Comment 44 for bug 422994

Ok, I've done it (on a productivity server, don't blamed me ;-) )

I've this chipset :

01:07.0 RAID bus controller: VIA Technologies, Inc. VT6421 IDE RAID Controller (rev 50)
 Subsystem: VIA Technologies, Inc. VT6421 IDE RAID Controller
 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
 Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
 Latency: 32
 Interrupt: pin A routed to IRQ 19
 Region 0: I/O ports at a400 [size=16]
 Region 1: I/O ports at a800 [size=16]
 Region 2: I/O ports at ac00 [size=16]
 Region 3: I/O ports at b000 [size=16]
 Region 4: I/O ports at b400 [size=32]
 Region 5: I/O ports at b800 [size=256]
 [virtual] Expansion ROM at 300a0000 [disabled] [size=64K]
 Capabilities: <access denied>
 Kernel driver in use: sata_via
 Kernel modules: sata_via

This hardrive on the SATA connector :

        Model Family: Western Digital Caviar Second Generation Serial ATA family
        Device Model: WDC WD5000AAKS-00V1A0
        Serial Number: WD-WCAWF2903335
        Firmware Version: 05.01D05
        User Capacity: 500 107 862 016 bytes
        Device is: In smartctl database [for details use: -P show]
        ATA Version is: 8
        ATA Standard is: Exact ATA specification draft version not indicated
        Local Time is: Tue Sep 14 12:39:19 2010 CEST
        SMART support is: Available - device has SMART capability.
        SMART support is: Enabled

Now this kernel : 2.6.32-25-generic #43-Ubuntu SMP Wed Sep 1 09:46:39 UTC 2010 i686 GNU/Linux

And it *seems* to not have the usually annoying messages like « ata3.00: cmd 25/00:60:bd:ad:41/00:00:1a:00:00/e0 tag 0 dma 49152 i ... blablabla »

It seems also ti have improve the drive speed :
BEFORE :
/dev/sdc:
 Timing cached reads: 718 MB in 2.00 seconds = 359.02 MB/sec
 Timing buffered disk reads: 20 MB in 3.61 seconds = 5.55 MB/sec
AFTER :
/dev/sdc:
 Timing cached reads: 754 MB in 2.00 seconds = 376.38 MB/sec
 Timing buffered disk reads: 168 MB in 3.01 seconds = 55.81 MB/sec

Wow ! 10x faster !

Thank a lot for the fix guys !