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
Dell EMC 092GD6 Broadcom 9305-16i LSI Quad Port 4 Port SAS RAID Controller
$84.99
Dell PERC H330 PCIe 3.0 x8 RAID Storage Controller 4Y5H1 High Profile
$15.99
Yottamaster 2 Bay RAID Hard Drive Enclosure USB 3.1 For 2.5" SATA HDD SSD UASP
$56.25
ORICO 5 Bay Raid USB3.0 to SATA External Hard Drive Enclosure for 3.5'' HDD LOT
$31.99
Inspur LSI YZCA-00424-101 Raid Card 12Gbps HBA Controller Low Profile 9300-8i IT
$15.98
LSI MegaRAID 9361-8i 12Gbps PCIe 3 x8 SATA SAS 3 8 Port RAID + BBU & CacheVault
$39.00
LSI 8 Port 6Gbps PCIe 3.0 External SAS RAID Card w/ 1GB CacheVault & Low Profile
$26.10
9207-8i PCIE3.0 6Gbps HBA LSI FW:P20 IT Mode ZFS FreeNAS unRAID 2* SFF-8087 US
$32.88
Yottamaster 2 Bay RAID Hard Drive Enclosure USB 3.1 Type B For 3.5" SATA HDDs
$69.91
HDD Enclosure USB 3.0 2.5 inch Dual Bay 2*6TB HDD RAID SATA Hard Drive Enclosure
$32.69