Download/write speed very slow

[Wesso]

Hi there,

I bought i WD Elements USB 3.0 500 GB hard disk to download data on via NZBGet 9.0 which I compiled. I formatted the hard disk to Ext3 and set the download path of NZBGet to my /media/usb/ mountpoint.

I am achieving speeds of 800 Kbytes per second where is should achieve 6 MBytes per second. Is it just a hardware limitation or did i do something wrong?

Greetings,
Wesso

[CurlyMo]

Remember that the RPi only has 2 USB 2.0 ports, so tranfser speeds will be noticably slower than USB 3.0

[Wesso]

Yeah i know this, still i should be able to get more speed then what i have now right?

[Koenkk]

This is indeed a bit slow, can you do a test with EXT4 or NTFS?

[Wesso]

NTFS performs very slow, 300 KBytes and Ext4 similar to Ext3 performance, around 800 Kbytes

[BartOtten]

It seems like the transferrate is limited by CPU power as NTFS is so much slower. As NTFS is a CPU-intensive filesystem...the CPU might be the bottleneck. However, 800kb/sec is far to slow afaik. Will test my diskspead later today. Sun is watching Finding Nemo

[Enigmach]

I used SabNZBd with NTFS and could reach higher speeds, typically above 800 kb/s although it was fluctuating a lot. I'm currently compiling NZBGet since it's less CPU-heavy so that should give a nice comparison. For comparison purposes, what is the brand and class of your SD-card?

[Enigmach]

Update: Currently obtaining downloadspeeds of 1.1 MB/s (which is my max) with NZBGet, a class 10 SD-card and a 2TB NTFS disk. I'll check later how it runs if I add sickbeard and couchpotato, but it seem that the 300 KBytes you get with your NTFS disk is not necessarily a CPU limitation.

Edit: It seems that I had directed it to a wrong folder, so the 1.1 MB/s was on my SD-card. Currently getting ~375 - 435 KB/s, so I'll be looking for a solution as well

[Pixarr]

(28th Dec, 2012 08:56 PM)Enigmach Wrote:  Update: Currently obtaining downloadspeeds of 1.1 MB/s (which is my max) with NZBGet, a class 10 SD-card and a 2TB NTFS disk. I'll check later how it runs if I add sickbeard and couchpotato, but it seem that the 300 KBytes you get with your NTFS disk is not necessarily a CPU limitation.

Edit: It seems that I had directed it to a wrong folder, so the 1.1 MB/s was on my SD-card. Currently getting ~375 - 435 KB/s, so I'll be looking for a solution as well

I have exacly the same problem with my 2tb NTFS disk, around the 500 KB/s. When i transfer on my SD-Card speed is around 1.1 MB/s as well.

[Enigmach]

Based on this: http://www.readynas.com/forum/viewtopic.php?f=36&t=48722 it would seem a CPU issue. The NAS mentioned uses an ARM processor clocked at 1.6 GHz and gets 600 KB/s with NTFS disks. Other sources also report download speeds of max ~550 KB/s for the RPi so this might be the max for NTFS disks.

[Wesso]

Small update: I have installed RaspBMC on the same kind of SD card, put it in the same raspberry, compiled NZBGet 9.0... I can now download up to 4.5 MBytes/s, definitely a improvement. Not sure what the bottleneck in Xbian could be.

[namtih]

I would like to compare it with my configuration. To make it independent from programs like NZBGet please use these commands:

Code:

#to get the /dev path of your hd, mostly /dev/sda1
df

#run the short test
sudo hdparm -Tt /dev/sda1

[Wesso]

This test only tests the read speed, but here you go:

Timing cached reads: 308 MB in 2.00 seconds = 153.62 MB/sec
Timing buffered disk reads: 70 MB in 3.01 seconds = 23.25 MB/sec

Keep in mind, its for my kind of working XBMC setup with RaspBMC and an Ext4 external via usb powered usb disk. Also to get more memory free for downloading I stopped XBMC.

Also, if you are using a SSL connection with your NZBGet it will go allot slower then without it. Just a tip.

[namtih]

(30th Dec, 2012 08:55 AM)Wesso Wrote:  This test only tests the read speed, but here you go:

Good point ;-)
Second try:

Code:

#get /dev path and mount point of your USB drive, mostly /dev/sda1 and /media/usb0
df
/dev/sda1      1953503968 1711042516 242461452  88% /media/usb0

#Read test
sudo hdparm -t /dev/sda1
/dev/sda1:
Timing buffered disk reads:  70 MB in  3.00 seconds =  23.29 MB/sec

#Write test - will create a 500mb file
cd /media/usb0
dd if=/dev/zero of=500mb.bin bs=1M count=500 oflag=direct
500+0 records in
500+0 records out
524288000 bytes (524 MB) copied, 17.6986 s, 29.6 MB/s

#Delete the 500mb test file
rm 500mb.bin

Read: 23.29 MB/sec
Write: 29.60 MB/sec
NTFS, XBMC was stopped before.

[BartOtten]

Read: 21.60 MB/sec
Write: 26.0 MB/s