Sign in with
Sign up | Sign in
Your question

Does SSD Read Write MB/s Depend on NTSF File Size?

Last response: in Windows 7
Share
December 28, 2009 9:26:05 PM

I have noticed that ATTO performance charts of SSD's shows MB/s from 4k to 512k or even to 1024k file size.

Assuming an SSD raid set is NTFS 4kb stripped file size, then am i correct in assuming that all the other ATTO MB/s performance metrics are not relevant?

In other words, using ATTO benchmark software, am i correct is reasoning that the only MB/s performance metric that applies to the specific SSD being measured is the the file size on ATTO which actually corresponds to (matches) the stripped file size of the disk being measured?

Jeff
Mich.
a b $ Windows 7
December 29, 2009 12:15:57 AM

Yes, the larger the test file the faster the measured transfer speed. So on a ssd raid it would be faster to have a large stripped size. Note I have not tried this but theoretically I think that what you say is correct.
m
0
l
December 29, 2009 1:01:24 PM

pjmelect said:
Yes, the larger the test file the faster the measured transfer speed. So on a ssd raid it would be faster to have a large stripped size. Note I have not tried this but theoretically I think that what you say is correct.


Thank you for responding... i posted this in three forums on toms and received only one (yours) reply, so either no one knows, or cares. i think it's a general lack of knowlege since there were many reads but only one repsonse. thanks again.

my next question is, since ssd's read and write in 4kb page size, if the stripped raid is ntfs 8kb in size, does it make sense to assume that the ssd takes 2 pages (2 x 4kb ea.) to write one raid 8kb striped file?

And if this is true, then the same would hold true for 16kb stripped file size, e.g. the ssd will take 4 pages to write 1 raid stripped file that is 16kb. does that make sense to you as well?

Thanks again.

Ultimately, i want to determine if my ssd capacity is less if i use 16kb stripped file size, instead of 4kb stripped file size. but before i get there, i am trying to understand what happens at the individual file level, e.g. the interface between the OS stripped file size and the ssd page handling (how it reads writes and erases)...

Thanks again...

Jeff MI

m
0
l
Related resources
a b $ Windows 7
December 30, 2009 12:36:57 AM

Thinking about this a bit more I don’t think that the stripped size will make much difference in the performance of a RAID of SSD drives, I forgot to take into account the effect of the cache on the SSD drive, this will if properly implemented make the stripped size irrelevant. As I said before I have not tried this as I am to poor to afford a RAID of SSD drives, so if you try this let me know here how it turns out.
m
0
l
a b $ Windows 7
December 30, 2009 12:17:33 PM

Depending your mobo / chipset you might find that two SSD's in RAID will be limited by the SATA controller for maximum read / write.
m
0
l
!