WARNING: WRITE_DMA UDMA IRCR error

[Markus Schanovsky]

Hello!
I have a new am464-Box running FreeBSD 5.2.1 with a serial ATA-Disk of 160 GB.
 From the beginning I encountered errors like :
Mar 26 09:02:04 free kernel: ad4: WARNING - WRITE_DMA UDMA ICRC error 
(retrying request) LBA=118
166239
Mar 26 09:02:25 free kernel: ad4: WARNING - WRITE_DMA UDMA ICRC error 
(retrying request) LBA=118
169055
................
There was no other problem, not loss of data - the machine seems very fast, 
compiling of ports was quick and successfull.

I tried to use a small serial-ata-disk - with the same errors.

Is it a serious problem running FreBSd with this errors? may some data be 
lost sometime in the future?

Now I solved the problem with sysctl hw.ata.ata_dma = 0 in my 
/boot/loader.conf - there are no write errors further.
But what's the disadvantage of turning ata_dma off?
Speed?

Please give me some hints!
With best regards
Mark


----------
Markus Schanovsky
Paedagogisches Institut der Stadt Wien                       EDV-Administrator
Burggasse 14-16/214                                     Tel: +43-1/523 62 
22/99 222
A-1070 Vienna                                            Fax: +43-1/523 62 
22/99 93 200
Austria
email: m.schanovsky at m56ssr.wien.at       priv: markus at schanovsky.at
Website: http://www.pi-wien.at