> From: Richard Elling [mailto:richard.ell...@gmail.com] > > > ----------- To calculate size of DDT ----------- > zdb -S poolname Look at total blocks allocated. It is rounded, and uses a suffix like "K, M, G" but it's in decimal (powers of 10) notation, so you have to remember that... So I prefer the zdb -D method below, but this works too. Total blocks allocated * mem requirement per DDT entry, and you have the mem requirement to hold whole DDT in ram.
> zdb -DD poolname This just gives you the -S output, and the -D output all in one go. So I recommend using -DD, and base your calculations on #duplicate and #unique, as mentioned below. Consider the histogram to be informational. > zdb -D poolname It gives you a number of duplicate, and a number of unique blocks. Add them to get the total number of blocks. Multiply by the mem requirement per DDT entry, and you have the mem requirement to hold the whole DDT in ram. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
