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Re: [Swift] Where's Object's metadata located ?

 

> Q1: Where's the metadata of an object ?
It's stored in extended attributes on the filesystem itself. This is
reason XFS (or other filesystem supporting extended attributes) is
required.

> Could I find the value?
Sure. You just need some way of a) identifying the object on disk and,
b) a means of querying the extended metadata (using for example the
python xattrs package).

> Q2: What if a large object be interrupted during upload , will the manifest objects be deleted?
Large objects (i.e. those > 5Gb) must be split up client-side and the
segments uploaded individually. When all the segments are uploaded the
manifest must then be created by the client. What I'm trying to get at
is that each segment and even the manifest are completely independent
objects. A failure during the upload of any one segment has no impact
on other segments or the manifest.

Adrian


On 16 June 2012 09:53, Kuo Hugo <tonytkdk@xxxxxxxxx> wrote:
> Hi folks ,
>
> Q1:
> Where's the metadata of an object ?
> For example the "X-Object-Manifest". Does it store in inode ?
> I did not see the matadata "X-Object=Manifest" in container's DB.
>
>  Could I find the value?
>
> Q2:
> What if a large object be interrupted during upload , will the manifest
> objects be deleted?
> For example ,
> OBJ1 :200MB
> I execute $>swift upload con1 OBJ1 -S 1024000
> I do a force interrupt while send segment 10.
>
> I believe that OBJ1 won't live in con1 , what will happen to the rest
> manifest objects?
>
> Those objects seems still live in con1_segments container. Is there any
> mechanism to audit OBJ1 and delete those manifest objects ?
>
>
>
> --
> +Hugo Kuo+
> tonytkdk@xxxxxxxxx
> +886 935004793
>
>
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