cloudstack-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Mike Tutkowski <>
Subject S3/Swift Problem around Virtual Size
Date Fri, 22 Aug 2014 20:38:24 GMT

This was brought up in a different e-mail thread, but I wanted to make it
more clear that it's related to CloudStack's download code around S3/Swift,
so I'm opening up a new thread.

Francois (from CloudOps) noticed today that when he downloaded a template
(VHD format) to Swift (but it looks like the same applies for S3) that the
physical and virtual sizes are set to be the same.

This appears to have the following consequence:

You can download a template with a physical size of, say, 3 GB and a root
disk that's supposed to be, say, 20 GB. Instead of the virtual size showing
as 20 GB, it shows as 3 GB.

This is not an issue with NFS. In that situation, the two sizes are
correctly accounted for.

What later can happen is the template is downloaded from Swift and takes up
an unexpected amount of space on the XenServer storage repository (SR).

If there is enough space on the SR, this isn't too big of a deal. However,
for so-called managed storage plug-ins (examples are SolidFire and
CloudByte), this will lead to them dynamically creating a SAN volume of the
wrong size.

Francois opened up the following ticket:


*Mike Tutkowski*
*Senior CloudStack Developer, SolidFire Inc.*
o: 303.746.7302
Advancing the way the world uses the cloud

  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message