Extra Poor SATA performances

[paoletto]

Hardware:

Via KT600 based motherboard (a7v600)
Wester Digital SATA hard drive

Software:

Ubuntu Hardy (before it was gutsy, but it was the same)
Kernel 2.6.24 from ubunty gutsy
or
Kernel 2.6.24.4 self compiled
(same behaviour and results)


What happens:

The machine shows the signs of PIO mode on the old IDE drives.

What i mean? well, hdparm -tT shows good values, but effective operations
on the drive raise the cpu load (on top, under the voice "wait") and i can achieve performances like 5mb/sec with the machine almost frozen


Examples:

# time cat /local/movies/Cult/Il\ nome\ della\ Rosa.avi >/dev/null

real 2m41.562s
user 0m0.040s
sys 0m3.750s

# ls -la /local/movies/Cult/Il\ nome\ della\ Rosa.avi
-rw-r--r-- 1 root root 856510464 2008-01-03 14:32 /local/movies/Cult/Il nome della Rosa.avi

(it means roughly 5Mb/sec)

in the meanwhile, "top" says:
Cpu(s): 0.3%us, 2.3%sy, 0.0%ni, 0.0%id, 97.4%wa, 0.0%hi, 0.0%si, 0.0%st


BUT:

# hdparm -tT /dev/sda

/dev/sda:
Timing cached reads: 440 MB in 2.00 seconds = 220.02 MB/sec
Timing buffered disk reads: 188 MB in 3.03 seconds = 62.14 MB/sec

so here the drive seems fast, AND dmesg says:

Apr 28 20:36:55 rivendell kernel: [ 32.111204] ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
Apr 28 20:36:55 rivendell kernel: [ 32.111363] VP_IDE: IDE controller (0x1106:0x0571 rev 0x06) at PCI slot 0000:00:0f.1
Apr 28 20:36:55 rivendell kernel: [ 32.111415] ACPI: PCI Interrupt 0000:00:0f.1[A] -> GSI 20 (level, low) -> IRQ 16
Apr 28 20:36:55 rivendell kernel: [ 32.111436] VP_IDE: not 100% native mode: will probe irqs later
Apr 28 20:36:55 rivendell kernel: [ 32.111455] VP_IDE: VIA vt8237 (rev 00) IDE UDMA133 controller on pci0000:00:0f.1
Apr 28 20:36:55 rivendell kernel: [ 32.111468] ide0: BM-DMA at 0x7800-0x7807, BIOS settings: hdaio, hdbio
Apr 28 20:36:55 rivendell kernel: [ 32.111492] ide1: BM-DMA at 0x7808-0x780f, BIOS settings: hdcMA, hddio
Apr 28 20:36:55 rivendell kernel: [ 33.336051] hdd: IRQ probe failed (0xfffffcfe)
Apr 28 20:36:55 rivendell kernel: [ 33.655836] hdd: IRQ probe failed (0xfffffcfe)
Apr 28 20:36:55 rivendell kernel: [ 34.635133] hdc: LITE-ON LTR-52327S, ATAPI CD/DVD-ROM drive
Apr 28 20:36:55 rivendell kernel: [ 34.635355] hdc: UDMA/33 mode selected
Apr 28 20:36:55 rivendell kernel: [ 34.635535] ide1 at 0x170-0x177,0x376 on irq 15
Apr 28 20:36:55 rivendell kernel: [ 35.245742] hdc: ATAPI 52X CD-ROM CD-R/RW drive, 2048kB Cache
Apr 28 20:36:55 rivendell kernel: [ 35.245755] Uniform CD-ROM driver Revision: 3.20
Apr 28 20:36:55 rivendell kernel: [ 35.248585] Driver 'sd' needs updating - please use bus_type methods
Apr 28 20:36:55 rivendell kernel: [ 35.248668] Driver 'sr' needs updating - please use bus_type methods
Apr 28 20:36:55 rivendell kernel: [ 35.249131] ACPI: PCI Interrupt 0000:00:0f.0[B] -> GSI 20 (level, low) -> IRQ 16
Apr 28 20:36:55 rivendell kernel: [ 35.249203] sata_via 0000:00:0f.0: routed to hard irq line 0
Apr 28 20:36:55 rivendell kernel: [ 35.249449] scsi0 : sata_via
Apr 28 20:36:55 rivendell kernel: [ 35.249597] scsi1 : sata_via
Apr 28 20:36:55 rivendell kernel: [ 35.252255] ata1: SATA max UDMA/133 cmd 0x9800 ctl 0x9400 bmdma 0x8400 irq 16
Apr 28 20:36:55 rivendell kernel: [ 35.252263] ata2: SATA max UDMA/133 cmd 0x9000 ctl 0x8800 bmdma 0x8408 irq 16
Apr 28 20:36:55 rivendell kernel: [ 35.454498] ata1: SATA link down 1.5 Gbps (SStatus 0 SControl 300)
Apr 28 20:36:55 rivendell kernel: [ 35.674349] ata2: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
Apr 28 20:36:55 rivendell kernel: [ 35.880105] ata2.00: ATA-7: WDC WD10EACS-00ZJB0, 01.01B01, max UDMA/133
Apr 28 20:36:55 rivendell kernel: [ 35.880113] ata2.00: 1953525168 sectors, multi 16: LBA48 NCQ (depth 0/32)
Apr 28 20:36:55 rivendell kernel: [ 35.914627] ata2.00: configured for UDMA/133
Apr 28 20:36:55 rivendell kernel: [ 35.914830] scsi 1:0:0:0: Direct-Access ATA WDC WD10EACS-00Z 01.0 PQ: 0 ANSI: 5
Apr 28 20:36:55 rivendell kernel: [ 35.915133] sd 1:0:0:0: [sda] 1953525168 512-byte hardware sectors (1000205 MB)
Apr 28 20:36:55 rivendell kernel: [ 35.915164] sd 1:0:0:0: [sda] Write Protect is off
Apr 28 20:36:55 rivendell kernel: [ 35.915211] sd 1:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
Apr 28 20:36:55 rivendell kernel: [ 35.915319] sd 1:0:0:0: [sda] 1953525168 512-byte hardware sectors (1000205 MB)
Apr 28 20:36:55 rivendell kernel: [ 35.915344] sd 1:0:0:0: [sda] Write Protect is off
Apr 28 20:36:55 rivendell kernel: [ 35.915388] sd 1:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
Apr 28 20:36:55 rivendell kernel: [ 35.915397] sda: sda1 sda2 sda3
Apr 28 20:36:55 rivendell kernel: [ 35.940362] sd 1:0:0:0: [sda] Attached SCSI disk
Apr 28 20:36:55 rivendell kernel: [ 35.940553] sd 1:0:0:0: Attached scsi generic sg0 type 0


At the moment i'm trying to recompile the kernel with everything SATA or PATA or SCSI related as module, so i can see exactly which driver is getting used.

Anyways, any hint?

[paoletto]

to make a comparison:

Notebook sony vaio C1S (core2duo platform)
Ubuntu Gutsy
Kernel 2.6.20 self compiled



$ time cat /wind/movies/tFotR.mkv >/dev/null

real 1m41.843s
user 0m0.050s
sys 0m2.610s
$ ll /wind/movies/tFotR.mkv
-rwxrwx--- 1 root plugdev 2428746844 2008-02-17 13:23 /wind/movies/tFotR.mkv


and it means roughly 24Mb/sec

$ sudo hdparm -tT /dev/sda

/dev/sda:
Timing cached reads: 1620 MB in 2.00 seconds = 810.39 MB/sec
Timing buffered disk reads: 126 MB in 3.03 seconds = 41.54 MB/sec


(and it's a notebook hard drive!)

[Shazaam]

My WD 320gig drive has a jumper for 150 and 300mbs. Make sure your motherboard supports the faster SATA speed and check the jumper on the drive.
Here is the Western Digital support forum....
http://websupport.wdc.com/forum/

[herbster]

Have you checked your BIOS settings for tweaks on the SATA ports?

[cubeist]

My WD 320gig drive has a jumper for 150 and 300mbs. Make sure your motherboard supports the faster SATA speed and check the jumper on the drive.
Here is the Western Digital support forum....
http://websupport.wdc.com/forum/

Really? I could not find any article on WD on how to change SATA speeds via jumpers, and my WD does not have this feature. As far as I know, it is the MB that determines SATA I or II...

[paoletto]

Actually my mobo supports only SATA150, so i closed the jumper on the drive to enable SATA150 (not 300)

Also i enabled spread spectrum modulated option because i had issues without.

Actually i forgot to mention that in the beginning of January, just after i installed gutsy on the machine, performances were great!

Then i think after some gutsy update, it started to suck.
So i would exclude some drive related issue..

And, if you had a careful look at my tests, you will notice that the problem is not the speed of the drive, but the lack of DMA...

[cubeist]

Actually my mobo supports only SATA150, so i closed the jumper on the drive to enable SATA150 (not 300)

Also i enabled spread spectrum modulated option because i had issues without.

Actually i forgot to mention that in the beginning of January, just after i installed gutsy on the machine, performances were great!

Then i think after some gutsy update, it started to suck.
So i would exclude some drive related issue..

And, if you had a careful look at my tests, you will notice that the problem is not the speed of the drive, but the lack of DMA...

if you type sudo hdparm -I /dev/sda it should tell you whether dma is on or off...

Also, here is another forum post worth reading through...It may be that your speeds are actually average for a sata I drive... Remember. hdparm -tT test the maximum throughput... not average.

http://ubuntuforums.org/showthread.p...e+hardy&page=2

[cubeist]

Actually, looking back through your posts, I think your speeds are just about correct... maybe a bit slow, but I am still not sure why your cpu is being maxed out... if you run system monitor in the background and sort by cpu load, can you see which process is hogging the cpu?

[paoletto]

According with hdparm -I (but also with dmesg, which output i posted before) i have dma enabled, but the point is that when i use the disk, all the cpu goes for IO operations (wait). Which should not happen with DMA.
And of coruse i see which process is, which means cat for instance, but
it's not normal operations, but just wait. It means that cat just take few cpu % because it is getting shrinked by all the IO.

Same happens with unrar, for examples. It takes ages now because IO takes all the cpu, and it just cant do the processing.


About your opinion about SATA1, dude, honestly i think that 5Mb/s is damn slow even for my quantum fireball 1gb..

7 years ago the same cat test showed a performance of about 30mb/s on an IBM 30Gb drive connected in UDMA66.

How can be that a SATA 150 3.5" drive (it actually is a 300 but the controller is only 150) results in a throughput of 5Mb/s when even a notebook 2.5" drive beat it with a 5x performance (25Mb/s)?

Moreover, as i said before, this drive on the same machine performed very well (didnt test at that time) with a january 2008 ubuntu gutsy.

After some upgrade around february it started to suck.

Anyways, let me clarify that this "cat" test cant be like that (5Mb/s) for any modern hard drive. All drives >3gb i had performs better.

And hdparm -tT confirms it.



# hdparm -I /dev/sda

/dev/sda:

ATA device, with non-removable media
Model Number: WDC WD10EACS-00ZJB0
Serial Number: WD-WCASJ0052263
Firmware Revision: 01.01B01
Standards:
Supported: 7 6 5 4
Likely used: 8
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: 1953525168
device size with M = 1024*1024: 953869 MBytes
device size with M = 1000*1000: 1000204 MBytes (1000 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
* 64-bit World wide name
* Segmented DOWNLOAD_MICROCODE
* 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] (vendor specific)
unknown 206[13] (vendor specific)
Security:
Master password revision code = 65534
supported
not enabled
not locked
not frozen
not expired: security count
not supported: enhanced erase
260min for SECURITY ERASE UNIT.
Logical Unit WWN Device Identifier: 50014ee275f20
NAA : 5
IEEE OUI : 14ee
Unique ID : 2750f20
Checksum: correct

[cubeist]

Well if you read through the linked post, one user mentions that it depends on what you are trying to copy... 100 individual mp3's will take much longer than a 100mb file...Anyway, thats not really the point. I agree... I take back what I said in my previous post... your speeds are slow for continuous drive transfer and it should not be consuming all your IO. Unfortunately I don't know the best way to fix it... The reason I posted to your problem at all was I had an identical thing happen on a upgrade of fiesty...I tried to live with the problem, which was impossible and eventually did a clean install which fixed it.

Edit -
Just looking through your hdparm -I ... where is your transport category?!

Here is mine... fourth line down...
Transport: Serial, SATA 1.0a, SATA II Extensions, SATA Rev 2.5

I have no clue if this is related...but have not seen that omitted before.