From nobody Mon Nov 15 16:35:56 2021 X-Original-To: freebsd-hackers@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 5D75C18881D0 for ; Mon, 15 Nov 2021 16:36:05 +0000 (UTC) (envelope-from mad@madpilot.net) Received: from mail.madpilot.net (vogon.madpilot.net [159.69.1.99]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4HtFF11cpqz4VBX for ; Mon, 15 Nov 2021 16:36:02 +0000 (UTC) (envelope-from mad@madpilot.net) Received: from mail (mail [192.168.254.3]) by mail.madpilot.net (Postfix) with ESMTP id 4HtFDw62wrz6fWD; Mon, 15 Nov 2021 17:36:00 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=madpilot.net; h= content-transfer-encoding:content-type:content-type:in-reply-to :from:from:references:content-language:subject:subject:date:date :message-id:received; s=bjowvop61wgh; t=1636994158; x= 1638808559; bh=0OjJull/9vnM5l8/KnnEDBV62v+LYkpujoY0dZCJb6Q=; b=d 3IsSx4sxNub0qevTk9l/JNWLyh145qkXX2L4/0JSyoXewSGTky52UZS3HvyRY5Op m8fk7nTT37R2tud9B1l2aa25FYomYua2lx+bYMz5c7ud3FJ2FnIalgh2Rx7y9YUd unhjbhoOH0RoScc60rSANvhN6tHrNxvj4gq85mDbG5RXyKgeAm672OPBKIiv7Rbb gtiBweOE37Pd9w1Z5nML0AhCW70YH0m7GzhYipdPnpQ7ydFECE8VUp2iYyWTfEHb B1TqHqShPkMvgvEc8ru/TbkY0grjPb6ZsBQN22Q7sdhUJzgIV6dkfylMJua53gzB AhumyhYj5nfnfy/2tk0NQ== Received: from mail.madpilot.net ([192.168.254.3]) by mail (mail.madpilot.net [192.168.254.3]) (amavisd-new, port 10026) with ESMTP id N_8SRXhRt2gv; Mon, 15 Nov 2021 17:35:58 +0100 (CET) Message-ID: Date: Mon, 15 Nov 2021 17:35:56 +0100 Subject: Re: What happen with disk space? Content-Language: en-US To: Rozhuk Ivan , freebsd-hackers@FreeBSD.org References: <20211115185455.1cb9992a@rimwks.local> In-Reply-To: <20211115185455.1cb9992a@rimwks.local> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4HtFF11cpqz4VBX X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-4.00 / 15.00]; TAGGED_RCPT(0.00)[]; REPLY(-4.00)[] Reply-To: mad@madpilot.net From: Guido Falsi via freebsd-hackers X-Original-From: Guido Falsi X-Spam: Yes X-ThisMailContainsUnwantedMimeParts: N List-Id: Technical discussions relating to FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-hackers List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-hackers@freebsd.org On 15/11/21 16:54, Rozhuk Ivan wrote: > > > # df -cHi > Filesystem Size Used Avail Capacity iused ifree %iused Mounted on > .... > /dev/concat/16TB________.eli 16T 16T 9.0G 100% 22k 246M 0% /mnt/16TB________ > /dev/mirror/10T________.eli 9.7T 8.8T 124G 99% 45k 1.2G 0% /mnt/10T________ > /dev/gptid/87978976-10a9-11eb-ad6e-346346346346.eli 5.8T 4.1T 1.3T 76% 1.3M 732M 0% /mnt/backup > /dev/ada3p1.eli 5.8T 4.1T 1.3T 76% 1.3M 732M 0% /mnt/tmp > > Why Size != Used + Avail? AFAIK in UNIX it has always been like this, I guess since 4BSD at least, maybe even in v6. explanation is in minfree, -m option tu tunefs(8). part of the disk space is reserved for system usage and is accessible only to root. df(1) calculates avail based on that, while size is the actual full size (if I remember correctly). ZFS too shows the same behaviour. -- Guido Falsi