<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <style type="text/css" style="display:none"></style> </head> <body dir="ltr" style="font-size:12pt;color:#000000;background-color:#FFFFFF;font-family:Calibri,Arial,Helvetica,sans-serif;"> <p><br> </p> <div class="moz-cite-prefix">On 18/02/16 18:17, Ján Tomko wrote:<br> </div> <blockquote type="cite"> <pre>On Thu, Feb 18, 2016 at 05:04:16PM +0300, Maxim Nestratov wrote: </pre> <blockquote type="cite"> <pre>18.02.2016 16:46, Ján Tomko пишет: </pre> <blockquote type="cite"> <pre>On Wed, Feb 17, 2016 at 02:40:05PM +0300, Olga Krishtal wrote: </pre> <blockquote type="cite"> <pre>To update information about ploop volumes inside the a single pool we need to be sure that it is the ploop directory and not some other directory. Ploop volume directory obligatory contains root.hds - image file and disk descriptor - DiskDescriptor.xml. If path to a volume is a path to some directory, we check the existance of this files. </pre> </blockquote> <pre>With each ploop volume being a directory with a ploop disk image and the XML, I think they deserve a separate pool type. </pre> </blockquote> </blockquote> <pre>On second thought, the pool is still just a directory, it's the volumes that are different, so it does belong in the directory-based pools.</pre> </blockquote> <span style="color:rgb(37,37,37); font-family:sans-serif; font-size:14px; font-style:normal; font-variant:normal; font-weight:normal; letter-spacing:normal; line-height:22.4px; orphans:auto; text-align:start; text-indent:0px; text-transform:none; white-space:normal; widows:1; word-spacing:0px; display:inline!important; float:none; background-color:rgb(255,255,255)">The main idea of ploop is to have an image file, use it as a block device,<br> and create and use a file system on that device. It is looks like loop device.<br> However, we do need </span>DiskDescriptor.xml store at the same directory<br> that root.hds (file, that contains ploop).<br> <br> <blockquote type="cite"> <pre> That leaves the mixing of the ploop volumes with the ploop disk images, don't we need a new STORAGE_VOL type?</pre> </blockquote> At the beginning I also had thoughts about it, but:<br> 1) New STORAGE_VOL type will be exclusively for us. No one else will use it.<br> So, we have volume time only for one format.<br> 2) We can avoid such situation, because our ploop format looks a bit like qcow format.<br> (Of course they have have different internal structure, but still, the only difference in such case -<br> DiskDescriptor.xml, that can not be stored in the same file)<br> 3)And we are able to work with STORAGE_VOL_FILE, b<br> <br> <blockquote type="cite"> <pre> </pre> <blockquote type="cite"> <blockquote type="cite"> <pre>The ploop image (root.hds) could be detected as such by the fs pool, but creating and deleting the directories feels out of place in this backend. </pre> </blockquote> <pre>Actually one of the main intention of implementing ploop disk support in storage pool was ability to make it possible to work with existing storage pools like NFS, DIR, FS. </pre> </blockquote> <pre>The 'image in a directory' still won't work with older libvirtd. </pre> <blockquote type="cite"> <pre>Creating a separate storage pool makes it impossible. Also, our future plans to expand storage pools with new pool type like VZ storage and CEPH FS becomes worthless either. </pre> </blockquote> <pre>Jan </pre> </blockquote> <br> </body> </html>