On 1/15/07, kenneth johansson <ken@xxxxxxxxx> wrote:
On Mon, 2007-01-15 at 18:13 +0900, Tejun Heo wrote:
> kenneth johansson wrote:
> > I changed my bios setting for SATA from IDE to AHCI.
> >
> > This resulted in some "interesting" read throughput.
> >
> > plots can be found at http://kenjo.org/~ken/sata/
> > The plots was done on a live disk so some noise is expected but in the
> > ahci mode the throughput get stuck at 17 MB way to much.
>
> It's probably not an ahci problem but more of NCQ implementation problem
> in the drive firmware. Please report the result of 'hdparm -I /dev/sdX'
> and try adjust queue depth and see what happens.
>
> http://linux-ata.org/faq.html
>
It was, when I turn of NCQ with "echo 1
> /sys/block/sda/device/queue_depth" I get the same performance as when
the BIOS is set to IDE.
I though that NCQ was intended to increase performance ??
also the disk is a Westen Digital raptor and it's probably the most
benchmarked drive one could get so I was not expecting a problem with
the drive.
My Raptor drive WDC WD740ADFD-00 Rev: 20.0 performs worse with NCQ
than with NCQ, Alan Cox has added it to a blacklist but I dont think
that is in the mainline kernel yet.
Search the list archives for my previous postings about it, including
some hdparm -tT results.
Andy
-------
ATA device, with non-removable media
Model Number: WDC WD1500ADFD-00NLR1
Serial Number: WD-WMAP41269747
Firmware Revision: 20.07P20
Standards:
Used: ATA/ATAPI-7 published, ANSI INCITS 397-2005
Supported: 7 6 5 4
Configuration:
Logical max current
cylinders 16383 16383
heads 16 16
sectors/track 63 63
--
CHS current addressable sectors: 16514064
LBA user addressable sectors: 268435455
LBA48 user addressable sectors: 293046768
device size with M = 1024*1024: 143089 MBytes
device size with M = 1000*1000: 150039 MBytes (150 GB)
Capabilities:
LBA, IORDY(can be disabled)
Queue depth: 32
Standby timer values: spec'd by Standard, with device specific
minimum
R/W multiple sector transfer: Max = 16 Current = 16
Recommended acoustic management value: 128, current value: 254
DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5
*udma6
Cycle time: min=120ns recommended=120ns
PIO: pio0 pio1 pio2 pio3 pio4
Cycle time: no flow control=120ns IORDY flow control=120ns
Commands/features:
Enabled Supported:
* SMART feature set
Security Mode feature set
* Power Management feature set
* Write cache
* Look-ahead
* Host Protected Area feature set
* WRITE_BUFFER command
* READ_BUFFER command
* NOP cmd
* DOWNLOAD_MICROCODE
Power-Up In Standby feature set
* SET_FEATURES required to spinup after power up
SET_MAX security extension
* Automatic Acoustic Management feature set
* 48-bit Address feature set
* Device Configuration Overlay feature set
* Mandatory FLUSH_CACHE
* FLUSH_CACHE_EXT
* SMART error logging
* SMART self-test
* General Purpose Logging feature set
* SATA-I signaling speed (1.5Gb/s)
* Native Command Queueing (NCQ)
* Host-initiated interface power management
* Phy event counters
DMA Setup Auto-Activate optimization
* Software settings preservation
* SMART Command Transport (SCT) feature set
* SCT Long Sector Access (AC1)
* SCT LBA Segment Access (AC2)
* SCT Error Recovery Control (AC3)
* SCT Features Control (AC4)
* SCT Data Tables (AC5)
unknown 206[12]
Security:
Master password revision code = 65534
supported
not enabled
not locked
frozen
not expired: security count
not supported: enhanced erase
Checksum: correct
-
To unsubscribe from this list: send the line "unsubscribe linux-ide" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
-
To unsubscribe from this list: send the line "unsubscribe linux-ide" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
