Data Fever: Ultra320 SCSI from Adaptec and LSI Logic

I/O Performance

With the smaller block sizes, the transfer rates are less interesting. The I/O performance is what's meaningful here.

LSI's 20320R is able to maintain an ever so slight lead over the Adaptec controller up to a queue depth of 16 blocks. Starting with 32 accesses in direct succession, however, the Adaptec 39320D-R increases its tempo further, while the LSI's performance starts to lag somewhat.

With 4 kB blocks, it's a similar picture. The only thing that changes is that the performance of the LSI lags somewhat more.

Blocks of 8 kB bring the same results as with 4 kB - except the values are slightly less.