I have a RAID5 array built from 4 1TB drives. I initially set the stripe size to 1M since I will be storing large files (much larger than 1MB). The NTFS cluster size is 64KB (largest possible). However, seeing the statistics made me reconsider my choice.
The software is relatively stupid and only has on 1 thread with QD=1, so for reads (this array will be mostly read) I will get an SSD and use that as cache. I won't be using that for writing, leaving only the internal cache of the controller (Adaptec 5805Z).
Still, I would like to get the best performance from this array.
So, the statistics (I can see them using Adaptec Storage Manager) say that for reading, 64KB, 128KB and 256KB are most common with 128KB taking first place (the software reads in 128K blocks). There were zero 512K or 1M reads. With writes, 256K is most common, 128K taking second place.
The question: Will changing the stripe size to 256K or 128K (or lower) speed up the array considering the statistics? Would that slow down the rebuild of the array?