getting to 4K disk blocks in ZFS

[Steven Hartland]

----- Original Message ----- 
From: "Don Lewis" <truckman at FreeBSD.org>


> On 13 Oct, Charles Swiger wrote:
>> Hi--
>> 
>> On Oct 13, 2014, at 2:25 PM, Lyndon Nerenberg <lyndon at orthanc.ca>
>> wrote:
>> [ ... ]
>>> On any real-world system where you're running ZFS, it's unlikely the
>>> 4K block overhead is really going to be an issue.  And the underlying
>>> disk hardware is moving to 4K physical sectors, anyway.  Sooner or
>>> later you're just going to have to suck it up.
>> 
>> Or SSDs, which currently have anywhere from 2KB to 16KB "sectors".
> 
> Which is even worse because you're more likely to care about wasted
> space because of the much higher cost per byte.
> 
>> I suspect that MIX -- http://en.wikipedia.org/wiki/MIX_%28Email%29 --
>> will gain in popularity.  Big messages are kept one per file, just as
>> Maildir does, but MIX also does a pretty good job of conserving inodes
>> (or equivalent) and minimizing wasted space from intrinsic
>> fragmentation due to filesystem blocksize by aggregating small
>> messages together.
> 
> Interesting, but it would be nice to have a more generic solution that
> could be used to solve the equivalent problem with /usr/ports and
> similar sorts of things.  For instance, it looks like /usr/src expands
> by quite a bit on an ashift=12 raidz1, though not quite as much as my
> mail spool.

Dont worry about ports just create a volume set it to lz4 and
forget about it.

    Regards
    Steve