On Sun, Sep 29, 2019 at 11:46:07AM -0400, D. Hugh Redelmeier via talk wrote:
I bought some inexpensive SanDisk Cruzer Glide 16GB USB sticks from Walmart last year. Cheap.
Today I copied the CentOS 8 installation image onto one.
time sudo dd if=CentOS-8-x86_64-1905-dvd1.iso of=/dev/sdg oflag=direct bs=16M
(I used a USB 3 port on my dessktop.)
It seemed to take a long time, so I did this to see if anything was happening (the dd process' PID was 29047):
sudo kill -s USER1 29047
Yes, there was progress, but not as much as I would expect. The final statistics were:
425+1 records in 425+1 records out 7135559680 bytes (7.1 GB, 6.6 GiB) copied, 1560.63 s, 4.6 MB/s
real 26m4.152s user 0m0.072s sys 0m4.706s
This amounts to about 4.56 MB/s. That's even less than the poor Average Sustained Write Speed 7.64 MB/s reported here:
<https://usb.userbenchmark.com/SpeedTest/2718/SanDisk-Cruzer-Glide>
Note: this stick hasn't been written to often. It should not be near the end of its life (that could slow down a flash device).
I have encountered Kinston USB3 sticks that are incredibly slow too. Some of the cheap drives are complete garbage. -- Len Sorensen