Optical drive read rate lower with DMA on

Hello,

I have some LG BD drive (BH10LS30 says M. Toolbox) that I use with a sii3112 card on AmigaOneXE - the other device is PATA HDD with an adapter. While trying to view DVD movies as best I could, I discovered only PIO modes work for that, because when I activate DMA, the read speed suffers too much. So much as to cease normal playback.

I then timed the copying of a large (25 MB if I recall it) file to RAM disk, and the time for DMA was 1.6 times that of the best PIO mode. So at first I'd like to hear if this is common with similar hardware setups, and also whether there are A1XE systems that get decent performance from SATA DVD or blu-ray drives.

I haven't determined if there's a similar performance hit for writing, but when I changed over to DMA when writing to a DVD-RAM disk with AmiDVD, the reported writing rate stayed at 1900 kilobytes per second until the finish.

My previously used optical drive is PATA and attached to the motherboard interface #2, so I obviously used PIO mode then.

Not sure if this is correct, but I think the SiI device slows down to the slowest drive attached to the card. In your case, the PATA drive with adaptor would be dragging down the speed of the DVD/BD drive to PATA range.

Paul

@Paul

The HDD gains tremendously from using "UDMA 5" compared to PIO, but I should investigate this option. Thanks for the suggestion.

Update: the HDD has been replaced with a real SATA SSD drive, but the BD drive still behaves the same: if I watch a DVD, I have to use PIO and lose precious CPU time on it.

Hello,

I have experienced similar issues regarding use of UDMA on optical drives.
However, UDMA works as expected with a harddrive, significantly offloading the CPU.
I haven't tried the PIO mode.

My opinion is that there has to be a bug somewhere in the OS.
Let's hope Hyperion will fix the issue in a future update of the OS.

To sum it up, here are my experiences with UDMA on my SATA DVD-writer:
- Write speed is limited to 5 MB/sec (using AmiDVD)
- Read speed is limited to 2.5 MB/sec (drag'n'drop copy in workbench), if the files copied is large (multiple MBs each).
- Reading & writing slows down the whole system (if CPUInfo shows only 10% CPU usage, other tasks needs significantly more time to finish compared to without the read/write process. To me, it seems like the multitasking abilities are limited while reading from/writing to a DVD media.
- If I try to access a disk partition while writing, opening the partion involves too high waiting time (a kind of "lockup").

For comparision, here are my experiences by using an external USB DVD-writer instead of the internal SATA:
- Write speed is the same as with SATA
- Read speed is max 6.2 MB/sec

In both cases, the max. speed obtained is far below the speed limits of the DVD drives themselves.


You will find more details of the issues here:
http://forum.hyperion-entertainment.biz/viewtopic.php?f=17&t=328


My system (hardware):
o ACube SAM440EP 667MHz (mini-ITX), with a SATA controller onboard (Silicon Image SII3114). It has Amiga OS4.1 update 4 installed.
o As storage, I use a 30GB OCZ SSD ("Solid series") and a 120GB OCZ SSD ("Vertex 2").
o Internal SATA DVD writer is a Plextor PX-820SA.
o External USB DVD writer is a Samsung WriteMaster SE-S224.

SATA-settings:
DVD-rom: UDMA 5, 100 MB/s
HD (Vertex 2 SSD): UDMA 6, 133 MB/s
HD (Solid series SSD): UDMA 5, 100 MB/s

Eh, something strange happended to my post, so here it is once more:

Hello,

I have experienced similar issues regarding use of UDMA on optical drives.
However, UDMA works as expected with a harddrive, significantly offloading the CPU.
I haven't tried the PIO mode.

My opinion is that there has to be a bug somewhere in the OS.
Let's hope Hyperion will fix the issue in a future update of the OS.

To sum it up, here are my experiences with UDMA on my SATA DVD-writer:
- Write speed is limited to 5 MB/sec (using AmiDVD)
- Read speed is limited to 2.5 MB/sec (drag'n'drop copy in workbench), if the files copied is large (multiple MBs each).
- Reading & writing slows down the whole system (if CPUInfo shows only 10% CPU usage, other tasks needs significantly more time to finish compared to without the read/write process. To me, it seems like the multitasking abilities are limited while reading from/writing to a DVD media.
- If I try to access a disk partition while writing, opening the partion involves too high waiting time (a kind of "lockup").

For comparision, here are my experiences by using an external USB DVD-writer instead of the internal SATA:
- Write speed is the same as with SATA
- Read speed is max 6.2 MB/sec

In both cases, the max. speed obtained is far below the speed limits of the DVD drives themselves.


You will find more details of the issues here:
http://forum.hyperion-entertainment.biz/viewtopic.php?f=17&t=328


My system (hardware):
o ACube SAM440EP 667MHz (mini-ITX), with a SATA controller onboard (Silicon Image SII3114). It has Amiga OS4.1 update 4 installed.
o As storage, I use a 30GB OCZ SSD ("Solid series") and a 120GB OCZ SSD ("Vertex 2").
o Internal SATA DVD writer is a Plextor PX-820SA.
o External USB DVD writer is a Samsung WriteMaster SE-S224.

SATA-settings:
DVD-rom: UDMA 5, 100 MB/s
HD (Vertex 2 SSD): UDMA 6, 133 MB/s
HD (Solid series SSD): UDMA 5, 100 MB/s

Ok, so this happens even with an integrated SATA controller. Thanks for the information.