funnyface
Posts: 3
Joined: Sat Aug 30, 2014 2:38 pm

Extremely low performance with external USB exfat HDD

Sat Aug 30, 2014 2:55 pm

Man, i love Raspbmc.

works great except of very slow performance with the USB exfat format HDD i connected.
copying a file inside the HDD or from/to the network yields extremely poor speed, even for USB2.
it has a separate power supply.

both partitions of this HDD are not mentioned on the fstab so i guess they are loaded automatically.
these how the disk looks with mount -l

Code: Select all

/dev/sda2 on /media/New Volume type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096) [New Volume]
/dev/sda3 on /media/New Volume_ type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096) [New Volume]
any ideas why this is the case and what can i do to solve this ?

elatllat
Posts: 1337
Joined: Sat Dec 17, 2011 5:05 pm

Re: Extremely low performance with external USB exfat HDD

Wed Sep 03, 2014 3:22 am

quantify?

17MB/s is the max imposed by network and drive both on USB 2.
http://en.wikipedia.org/wiki/USB#USB_2.0
SBC with 32GB RAM: https://hardkernel.com

FAQ : https://raspberrypi.stackexchange.com

Unanswered: https://www.raspberrypi.org/forums/search.php?search_id=unanswered

User avatar
AndrewS
Posts: 3625
Joined: Sun Apr 22, 2012 4:50 pm
Location: Cambridge, UK
Contact: Website

Re: Extremely low performance with external USB exfat HDD

Wed Sep 03, 2014 3:31 am

Linux (especially on the Pi) always has slow read/write speeds to exFAT or NTFS filesystems, because they're implemented as user-mode filesystem drivers, rather than kernel-mode (because of the patents etc. Microsoft has on them).

The 'fix' is to reformat your HDD with a Linux-native filesystem such as ext4. Which may or may not be an option depending if you need to use the HDD with non-Linux systems too...

elatllat
Posts: 1337
Joined: Sat Dec 17, 2011 5:05 pm

Re: Extremely low performance with external USB exfat HDD

Wed Sep 03, 2014 3:46 am

you can use "top" to see it you are CPU bound.
SBC with 32GB RAM: https://hardkernel.com

FAQ : https://raspberrypi.stackexchange.com

Unanswered: https://www.raspberrypi.org/forums/search.php?search_id=unanswered

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