Date: Wed, 18 Oct 2023 15:42:37 +0200 (CEST) From: Ronald Klop <ronald-lists@klop.ws> To: void <void@f-m.fm> Cc: freebsd-fs@freebsd.org Subject: Re: free space considerations writing bhyve image to a zvol Message-ID: <1733602178.6691.1697636557003@localhost> In-Reply-To: <ZS_WZD-JlHEo_Em5@int21h> References: <ZS_WZD-JlHEo_Em5@int21h>
next in thread | previous in thread | raw e-mail | index | archive | help
------=_Part_6690_1862543576.1697636556997 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit You can test how much it will compress your linuxvm.img. $ [/tmp] ls -l ./bla.txt -rw------- 1 ronald wheel 5242880 Oct 18 15:39 ./bla.txt $ [/tmp] lz4 -c ./bla.txt | wc -c 20604 So do "lz4 -c linuxvm.img | wc -c" and it will print about the size of the zvol you need. NB: What keeps you from just trying to write it to the zvol and see if it works? Regards, Ronald, Van: void <void@f-m.fm> Datum: woensdag, 18 oktober 2023 14:58 Aan: freebsd-fs@freebsd.org Onderwerp: free space considerations writing bhyve image to a zvol > > A linux file-backed vm was created initially like this: > > truncate -s 2T linuxvm.img > > Within the vm, df -h reports 1.1Tb used in total. > Externally, on the freebsd host, the linuxvm.img is 2Tb. > > If i write the vm to a 1.6Tb zvol with compression set (lz4), > would it be feasible to expect the vm to work? > > I expect it might break the vm's filesystem internally, > now, thinking about it. > -- > > > > ------=_Part_6690_1862543576.1697636556997 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit <html><head></head><body>You can test how much it will compress your linuxvm.img.<br> <br> $ [/tmp] ls -l ./bla.txt<br> -rw------- 1 ronald wheel 5242880 Oct 18 15:39 ./bla.txt<br> <br> $ [/tmp] lz4 -c ./bla.txt | wc -c<br> 20604<br> <br> <br> So do "lz4 -c linuxvm.img | wc -c" and it will print about the size of the zvol you need.<br> <br> NB: What keeps you from just trying to write it to the zvol and see if it works?<br> <br> Regards,<br> Ronald,<br> <br> <p><strong>Van:</strong> void <void@f-m.fm><br> <strong>Datum:</strong> woensdag, 18 oktober 2023 14:58<br> <strong>Aan:</strong> freebsd-fs@freebsd.org<br> <strong>Onderwerp:</strong> free space considerations writing bhyve image to a zvol</p> <blockquote style="padding-right: 0px; padding-left: 5px; margin-left: 5px; border-left: #000000 2px solid; margin-right: 0px"> <div class="MessageRFC822Viewer" id="P"> <div class="TextPlainViewer" id="P.P">A linux file-backed vm was created initially like this:<br> <br> truncate -s 2T linuxvm.img<br> <br> Within the vm, df -h reports 1.1Tb used in total.<br> Externally, on the freebsd host, the linuxvm.img is 2Tb.<br> <br> If i write the vm to a 1.6Tb zvol with compression set (lz4),<br> would it be feasible to expect the vm to work?<br> <br> I expect it might break the vm's filesystem internally,<br> now, thinking about it.<br> -- <br> </div> <hr></div> </blockquote> <br> </body></html> ------=_Part_6690_1862543576.1697636556997--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?1733602178.6691.1697636557003>