I got a new external crucial X8 usb 3.0 ssd and it reports a very large blocksize.
Unfortunately, it seems to make playing videos over the network with samba have problems. It may also be suboptimal using it on a usb 2.0 port.
blockdev --report
shows most drives have 256 sector readahead
RO RA SSZ BSZ StartSec Size Device
ro 256 512 1024 0 205111296 /dev/loop0
ro 256 512 1024 0 204873728 /dev/loop1
ro 256 512 1024 0 4096 /dev/loop2
ro 256 512 1024 0 157855744 /dev/loop3
however, my crucial ssd gets a giant 131072 readahead value. I believe this is what's causing the problems with the network drive sharing.
sudo blockdev --setra 16384 /dev/sdb
sets it to a much better value and I don't see the audio dropouts.
You can also check the value by getting the readahead for a specific drive.
blockdev --getra /dev/sdb
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