Linux I/O size
Hi,
I've been looking at I/O perofrmance statistics of an Oracle database and I'm trying to figure out how Oracle database I/O operations are translated to storage I/O requests. Oracle multiblock size is configured to 1M, ASM is used with allocation unit = 1M. So In my point of view - seems best to send 1MB I/O requests to storage when doing multiblock reads or writes. Looking at iostat statistics - average request size seemed lower so I tried the following simpler experiment (no other users of that disk device at that moment):
# time dd if=/dev/sdak bs=1024k of=/dev/null iflag=direct
I've been looking at I/O perofrmance statistics of an Oracle database and I'm trying to figure out how Oracle database I/O operations are translated to storage I/O requests. Oracle multiblock size is configured to 1M, ASM is used with allocation unit = 1M. So In my point of view - seems best to send 1MB I/O requests to storage when doing multiblock reads or writes. Looking at iostat statistics - average request size seemed lower so I tried the following simpler experiment (no other users of that disk device at that moment):
# time dd if=/dev/sdak bs=1024k of=/dev/null iflag=direct
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