Everywhere I read that internally SSDs are structured in 4K or larger "pages", which grouped in "blocks" of about 128-256 pages (1, 2). SSDs work with these pages and blocks, "they can only erase data at the block level" (thus the block of pages is called "[NAND] erase block"). And the 512B blocks for the partition are emulated (which is done for legacy reasons).
I'm trying to get educated on SSDs, since I have some weird lags/freezes during writes to my Sandisk U100 on Samsung 9 np900x3c laptop. And one useful thing would be to correctly find out what pages/blocks my SSD has?
Is there a utility or
/sys/... file on Linux to determine the SSD page size?
Or "the drive and Googling the part numbers on the NAND chips may be needed", as in the comment?
fdisk shows me sector size (both physical and logical) and I/O 512 byte:
Disk /dev/sda: 128.0 GB, 128035676160 bytes 255 heads, 63 sectors/track, 15566 cylinders, total 250069680 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x4b914713 Device Boot Start End Blocks Id System /dev/sda1 * 2048 50331647 25164800 83 Linux /dev/sda2 50331648 239583231 94625792 83 Linux /dev/sda4 239583232 250068991 5242880 82 Linux swap / Solaris
What is "physical" sector size here? It doesn't seem to be the parameter of the SSD drive itself, since everybody say SSD pages are 4K+. Is it the emulated parameter for the disk? And "logical" is the sector size for the partition? Also, what is I/O size?
This question is probably the same as this one for USB flash -- the answer is missing the point there,
man fsstat says
fsstat displays the details associated with a file system and the question is about the disk itself. My post has more details, maybe it would attract better responses?