Compaq HSZ80 manual Increasing Sequential Write Performance, Maximum Chunk Size for RAIDsets

3–54Creating Storagesets

Increasing Sequential Write Performance

For stripesets (or striped mirrorsets), use a large chunk size relative to the I/O size to increase the sequential write performance. A chunk size of 256 generally works well.

Chunk size does not significantly affect sequential read performance.

Maximum Chunk Size for RAIDsets

Do not exceed the chunk sizes shown in Table 3–4for a RAIDset. The maximum chunk size is derived by 2048/(d – 1) where d is the number of disk drives in the RAIDset.

Table 3–4 Maximum Chunk Sizes for a RAIDset

RAIDset Size	Maximum Chunk Size
3 members	1024 blocks
4 members	682 blocks
5 members	512 blocks
6 members	409 blocks
7 members	341 blocks
8 members	292 blocks
9 members	256 blocks
10 members	227 blocks
11 members	204 blocks
12 members	186 blocks
13 members	170 blocks
14 members	157 blocks