Non-aligned SSD Compensation

[WhoBeDaPlaya]

I realize that having non-aligned partitions is BadJuju for SSDs. But, from a reliability standpoint, would it be possible to somewhat compensate for that by increasing reserve capacity (eg. only actively using 80GB on a 90GB SSD, keeping the remainder unpartitioned/unallocated)?

 

[Elixer]

What, make a 10GB partition at the beginning? That would be a good way to waste some space.
If you mean at the end, then no, that won't help. The starting offset must be a multiple of 1024, or else all read/write access to the SSD is skewed, and performance suffers.

 

[WhoBeDaPlaya]

I understand that performance will tank due to unaligned reads/writes. What I'm talking about is SSD life / reliability and unallocating a chunk of space to act as additional reserve capacity.

 

[Elixer]

In theory, that will work, but are you actually going to write that much data on the SSD to make a difference ?

 

[StarTech]

I realize that having non-aligned partitions is BadJuju for SSDs. But, from a reliability standpoint, would it be possible to somewhat compensate for that by increasing reserve capacity (eg. only actively using 80GB on a 90GB SSD, keeping the remainder unpartitioned/unallocated)?

What are you trying to get to or to avoid? Why not just align the partition ?

 

[WhoBeDaPlaya]

Cloning a disk in a work machine and running it off of a small Agility 3 90GB SSD instead of the clunky old Seagate 80GB. Would like to not modify the partition if possible.

 

[=Wendy=]

You can align the partition after cloning, on the fly.
http://www.paragon-software.com/home/partition-alignment/

 

[Smoblikat]

Yes that would work, if you left 10gb unpartitioned, but as was said earlier performance will suffer. In theory it would compensate enough to allow a longer life. Though, how many writes are you planning on doing?

 

[WhoBeDaPlaya]

It should be hit that heavily, as its just an OS + scratch drive for CentOS 5.5.
Would prefer to not modify the partitions at all, hence the happy consequence of extra reserve capacity

However, this line of inquiry should also be relevant for my folks' systems. I was considering switching them (about 6 XP rigs) over to SSDs and TrueImage seems to constantly default to a non-aligned offset when restoring XP. Yes, I would prefer that they switched to Win7, but that is out of my hands.

 

[mv2devnull]

Tools like Clonezilla do offer two modes: clone whole disk and clone individual partitions. The latter clearly allows change of alignment during copy because you pre-create partitions as you like them. MBR naturally has to be copied/recreated too.

The good thing is that you can clone, test the SSD, and then either revert to HDD (and try different cloning method) or be happy with the aligned SSD.

 

[RU482]

having unaligned partitions on an SSD results, effectively, in two writes occuring when only one would be necessary on an aligned SSD. No buffer or partition is going to resolve that

 

[WhoBeDaPlaya]

having unaligned partitions on an SSD results, effectively, in two writes occuring when only one would be necessary on an aligned SSD. No buffer or partition is going to resolve that

Understood. What I was attempting to do was to reduce the impact on the SSD's lifespan by increasing the reserve capacity.

Did see that option in Clonezilla (which is what I used to mirror the HDD to the SSD), but haven't played around with it yet. Will have to do that during a weekend on the qt :sneaky: