QA talk:Testcase Mediakit ISO Size

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  • robatino - I've been told there's no specific minimum size, so it doesn't really matter.
  • jlaska - I think this test has a larger focus on ensuring that the ISO's are not larger than the media for which they are intended (e.g. CD or DVD). However, a minimum size was also added so that we weren't shipping media with no packages. As is sometimes the case during the compose process, a disc6.iso can be produced which contains no packages. This is rare, but also something the disk size check was validating. Hope this helps!
  • robatino For RC4, the exact size of F13-Beta-i686-Live-KDE.iso is 734003200 bytes. A zero-byte file of this size can be created with the command
dd if=/dev/zero of=dummy-file bs=2048 count=358400

Running the prescribed test on it shows a size of 701M, even though its exact size is 700 MiB = 700*1024^2 bytes. Are the KDE live images still supposed to be CD-sized, and if so, does this image pass the test, or not?

In particular, it appears that an exactly 700 MiB image will fit.

  • robatino The ISO size should be the same as what the ISO header says it should be - the product of the Logical block size and Volume size listed by "isoinfo -d -i file.iso". I noticed that in the Nouveau test day, one of the Live ISOs was bigger than what the header indicated. I've never seen this with install images, though. This would be easy to test since it doesn't require downloading the full ISO, just the beginning of it. Should this be added as an additional test?

700 MiB vs 703.125 MiB

Bruno asked why 703.126 MiB wasn't used instead of 700 MiB for the single CD-ROM image size. Andre noted that, according to http://lists.fedoraproject.org/pipermail/test/2010-April/089943.html, 703 MiB might not be safe.

 My feeling is unless you're really, really sure that it is, it's not worth
 exceeding the advertised size of 700 MiB (with the understanding that's what
 "700 MB" actually means) to gain at most an extra 3 meg.