[SOLVED] Slow SATA / No DMA?

[mykec]

Hello,

My first and, until now, only DVD-Writer died yesterday. It was purchased new in April 2005. I burned many hundreds of DVD-Rs with it. It will be missed. It was an IDE DVD-Writer with Molex power connector. I have replaced it with a low-cost Lite-On 24x Writer with SATA power and SATA data connectors. The first thing I noticed about it is how it burns a 4.2GB DVD-R in 10 minutes as opposed to 6 minutes like my previous IDE burner. Also, when I simply copy a 4.2GB DVD to my internal hard drive, it initially says the copy process will require some 36-40 minutes to complete! The initial speed is 1.9MB/s. Curiously, however, after a few minutes the speed gradually increases to the same 5.9MB/s I was accustomed to with my previous drive.

My first guess is that DMA was not "on" for this drive - but after extensive Googling for info, there seems to be a consensus that DMA is only useful with IDE drives. It appears that many people have had problems with slow SATA drives and Linux during the past 3 years - but solutions are proving elusive.

What can I do to bring this new SATA drive up to par with the performance with which I have grown accustomed over the past (nearly) 5 years?

I am a generally elated Linux Mint 7 user, btw.

Myke

[optimize me]

There's a lot of hot air blowing around in this discussion at UF, but you may be able to find some info that helps you in there. Some of the solutions work for some people, some don't.. you might have some luck.

I've been fighting the SATA/USB bug for over a year now, and there's no real progress being made. While there is some evidence to the contrary, it seems the bug is Ubuntu (and therefore all of its' derivatives) specific - I don't know of anyone who did their own Debian install and who has the problems.

Good luck.

[DrHu]

https://bugs.launchpad.net/ubuntu/+sour ... bug/119730
possibly setting drives in BIOS might help..

Some notebooks, others besides Ubuntu or derivations of..
http://www.thinkwiki.org/wiki/Problems_ ... _and_Linux

Linux kernels prior to 2.6.16 (ata_piix) and 2.6.19 (ahci) do not support suspend and resume for SATA devices. As a result, the machine hangs upon the first disk access after resume. A kernel patch (LKML posting) fixes this by adding SATA power management support.
Kernel 2.6.16 and later fixes this problem for most systems.

http://www.linuxquestions.org/questions ... do-377370/
http://linuxmafia.com/faq/Hardware/sata.html

"libata": This is the newer ATA driver set for selected SATA chipsets only, maintained by Jeff Garzik, leveraging the kernel's well-tested SCSI layer. Garzik developed it in the 2.6 kernel series. 2.4 support was available only with a backported patch until libata's inclusion in 2.4.27 and later.

libata causes each SATA port appear as a new SCSI bus. There are individual low-level drivers for the individual SATA chipsets, e.g., ahci, pdc_adma, ata_piix, sata_nv, sata_mv, sata_promise, sata_qstor, sata_sil, sata_sil24, sata_sis, sata_sx4, sata_uli, sata_svw, sata_via, sata_vsc.

[mykec]

~$ uname -r
2.6.28-11-generic

It would seem that my current kernel contains these fixes. Hmmm...

[DrHu]

I doubt it would improve anything, but the latest kernel available seems to be 2.6.28-15
In terminal, check

uname -r
2.6.28-15-generic

You can get that via synaptic, mint menu>System>Package manager

• Reload
  --to update resources list, like apt-get update in terminal
• Mark all upgrades
  --like apt-get upgrade in terminal
• Apply
  --apply (execute) changes as marked
• Reboot
  --to enable the new kernel selection in the grub menus; wait until synaptic indicates success. You can also watch the details in the synaptic terminal disply if you wished..

[bulwnkl]

Are you running an AMD processor or Intel? If AMD, is your motherboard and nVidia nForce, or something else?

[mykec]

I'd completely forgotten about this thread until I saw it again tonight. I've been using that drive for 4 years now and cannot recall the last time I've encountered a slowness issue with it. It still burns a 4.7GB DVD-R in 10 minutes - but that's because I now verify every disc I burn whereas before I would only burn and take my chances. I eventually learned that's not very smart when I encountered some bad discs I didn't previously realize had problems.

Anyway... I guess this issue could be marked "SOLVED" but I don't really know what the solution was and don't recall actually implementing one. The drive's been fine for a long time now - although it too is beginning to show it's age like the previous one which died after only 4 years of my constant abuse! LOL