Does anyone still need to create legacy HFS filesystems?

[Chris Murphy]

On Feb 2, 2012, at 6:45 PM, John Reiser wrote:

>> Does anyone object [to dropping support for HFS]?
> 
> Plain HFS has no journal, so there are workloads where HFS is faster
> than HFS+ which has a journal.

Mac OS Extended or HFS+ or HFS Plus, does not inherently have a journal. There is a separate variant called Journaled HFS+ (acronym appears as HFSJ or jhfs+). There is yet another variant called HFSX which is case-sensitive, but also has more feature potential than HFSJ.

For nearly nine years Apple's tools have only created HFSJ/jhfs+ by default.

>  Is it economical to cater to such cases?
> Probably not.  However, I do have a PowerPC Mac Mini that runs plain HFS
> and Fedora 10 with ext3.

Are you sure you mean HFS? The original maximum volume size for Mac OS Standard (HFS) format, was 2GB. The maximum number of allocation blocks is 65,536. For a 100GB disk, your allocation block would need to be 1.6MB. Considering Mac OS X 10.7, today's current Apple operating system, is optimized for 4K allocation block sizes, the performance and efficiency of a 1.6MB allocation block would be hideous.

HFS is dead. I'm not even finding a partition type GUID for it, it was always intended to be used with the APM partitioning scheme (not MDB or GPT).

Chris Murphy