cost of tdb transactions on ext4 with barriers

[tridge at samba.org]

Hi Scott,

 > I'm assuming you've got a 5400 RPM drive on your laptop.  Any chance 
 > these would be much better using a SSD?

It's a 7200 (a seagate momentus 500G 7200.4), but that doesn't matter
much for this test. I was using a 2G test partition, so it wasn't the
disk size.

On a SSD it will be better of course, as barriers are much cheaper,
but it probably will wear out the SSD much faster then it needs to.

Cheers, Tridge