Messages in this thread | | | Subject | Re: 2.4.21 ServerWorks DMA Bugs | From | Markus Plail <> | Date | Sat, 05 Jul 2003 09:21:13 +0200 |
| |
On Fri, 4 Jul 2003, Ryan Mack wrote:
> I've real the other threads but nothing touches on my specific issue. > I have a dual P4 Xeon Dell PowerEdge 1600SC with a Fusion MPT SCSI > controller and a ServerWorks CSB5 IDE chipset. All the HDs are on the > SCSI bus, and only my CD reader and my DVD writer are on the IDE bus > (one on each channel). Hyperthreading is enabled (4 logical > processors). I am using GCC 3.2.2. > > The CD readers is the blacklisted 'SAMSUNG CD-ROM SC-148C' and I never > use it so I can remove it if needed. The DVD writer is a 'SONY DVD RW > DRU-500A'. Both are going through the ide-scsi driver. Whenever I > read/write CDs in the DVD writer, I get very high system load (50% on > one CPU), even though DMA seems to be enabled.
If you are writing CDs with unusual block sizes (audio CDs, (S)VCDs, RAW mode -> blocksize != 2048) you won't get DMA with ide-scsi, no matter what you do. It's simply not supported.
regards Markus
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |