ext4 testing in the F10 release cycle

[Chris Snook]

Eric Sandeen wrote:
> Peter Robinson wrote:
> 
>> Do you have recommended FS creation parameters for SSDs?
> 
> Not really; there has unfortunately been very little (or no)
> optimization of ext4 for SSDs at this point ...
> 
> It'd probably be an allocator heuristic change but nobody's looked into
> that yet.
> 
> Once we get ext4 raid-geometry-aware, we can probably use some of that
> geometry info to better match up with the erase block sizes on an SSD at
> least...

In my testing (without a filesystem), raid-optimized access works quite well on 
SSDs, so that should carry over quite effortlessly.  The places where we need 
work are:

a)	Make jbd do fewer small writes.

b)	Write a partitioning tool that doesn't suck the way fdisk and parted do, so 
we can partition properly for the geometry of modern storage.

c)	Put an alignment option in the installer, so people can optimize their 
partitions and filesystems for SSDs, RAID, and anything else where alignment 
matters.

-- Chris