Re: [PATCH 3/3] vm-img: Handle sparse files efficiently

[Jan Kiszka <jan.kiszka@siemens.com>]

On 07.03.22 15:09, Henning Schild wrote:
> Am Mon, 7 Mar 2022 10:46:34 +0100
> schrieb Jan Kiszka <jan.kiszka@siemens.com>:
> 
>> On 07.03.22 10:04, Henning Schild wrote:
>>> Am Sat, 5 Mar 2022 17:34:50 +0100
>>> schrieb Jan Kiszka <jan.kiszka@siemens.com>:
>>>   
>>>> From: Jan Kiszka <jan.kiszka@siemens.com>
>>>>
>>>> Saves space in case the image contains any sparse files.
>>>>
>>>> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>>>> ---
>>>>  meta/classes/vm-img.bbclass | 6 +++---
>>>>  1 file changed, 3 insertions(+), 3 deletions(-)
>>>>
>>>> diff --git a/meta/classes/vm-img.bbclass
>>>> b/meta/classes/vm-img.bbclass index 4bc977b9..27aedf12 100644
>>>> --- a/meta/classes/vm-img.bbclass
>>>> +++ b/meta/classes/vm-img.bbclass
>>>> @@ -93,15 +93,15 @@ do_create_ova() {
>>>>          export VM_UUID=$(uuidgen)
>>>>          # create ovf
>>>>          cat ${PP_WORK}/${OVF_TEMPLATE_STAGE2} | envsubst >
>>>> ${PP_DEPLOY}/${OVA_NAME}.ovf
>>>> -        tar -cvf ${PP_DEPLOY}/${OVA_NAME}.ova -C ${PP_DEPLOY}
>>>> ${OVA_NAME}.ovf
>>>> +        tar -cvSf ${PP_DEPLOY}/${OVA_NAME}.ova -C ${PP_DEPLOY}
>>>> ${OVA_NAME}.ovf 
>>>>          # VirtualBox needs here a manifest file. VMware does
>>>> accept that format. if [ "${VMDK_SUBFORMAT}" = "monolithicSparse"
>>>> ]; then  
>>>
>>> Not sure that already suggested it but we did not do it.
>>>   
>>>>              echo
>>>> "SHA${OVA_SHA_ALG}(${VIRTUAL_MACHINE_IMAGE_FILE})=$(sha${OVA_SHA_ALG}sum
>>>> ${PP_DEPLOY}/${VIRTUAL_MACHINE_IMAGE_FILE} | cut -d' ' -f1)" >>
>>>> ${PP_DEPLOY}/${OVA_NAME}.mf echo
>>>> "SHA${OVA_SHA_ALG}(${OVA_NAME}.ovf)=$(sha${OVA_SHA_ALG}sum
>>>> ${PP_DEPLOY}/${OVA_NAME}.ovf | cut -d' ' -f1)" >>
>>>> ${PP_DEPLOY}/${OVA_NAME}.mf
>>>> -            tar -uvf ${PP_DEPLOY}/${OVA_NAME}.ova -C ${PP_DEPLOY}
>>>> ${OVA_NAME}.mf
>>>> +            tar -uvSf ${PP_DEPLOY}/${OVA_NAME}.ova -C ${PP_DEPLOY}
>>>> ${OVA_NAME}.mf fi
>>>> -        tar -uvf ${PP_DEPLOY}/${OVA_NAME}.ova -C ${PP_DEPLOY}
>>>> ${VIRTUAL_MACHINE_IMAGE_FILE}
>>>> +        tar -uvSf ${PP_DEPLOY}/${OVA_NAME}.ova -C ${PP_DEPLOY}
>>>> ${VIRTUAL_MACHINE_IMAGE_FILE} EOSUDO  
>>>
>>> Did you get around to testing this on vmware and vbox? Do you think
>>> it would need to be tested? I could to that.
>>>   
>>
>> That would be valuable. Just add a sparse file to the image (dd
>> if=/dev/zero of=sparse.file bs=1G seek=1 count=0) and check if that
>> bloats the files. And, of course, check if things still boot.
> 
> NACK, breaks ova import into both vmware and virtualbox. I compared and
> it is really this patch which breaks both.
> 
> Did not check the vmware logs but vbox says
> VERR_TAR_UNSUPPORTED_GNU_HDR_TYPE

Amazingly primitive format, this OVO...

> 
> So this tarball does not support it because its consumers both do not.
> 

OK, thanks for testing. We may then consider whether to take patch 2 as
well as it may surprise constrained consumers. Patch 1 is fine as it
only targets Isar itself.

Jan

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