4k partition alignment for SSDs

[LoadWB]

There are plenty of utilities out there to align x86 partitions along the 4k page boundaries in SSDs.

Does anything exist for the Amiga to assist in doing so?  Should we even consider this important?

[chris]

There are plenty of utilities out there to align x86 partitions along the 4k page boundaries in SSDs.

Does anything exist for the Amiga to assist in doing so?  Should we even consider this important?

This thread contains some info (OS4 thread, but not particularly OS4 specific): http://forum.hyperion-entertainment.biz/viewtopic.php?f=14&t=3573
It references this post which is probably about as good as you'll get it. I'm not sure this will actually align the blocks correctly though: http://www.amigans.net/modules/xforum/viewtopic.php?post_id=101939#forumpost101939

I have an SSD sitting on my desk but I think I'll wait for OS4 to support it properly before putting it in!

[LoadWB]

Thanks.  Helpful information in those.  I will likely have to redo this drive to match the settings for page boundaries, which I expected.

One question, though: numerous people point out that only FFS can handle block sizes over 512 bytes, yet documentation for SFS and PFS3 both indicate the ability to handle the 4k block sizes.

Right now on my 120GB SSD HDToolBox set up all partitions with block sizes of 1k and all seems to be working fine (with the exception of a bad SFS block which I am pretty certain I caused with power.)

[chris]

Thanks.  Helpful information in those.  I will likely have to redo this drive to match the settings for page boundaries, which I expected.

One question, though: numerous people point out that only FFS can handle block sizes over 512 bytes, yet documentation for SFS and PFS3 both indicate the ability to handle the 4k block sizes.

I was a bit puzzled about that myself, however it might be SFS2 only supports 512 byte blocks.  I'm pretty sure the old SFS supports others as I remember seeing a table showing what the maximum volume size was with different block sizes under SFS.

PFS isn't an included OS4 filesystem (and doesn't even have an OS4 native version AFAIK) so I doubt that is included in the statement, given that the discussion was OS4 focussed.

[psxphill]

There are plenty of utilities out there to align x86 partitions along the 4k page boundaries in SSDs.

Does anything exist for the Amiga to assist in doing so?  Should we even consider this important?

Alignment for flash is quite important. However some drives do their best to mitigate the problem, so it's not always entirely obvious.

The alignment for 4k on x86 isn't anything to do with SSDs though, it's because magnetic drives went from 512 byte sectors to 4k sectors. SSDs have even larger sector sizes and often cannot erase a single sector. If the write page size is 32k and the erase size is 1mb then even using a 4k block is still not great.

There isn't much in the way of information on sector sizes and erase size & you may not even be able to tell if you try various options and benchmark them as the drives have been designed to hide it. The wrong settings might affect the lifetime of the SSD, but it's likely that the drive will get written to a lot less than it would in a PC so it might be ok.