Why large initial vmdf/vldf-files?

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Why large initial vmdf/vldf-files?

Postby fgsimon » Mon May 21, 2012 1:04 pm

Hi all,
We are getting vmdf 400GB and vldf 20GB, when makeing a Virtual Restore Database from a Hyperbac-backed Database of an 8GB compressed database backup file..

I can't help feeling that our v-files are way too large, right after restoring.. what are your thoughts?
How large are your v-files, generally?

Thank's,
Simon
fgsimon
 
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Postby RajK » Wed May 23, 2012 2:35 pm

I am investigating this as part of the support case raised with us.

SVR should normally have a footprint of less than 10 percent of the database backup size.

I will post an update here when the investigation is complete. Thanks for your patience and feedback in this matter.
RajK
 
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Re:

Postby fgsimon » Thu May 24, 2012 9:55 am

RajK wrote:I am investigating this as part of the support case raised with us.

SVR should normally have a footprint of less than 10 percent of the database backup size.

I will post an update here when the investigation is complete. Thanks for your patience and feedback in this matter.


Thank's! Apoplogies for my typo, I meant MB, not GB: vmdf 400MB and vldf 20MB. Perhaps that is what can be expected?
fgsimon
 
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Postby RajK » Wed May 30, 2012 12:55 pm

As mentioned in the support email thread I am just posted the response in this forum post.

In regards to the sizes you have reported:

”Another question: when making a virtual restore from a hyperbac in zip-format, the vmdf file is 435MB, is that not very big for an initial size? (The vldf is 37MB. The zip is 8GB and the original mdf/ldf are 36.5Gb/3.4Gb.)”

The ratio of comparison is actually quite good. This roughly translates to less than 10% disk space footprint.

I am not sure if we can optimise any further than that.

Thanks for your patience and feedback in this matter.
RajK
 
Posts: 58
Joined: Thu Feb 02, 2012 8:21 am

Re:

Postby fgsimon » Wed May 30, 2012 12:56 pm

OK, I was not sure what size files to expect. thank you for your response.
/Simon
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