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

[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.

Thanks,
Jan

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