Re: dd/skip-seek-past-file fail on ecryptfs

[Bert Wesarg]

2009/9/14 Pádraig Brady <address@hidden>:
> Bert Wesarg wrote:
>> This short mail is only to inform you, that the dd/skip-seek-past-file
>> test fail on a ecryptfs mount. Because this commands takes a long time
>> and eat my hard disk space:
>>
>> truncate --size=$OFF_T_MAX in
>>
>> More infos at monday.
>
> So ecryptfs doesn't allow sparse files:
> http://ecryptfs.sourceforge.net/ecryptfs-faq.html#sparse
>
> Even still it seems like ecryptfs should have immediately
> returned, given the "seek" offset is larger than the file
> system size?
>
> The attached patch should work around this issue.
Thanks for the patch. But the require_sparse_support_() does not
trigger on a ecryptfs. du -sk still reports 0. I generated bigger
files (up to 8GB) with this code and it still doesn't have triggered.
If I don't remove the sparse files from previous runs than, at some
point (which may have todo with the RAM size, 4GB here), these files
will get written to disk with a du -sk size greater than zero. Even
after a sync(1) the current file is still 0.

Thanks,
Bert
>
> cheers,
> Pádraig.
>