>  > The files are approx. 1 MB with an thumbnail of approx. 4 KB.
>  >
>
> So the 1 MB files are stored as ~8 x 128K recordsize.
>
> Because of
>         5003563 use smaller "tail block" for last block of object

I tried to search for this but only saw references to this and similar
threads. Is there a database where I can search?

> The last block of you file is partially used. It will depend
> on your filesize distribution by without that info we can
> only guess that we're wasting an avg of 64K per file. Or 6%.
>
> If your distribution is such that most files are slightly
> more than 1M, then we'd have 12% overhead from this effect.
>
> So using 16K/32K recordsize would quite possibly help as
> files would be stored using ~ 64 x 16K blocks with an
> overhead of < 1-2% (0.5 blocks wasted  every 64).

Variying recordsizes and no compression:

Recordsize=2k: 426G
Recordsize=4k: 417G
Recordsize=8k: 411G
Recordsize=16k: 412G
Recordsize=32k: 417G

Default recordsize of 128k and compression:

Standard-compression:  410G
Gzip-1: 402G
Gzip-6: 402G

Recordsize=16k and standard compression: 406G

Recordsize 8- and 16k comes closest to 401 GB on vxfs.

Should I try with a single hardrive and verify 16k recordsize disk usage?

-- 
regards
Claus

When lenity and cruelty play for a kingdom,
the gentlest gamester is the soonest winner.

Shakespeare
_______________________________________________
zfs-discuss mailing list
[email protected]
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss

Reply via email to