12 Apr
2015
12 Apr
'15
12:51 a.m.
On Fri, Apr 10, 2015 at 11:03 AM, ANDY HOLT <andy.holt at tesco.net> wrote:
d) AFAICT ZFS doesn't use the trick used by some
*ix filesystems of packing the data contents for small files into the directory.
(to do so would clash with the reliability focus of ZFS)
That capability has recently been added to OpenZFS as the
"embedded_data" feature, so it is now available on Illumos, FreeBSD,
Linux, and OSX:
"When this feature is enabled, the contents of highly-compressible
blocks are stored in the block "pointer" itself (a misnomer in this
case, as it contains the compresseed data, rather than a pointer to
its location on disk). Thus the space of the block (one sector,
typically 512 bytes or 4KB) is saved, and no additional i/o is needed
to read and write the data block."