Impossible compression ratio on ZFS

Steven Hartland killing at
Mon Jun 13 09:25:06 UTC 2011

I've just done an optimisation of a mysql table which is located
on a compressed zfs partition and spotted that the size reported
by du is impossibly small for the file:-

du -h detail*
1.5K    detail.frm
7.5K    detail.ibd

ls -l detail*
-rw-rw----  1 mysql  mysql       8660 Jun 13 10:00 detail.frm
-rw-rw----  1 mysql  mysql  650117120 Jun 13 10:04 detail.ibd

The table format for those interested is 3 int's, 3 indexes and
contains 8million rows.

I highly doubt that my 620MB table is taking up just 7.5K on disk
any ideas?


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