How does sector size affect HDD performance?

[Alvin Smith]

This question is applied to a pair of Spinpoint F3 1TB media content render drives (one is "read from" and the other is "render to") . . .

These drives will have "short" scratch partitions on outer tracks.

This will be my first installation of Win7-Pro 64-Bit.

3 Questions:

(1) Will I have the opportunity to define sector size ?

(2) What effect will sector size have on "short partition" performance ?

(3) If I can/choose a larger sector size for outer partition, am I stuck with that (same) sector size for all partitions on the physical disk?


Thanks!

= Alvin =

 

[sub mesa]

No. Normal HDDs use 512-byte sectors. Only disks with Advanced Format like the new "EARS" WD drives use 4KiB sectors.

The higher the sector size, the more bandwidth/performance wasted when only updating a tiny bit in the sector; i.e. writing 2 bytes with 4KiB sector size means you actually read 4KiB then write 4KiB - total 8KiB of physical I/O for just writing 2 bytes.

 

[geofelt]

1) No, The sector size is fixed by the drive microcode.
2) It depends. On balance, not a significant difference. On short(<4k) operations, perhaps a bit slower, on longer perhaps a bit faster.
3) A moot point if you can't pick.

The outer tracks of a hard drive are longer and contain more data per track than the inner tracks. Given a 7200rpm rotation rate, the outer tracks can transfer data at a higher rate, making them better performers.

4k sectors have larger overhead per sector, but there are fewer sectors per track, resulting in more useful data per track.

If you are interested in maximum performance out of conventional hard drives, look at the new WD velociraptor 600gb drives: http://www.newegg.com/Product/Product.aspx?Item=N82E16822136555