Bug 99481

Summary:	reading speed is too slow
Product:	[Applications] k3b	Reporter:	Tom Malfrere <tom.malfrere>
Component:	general	Assignee:	Sebastian Trueg <trueg>
Status:	RESOLVED FIXED
Severity:	normal	CC:	mail, mecirt
Priority:	NOR
Version First Reported In:	unspecified
Target Milestone:	---
Platform:	unspecified
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	log of a cd copy attempt

Description Tom Malfrere 2005-02-15 22:33:03 UTC

Version:           0.11.20 (using KDE 3.3.0, SuSE)
Compiler:          gcc version 3.3.4 (pre 3.3.5 20040809)
OS:                Linux (i686) release 2.6.8-24.11-default

I have a 52x CDROM and a 40x plextor.
When I start an 'on the fly copy' the reading speed is much too slow, the write buffer is exhausted within seconds and burnproof is activated.
It takes ages to complete the write. Even with a copy to disk it remains very slow.
I tried an on-the-fly copy at 8x and even then the write buffer gets exhausted...

The same hardware is able to copy CD's on-the-fly at 32x speed under windows.
Why isn't it working under linux?

Comment 1 Tom Malfrere 2005-02-15 22:34:21 UTC

Created attachment 9652 [details]
log of a cd copy attempt

Comment 2 Sebastian Trueg 2005-02-17 08:39:53 UTC

dma enabled?
plextor writer and a 2.6.8 kernel... well, probably the worst combination for CD writing on Linux.

Comment 3 Martin Chladek 2005-03-05 16:29:07 UTC

I have the same problem, but with Sony writer, kernel 2.4 and KDE 3.3 on SuSE 8.2.
It's very slow to copy CD with K3b, but normal reading is fine. I can make an image of CD with 'dd -if=/dev/cdrom -of=image.iso' and it's done with CDROM full speed.

Comment 4 Tomas Mecir 2005-03-27 18:57:59 UTC

Same problem here. Teac 48x burner.
Reading using k3b is slow, as in super-slow. Changing the reading option from read 128-times to read once helps a bit, but it's still way too slow - 0.5 MB / sec or so.
things like
cp /dev/sr0 /somewhere/blah.iso
work perfectly - about 15 MB / sec

Mandrake 10.1, kernel 2.6.8.1, KDE 3.3, K3b 0.11.20

Comment 5 Sebastian Trueg 2005-03-27 20:32:02 UTC

K3b is faster than dd here but I am using the cvs version which sets the read speed to maximum before reading so most likely this problem is solved already. :)

Comment 6 Christoph Burger-Scheidlin 2006-09-10 03:02:58 UTC

Could you please check if this bug still occurs with the recent version of k3b 
(0.12.17), please close if fixed.

Comment 7 Christoph Burger-Scheidlin 2006-11-11 18:19:10 UTC

This bug is still UNCONFIRMED, was filed for an old version of k3b (<0.12) and has not been replied to for 30 days.

Closing this bug.