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Glazing over at this, but kind of follow that aligning the partition placement, and most particularly, the placemt of actual data, can improve perfomance of flash media - that's cards, pendrives and SSD. The shift of alignment may also be responsible for cases when readyboost performance is noted as unacceptable with a flashdrive formatted in FAT/FAT32 but improves when reformatted in NTFS.

As I understand it, most flash media uses 4k pages (giving it similar alignment issues to 4k sector hard drives) and also 64,128 or 256k erase blocks.

The burning question, is there a better way to do it under Windows? - Even just a way of repartitioning, since for pendrives and cards, moving the data off an back on is not too big a job.

The read performance may increase slighly, particularly for 4k reads, but the write performance can be massively improved.

I dont know other options
Welcome matth

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tracked down a little more info, and it would seem the windows version of Guests cannot see links. Registration or Login is required.
can be used to push the FAT/FAT32 sectors into alignment by adjusting the reserved sector count - or maybe the line of least resistance would be to go for partition align and use NTFS (where EVERYTHING is in units of 4k)

I'm lost on this

The first time aligning received attention, was for the "advanced format" or 4k sector hard drives, where the default partition position of XP resulted in NTFS 4k clusters being a 512 byte logical sector out of step - the major negative effect of that misalignment being that 4k writes end up converted to two 4k read/modify/writes.

Now on NAND flash media (and most common flash storage is NAND based), reading and writing are usually based on 4k pages, and at a higher level of optimization, erasing is in larger blocks.

A further complexity, is that when FAT or FAT32 filesystem is used, while the cluster are 4k or multiples of, the partition begins with the allocation table which is NOT cluster aligned, so even if the partition is aligned, the actual data is not.

Why care? On some write patterns, it can be as big as the difference between a "fast" flash drive and a "slow" one - particularly where a drive shows miserable results on a 4k write test, this suggests that the alignment is not optimum

(08-06-2011 10:59 AM)grr Wrote: Guests cannot see links. Registration or Login is required.
I'm lost on this