FreeBSD, SSD's and partition alignment

[Andrew Snow]

> I'd like to discuss this subject a bit if anyone's interested.
> - partition alignment seems to be a real problem with some of today's flash
> and RAID media. I think people need to know one could easily increase
> performance (and media wear!) as no one knows this problem exists.

Thanks for your interesting post!

In my humble opinion, FreeBSD should not worry about this problem for 
the following reasons:

1. Performance for random write I/O still sucks even when the sector 
boundary is correct.  Doing something like untarring src or ports causes 
many small write I/Os, and it is simply a shortcoming of early 
generation flash controller technology that they erase and rewrite in 
large blocks.

2. This problem will go away when flash controller technology improves. 
  Intel SSDs have already demonstrated they can have great performance 
*and* a small erase block size, mitigating the issue completely.  This 
technology will trickle down to the cheaper flash SSDs over time.


- Andrew