c ./initrd.img-5.11.8+.lzma &gt; /dev/null \u306e\u3088\u3046\u306b\u3057\u3066\u6e2c\u308a\u307e\u3057\u305f\uff0e\n\n\n\u30b5\u30a4\u30ba\u3067\u306f raw &gt; lz4 \u2252 lzop &gt; gzip \u2252 zstd \u2252 bz2 &gt; xz \u2252 lzma \u306a\u611f\u3058\u3067\uff0c\n\u5c55\u958b\u901f\u5ea6\u306f bz2 &gt; xz \u2252 lzma &gt; gzip &gt; zstd \u2252 lzop \u2252 lz4 &gt; raw \u306a\u611f\u3058\u3067\u3059\uff0e\n\n\n\n\n\n\nCaution\n\n\n\u6642\u9593\u306b\u3064\u3044\u3066\u306f\u30c7\u30b9\u30af\u30c8\u30c3\u30d7\u74b0\u5883\u3067\u8272\u3005\u52d5\u3044\u3066\u3044\u308b\u72b6\u614b\u30671\u56de\u3057\u304b\u6e2c\u3063\u3066\u3044\u306a\u3044\u306e\u3067\u76ee\u5b89\u7a0b\u5ea6\u306b\u3057\u3066\u304f\u3060\u3055\u3044\uff0e\n\n\n\n\n\n\n\n\n\nCaution\n\n\n\u3053\u3053\u3067\u306f\u65e2\u5b9a\u5024\u3067\u5727\u7e2e\u3057\u307e\u3057\u305f\u304c\uff0czstd, lz4, xz\u306b\u3064\u3044\u3066\u306finitramfs\u4f5c\u6210\u6642\u306b\u5727\u7e2e\u30aa\u30d7\u30b7\u30e7\u30f3\u306a\u3069\u304c\u65e2\u5b9a\u5024\u3068\u9055\u3046\u3088\u3046\u306a\u306e\u3067\u76ee\u5b89\u7a0b\u5ea6\u306b\u3057\u3066\u304f\u3060\u3055\u3044\uff0e\n\n\n\n\n\n\u5bb9\u91cf\u7684\u306b\u306fxz, lzma\u304c\u826f\u3055\u305d\u3046\u3067\u3059\u304c\u5c55\u958b\u6642\u9593\u304c\u3068\u3066\u3082\u5897\u3048\u305d\u3046\u3067\u3059\uff0ezstd\u306fgzip\u3088\u308a\u901f\u304f\u3066\u5c0f\u3055\u304f\u306a\u3063\u3066\u826f\u3055\u305d\u3046\u3067\u3059\uff0e\n\u3068\u3044\u3046\u3053\u3068\u3067zstd\u306b\u3057\u3066\u307f\u307e\u3059\uff0e\n\n\n\n\ninitramfs\u3092 zstd \u3067\u4f5c\u308a\u76f4\u3059\n\n\n\n$ sudo git -C /etc diff HEAD /etc/initramfs-tools/initramfs.conf\ndiff --git a/initramfs-tools/initramfs.conf b/initramfs-tools/initramfs.conf\nindex 01bdd85..a0c051b 100644\n--- a/initramfs-tools/initramfs.conf\n+++ b/initramfs-tools/initramfs.conf\n@@ -41,7 +41,7 @@ KEYMAP=n\n # COMPRESS: [ gzip | bzip2 | lz4 | lzma | lzop | xz | zstd ]\n #\n\n-COMPRESS=gzip\n+COMPRESS=zstd\n\n #\n # DEVICE: ...\n\n\n\n/etc/initramfs-tools/initramfs.conf \u3092\u7de8\u96c6\u3057\u3066\uff0c COMPRESS \u3092 zstd \u306b\u5909\u66f4\u3057\u307e\u3059\uff0e\n\n\n\n$ update-initramfs -h\n\nUsage: update-initramfs {-c|-d|-u} [-k version] [-v] [-b directory]\n\nOptions:\n -k version     Specify kernel version or 'all'\n -c             Create a new initramfs\n -u             Update an existing initramfs\n -d             Remove an existing initramfs\n -b directory   Set alternate boot directory\n -v             Be verbose\n\nSee update-initramfs(8) for further details.\n\n$ sudo update-initramfs -k `uname -r` -u -v\n\n\n\nupdate-initramfs \u3067\u66f4\u65b0\u3092\u884c\u3044\u307e\u3059\uff0e\n\n\n\n$ ls -s --block-size=1 /boot/initrd.img-5.11.8+\n54542336 /boot/initrd.img-5.11.8+\n$ ls -s --block-size=1 /boot/initrd.img-5.11.8+\n41611264 /boot/initrd.img-5.11.8+\n$ file --mime-type /boot/initrd.img-5.11.8+\n/boot/initrd.img-5.11.8+: application/zstd\n$ zstd -lv /boot/initrd.img-5.11.8+\n*** zstd command line interface 64-bits v1.4.8, by Yann Collet ***\n/boot/initrd.img-5.11.8+\n# Zstandard Frames: 1\nWindow Size: 8.00 MB (8388608 B)\nCompressed Size: 39.53 MB (41446437 B)\nDecompressed Size: 174.55 MB (183032320 B)\nRatio: 4.4161\nCheck: XXH64\n\n\n\n\u51fa\u6765\u4e0a\u304c\u3063\u305f\u30d5\u30a1\u30a4\u30eb\u3092\u78ba\u8a8d\u3059\u308b\u3068 zstd \u306b\u306a\u3063\u3066\u3044\u307e\u3057\u305f\uff0e\n\u518d\u8d77\u52d5\u3057\u3066\u3082\u554f\u984c\u3042\u308a\u307e\u305b\u3093\u3067\u3057\u305f :)\n\u4e0a\u3067\u78ba\u8a8d\u3057\u305f\u5bb9\u91cf\u3088\u308a\u5927\u5206\u5c0f\u3055\u5538\u3063\u3066\u3044\u308b\u306e\u306f\u5727\u7e2e\u30ec\u30d9\u30eb\u306e\u5dee\u3067\u3057\u3087\u3046\u304b?\n\n\n\n\ninitramfs\u5727\u7e2e\u30ec\u30d9\u30eb\u306e\u78ba\u8a8d\n\n\n\n$ grep zstd /usr/sbin/mkinitramfs\nzstd)   compress=\"zstd -q -19 -T0\" ;;\n\n\n\nupdate-initramfs \u304b\u3089\u547c\u3070\u308c\u308b mkinitramfs \u3092\u78ba\u8a8d\u3059\u308b\u3068zstd\u306e\u5727\u7e2e\u30ec\u30d9\u30eb\u30aa\u30d7\u30b7\u30e7\u30f3\u306f -19 \u3067\u6700\u9ad8\u5727\u7e2e\u7387\u3067\u3057\u305f\uff0e(\u65e2\u5b9a\u5024\u306f -3 )\n\n\n\n$ \\time -f%e zstdcat -T1 /boot/initrd.img-5.11.8+ &gt; /dev/null\n0.50\n\n\n\n\u305d\u306e\u5206\u5c55\u958b\u6642\u9593\u3082\u5c11\u3057\u4f38\u3073\u3066\u3044\u305d\u3046\u3067\u3059\uff0e\n\n\n\ncase \"${compress}\" in\ngzip)   # If we're doing a reproducible build, use gzip -n\n        if [ -n \"${SOURCE_DATE_EPOCH}\" ]; then\n                compress=\"gzip -n\"\n        # Otherwise, substitute pigz if it's available\n        elif command -v pigz &gt;/dev/null; then\n                compress=pigz\n        fi\n        ;;\nlz4)    compress=\"lz4 -9 -l\" ;;\nzstd)   compress=\"zstd -q -19 -T0\" ;;\nxz)     compress=\"xz --check=crc32\"\n        # If we're not doing a reproducible build, enable multithreading\n        test -z \"${SOURCE_DATE_EPOCH}\" &amp;&amp; compress=\"$compress --threads=0\"\n        ;;\nbzip2|lzma|lzop)\n        # no parameters needed\n        ;;\n*)      echo \"W: Unknown compression command ${compress}\" &gt;&amp;2 ;;\nesac\n\n\n\n\u5468\u308a\u3092\u898b\u3066\u307f\u308b\u3068\uff0c lz4 \u306f -9 \u3067\u6700\u9ad8( -12 )\u3067\u306f\u306a\u3044\u3051\u3069\u65e2\u5b9a\u5024( 1 )\u3088\u308a\u5727\u7e2e\u7387\u3092\u9ad8\u304f\u3057\u3066\u3042\u308a\u307e\u3059\uff0exz\u306b\u306f\u6574\u5408\u6027\u30c1\u30a7\u30c3\u30af\u304c\u30aa\u30d7\u30b7\u30e7\u30f3\u304c\u3042\u308b\u3051\u3069\u5bb9\u91cf\u306b\u306f\u3042\u307e\u308a\u95a2\u4fc2\u306a\u3044\u304b\u306a?\n\u305d\u306e\u4ed6\u306f\u65e2\u5b9a\u5024\u306e\u3088\u3046\u3067\u3059\uff0e\n\n\n\n$ count=1;while [[ $count -lt 19 ]];do zstdcat /boot/initrd.img-5.11.8+ | zstd -T0 -$count -c - &gt; /tmp/zstd-$count.zstd;count=$(( $count+1 ));done\n$ ls -1sS --block-size=1 /tmp/zstd-*\n56188928 /tmp/zstd-1.zstd\n53272576 /tmp/zstd-2.zstd\n51761152 /tmp/zstd-3.zstd\n51466240 /tmp/zstd-4.zstd\n50061312 /tmp/zstd-5.zstd\n49614848 /tmp/zstd-6.zstd\n47431680 /tmp/zstd-7.zstd\n46690304 /tmp/zstd-8.zstd\n46424064 /tmp/zstd-9.zstd\n45973504 /tmp/zstd-10.zstd\n45850624 /tmp/zstd-11.zstd\n45686784 /tmp/zstd-12.zstd\n45539328 /tmp/zstd-13.zstd\n45371392 /tmp/zstd-14.zstd\n45309952 /tmp/zstd-15.zstd\n44093440 /tmp/zstd-16.zstd\n42987520 /tmp/zstd-17.zstd\n41705472 /tmp/zstd-18.zstd\n41447424 /tmp/zstd-19.zstd\n$ ls -1S /tmp/zstd-* | xargs -I{} -n1 sh -c \"echo -n \\\"{} \\\"; \\time -f%e zstdcat -T0 {} &gt; /dev/null\"\n/tmp/zstd-1.zstd 0.37\n/tmp/zstd-2.zstd 0.36\n/tmp/zstd-3.zstd 0.40\n/tmp/zstd-4.zstd 0.47\n/tmp/zstd-5.zstd 0.44\n/tmp/zstd-6.zstd 0.42\n/tmp/zstd-7.zstd 0.40\n/tmp/zstd-8.zstd 0.37\n/tmp/zstd-9.zstd 0.35\n/tmp/zstd-10.zstd 0.40\n/tmp/zstd-11.zstd 0.41\n/tmp/zstd-12.zstd 0.38\n/tmp/zstd-13.zstd 0.39\n/tmp/zstd-14.zstd 0.39\n/tmp/zstd-15.zstd 0.43\n/tmp/zstd-16.zstd 0.37\n/tmp/zstd-17.zstd 0.42\n/tmp/zstd-18.zstd 0.53\n/tmp/zstd-19.zstd 0.68\n\n\n\n\u5727\u7e2e\u30ec\u30d9\u30eb\u3054\u3068\u306e\u5bb9\u91cf\u3068\u5c55\u958b\u6642\u9593\u306f\u3053\u3093\u306a\u611f\u3058\u306b\u306a\u308a\u307e\u3057\u305f\uff0e\u8272\u3005\u52d5\u3044\u3066\u3044\u308b\u74b0\u5883\u306a\u306e\u3067\u304a\u304b\u3057\u305d\u3046\u306a\u3068\u3053\u308d\u304c\u3042\u308a\u307e\u3059\u304c\u5927\u4f53\u306e\u76ee\u5b89\u3068\u3057\u3066\uff0e\n\n\n\n\nKernel build\u6642\u306e\u52d5\u4f5c\n\n\nKernel 5.11.9 \u304c\u6765\u3066\u3044\u305f\u306e\u3067\u30d3\u30eb\u30c9\u3057\u3066\u307f\u307e\u3057\u305f\uff0e\n\n\n\n$ wget https://cdn.kernel.org/pub/linux/kernel/v5.x/incr/patch-5.11.8-9.xz\n$ cd linux-5.11\n$ xzcat ../patch-5.11.8-9.xz | patch -p1\n$ grep ^COMPRESS= /etc/initramfs-tools/initramfs.conf\nCOMPRESS=zstd\n$ time make -j`nproc` bindeb-pkg\n$ ls -1sS ../*5.11.9*\n737300 ../linux-image-5.11.9+-dbg_5.11.9+-5_amd64.deb\n 59584 ../linux-image-5.11.9+_5.11.9+-5_amd64.deb\n  8040 ../linux-headers-5.11.9+_5.11.9+-5_amd64.deb\n  1124 ../linux-libc-dev_5.11.9+-5_amd64.deb\n     8 ../linux-5.11.9+_5.11.9+-5_amd64.buildinfo\n     4 ../linux-5.11.9+_5.11.9+-5_amd64.changes\n$ sudo apt install ../linux-image-5.11.9+_5.11.9+-5_amd64.deb ../linux-headers-5.11.9+_5.11.9+-5_amd64.deb ../linux\n-libc-dev_5.11.9+-5_amd64.deb\n$ file /boot/initrd.img-5.11.9+\n/boot/initrd.img-5.11.9+: Zstandard compressed data (v0.8+), Dictionary ID: None\n$ ls --block-size=1 -s /boot/initrd.img-5.11.9+\n41602048 /boot/initrd.img-5.11.9+\n$ sudo shutdown -r now 'kernel upgrade'\n\n\n\n\u554f\u984c\u306a\u304f zstd \u306b\u306a\u308a\u307e\u3057\u305f\uff0e\n\n\n\n\n\u53c2\u8003URL\n\n\nDebian\u306einitramfs\u306e\u5727\u7e2e\u5f62\u5f0f\u3092zstd\u306b\u3057\u3088\u3046\u3068\u3044\u3046\u30d0\u30b0\u30ec\u30dd\u30fc\u30c8\uff0ebullseye\u306f\u30d5\u30ea\u30fc\u30ba\u3055\u308c\u3066\u3044\u308b\u306e\u3067\u5165\u3089\u306a\u3044\uff0e\n\n\n\n#976054 &#8211; initramfs-tools: [RFC] Compress initramfs file with zstd &#8211; Debian Bug report logs\n\n\n\n\n\n\u74b0\u5883\n\n\n\n$ dpkg-query -W initramfs-tools-core zstd\ninitramfs-tools-core    0.140\nzstd    1.4.8+dfsg-2.1\n$ lsb_release -dr\nDescription:    Debian GNU/Linux bullseye/sid\nRelease:        unstable\n$ uname -srm\nLinux 5.11.9+ x86_64",
            "date_published": "2021-03-25T21:19:39+09:00",
            "date_modified": "2021-03-25T21:41:18+09:00",
            "authors": [
                {
                    "name": "matoken",
                    "url": "https://matoken.org/blog/author/matoken/",
                    "avatar": "https://secure.gravatar.com/avatar/38f5f3b575c5eb45cda6aa659bca119ac7a5e16b46565e869d0030e3bd66981d?s=512&d=mm&r=g"
                }
            ],
            "author": {
                "name": "matoken",
                "url": "https://matoken.org/blog/author/matoken/",
                "avatar": "https://secure.gravatar.com/avatar/38f5f3b575c5eb45cda6aa659bca119ac7a5e16b46565e869d0030e3bd66981d?s=512&d=mm&r=g"
            },
            "tags": [
                "initramfs",
                "kernel",
                "Linux",
                "ZSTD",
                "Debian",
                "sid"
            ]
        }
    ]
}