/sys directory is generally where the sysfs filestystem is mounted, which contains information about devices and other kernel information.
The files in
/sys/block contain information about block devices on your system. Your local system has a block device named
/sys/block/sda exists. Your Amazon instance has a device named
/sys/block/<dev>/stat file provides several statistics about the state of block device
<dev>. It consists of a single line of text containing 11 decimal values separated by whitespace:
Name units description
---- ----- -----------
read I/Os requests number of read I/Os processed
read merges requests number of read I/Os merged with in-queue I/O
read sectors sectors number of sectors read
read ticks milliseconds total wait time for read requests
write I/Os requests number of write I/Os processed
write merges requests number of write I/Os merged with in-queue I/O
write sectors sectors number of sectors written
write ticks milliseconds total wait time for write requests
in_flight requests number of I/Os currently in flight
io_ticks milliseconds total time this block device has been active
time_in_queue milliseconds total wait time for all requests
So, each block device will have its own
statistics file, hence the different values.
See kernel docs for more details.