Syschkio (onstat -D)
View syschkio: Lists I/O statistics by chunk
chunknum smallint, chunk number
reads integer, number of read ops
pagesread integer, number of pages read
writes integer, number of write ops
pageswritten integer, number of pages written
mreads integer, number of mirror read ops
mpagesread integer, number of mirror pages read
mwrites integer, number of mirror write ops
mpageswritten integer number of mirror pages written