On Tue, 3 Mar 2009, Craig Falconer wrote:
John Carter wrote, On 02/03/09 17:19:
On Mon, 2 Mar 2009, Craig Falconer wrote:
time dd if=/dev/zero of=/file.dd bs=16k count=16k
onto sda (4GB) that took 11.34 seconds (27.9 MB/sec)
However onto sdb it took 55.93 seconds (4.8 MB/sec)
time dd if=/dev/zero of=/file.dd bs=8k count=64k
sda 39.2 sec 13.7 MB/sec
sdb 77.2 sec 6.9 MB/sec
Again you're probably testing the speed of ram, not flash.
Can you replicate my results? Using whatever tests you like.
Sigh! Since I can think of several places where a gut feel for these
numbers will help me in the work context, eg. I'm in the process of
spec'ing a server for a build system... it will help me to get a grip
on the current realitys of shifting data around.
Ah yes, another "gotcha" with benchmarking on Intel ATOM based
EEEp's. Powersave mode! Toggling between powersave mode and high
performance changes the clock speed of the CPU!
(Weird. With the current kernel I have in there that doesn't seem to
be happening. I'm sure I saw the Mhz change in /proc/cpuinfo once.)
ie. All benchmarks are conditional on what mode you're in.
I did mention this was a _very_ black art didn't I?
Exec summary:
A Western Digital magnetic 80Gb hard drive on a desktop is running at
around 54MB/s on read and 39MB/s on write.
A USB pen drive runs at about 14mb/s on read, 4.7 on write.
An EEE 901 root disk runs at 31MB/s on read and an 13mb/sec on write.
An EEE 901 home disk runs at 36MB/s on read and an 6mb/sec on write.
ie. All things are slower on write than read, flash is nearly 3 times
slower on write than read.
Powersave vs Super made no difference, but I have reason to believe
that the control is not working. ie. I have no idea whether the tests
were done in powersave or super mode.
All tests were done on ext3 filesystems.
For comparison I have tossed in desktop performance and usb pen.
Desktop Western Digital WD800JD 80Gb, hdparm -t reports 54Mb/s, dd
reports about 42MB/s, with sync about 39Mb/s.
Second drive identical, possibly because it's busy reports around 30
MB/s on dd
USB pen on destop 1gb Imation. hdparm -t reports 14Mb/s, dd reports
5mb/s, with sync around 4.7 MB/s
EEE PC 901 in powersave? mode
4gb sda root partition hdparm -t reports around 31MB/s, dd reports
around 15mb/s, dd with sync around 13 MB/s
16Gb sdb /home partion hdparm -t reports around 36Mb/s, dd reports
around 8.5MB/s, dd with sync around 6MB/s
John Carter Phone : (64)(3) 358 6639
Tait Electronics Fax : (64)(3) 359 4632
PO Box 1645 Christchurch Email : john.car...@tait.co.nz
New Zealand
Timing for desktop PC... (PC busy, running measurements at nice --10
with background stuff running at nice -19, therefore measurements
slightly flaky)
processor : 0
vendor_id : GenuineIntel
cpu family : 15
model : 6
model name : Intel(R) Pentium(R) D CPU 3.40GHz
stepping : 4
cpu MHz : 3400.000
cache size : 2048 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 6
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc
pebs bts pni monitor ds_cpl est cid cx16 xtpr lahf_lm
bogomips : 6805.95
clflush size : 64
processor : 1
vendor_id : GenuineIntel
cpu family : 15
model : 6
model name : Intel(R) Pentium(R) D CPU 3.40GHz
stepping : 4
cpu MHz : 3400.000
cache size : 2048 KB
physical id : 0
siblings : 2
core id : 1
cpu cores : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 6
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc
pebs bts pni monitor ds_cpl est cid cx16 xtpr lahf_lm
bogomips : 6800.11
clflush size : 64
/dev/sda:
ATA device, with non-removable media
Model Number: WDC WD800JD-00LSA0
Serial Number: WD-WMAM9S809258
Firmware Revision: 06.01D06
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: 156301488
LBA48 user addressable sectors: 156301488
device size with M = 1024*1024: 76319 MBytes
device size with M = 1000*1000: 80026 MBytes (80 GB)
Capabilities:
LBA, IORDY(can be disabled)
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
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)
* SATA-II signaling speed (3.0Gb/s)
* Host-initiated interface power management
* Phy event counters
* 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)
Security:
Master password revision code = 65534
supported
not enabled
not locked
frozen
not expired: security count
not supported: enhanced erase
Checksum: correct
/dev/sda:
Timing buffered disk reads: 168 MB in 3.00 seconds = 55.96 MB/sec
/dev/sda:
Timing buffered disk reads: 164 MB in 3.04 seconds = 53.99 MB/sec
/dev/sda:
Timing buffered disk reads: 164 MB in 3.04 seconds = 53.97 MB/sec
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 11.2854 s, 47.6 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.05
System time (seconds): 2.13
Percent of CPU this job got: 15%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:14.14
Major (requiring I/O) page faults: 1
Minor (reclaiming a frame) page faults: 891
Voluntary context switches: 3052
Involuntary context switches: 155
Swaps: 0
File system inputs: 128
File system outputs: 1048600
Page size (bytes): 4096
Exit status: 0
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 12.9438 s, 41.5 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.04
System time (seconds): 2.06
Percent of CPU this job got: 14%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:14.74
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 888
Voluntary context switches: 1659
Involuntary context switches: 123
Swaps: 0
File system inputs: 128
File system outputs: 1048592
Page size (bytes): 4096
Exit status: 0
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 11.0121 s, 48.8 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.06
System time (seconds): 2.16
Percent of CPU this job got: 16%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:13.77
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 891
Voluntary context switches: 2007
Involuntary context switches: 174
Swaps: 0
File system inputs: 40
File system outputs: 1048608
Page size (bytes): 4096
Exit status: 0
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 12.5034 s, 42.9 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.03
System time (seconds): 2.14
Percent of CPU this job got: 15%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:14.42
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 889
Voluntary context switches: 10352
Involuntary context switches: 148
Swaps: 0
File system inputs: 96
File system outputs: 1048584
Page size (bytes): 4096
Exit status: 0
======================================================================
/dev/sdb:
ATA device, with non-removable media
Model Number: WDC WD800JD-00MSA1
Serial Number: WD-WMAM9AS18929
Firmware Revision: 10.01E01
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: 156301488
LBA48 user addressable sectors: 156301488
device size with M = 1024*1024: 76319 MBytes
device size with M = 1000*1000: 80026 MBytes (80 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
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)
* SATA-II signaling speed (3.0Gb/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)
Security:
Master password revision code = 65534
supported
not enabled
not locked
frozen
not expired: security count
not supported: enhanced erase
Checksum: correct
/dev/sdb:
Timing buffered disk reads: 168 MB in 3.01 seconds = 55.73 MB/sec
/dev/sdb:
Timing buffered disk reads: 136 MB in 3.08 seconds = 44.15 MB/sec
/dev/sdb:
Timing buffered disk reads: 156 MB in 3.08 seconds = 50.69 MB/sec
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 17.7147 s, 30.3 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/extra_drive/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.02
System time (seconds): 2.11
Percent of CPU this job got: 11%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:19.27
Major (requiring I/O) page faults: 1
Minor (reclaiming a frame) page faults: 888
Voluntary context switches: 391
Involuntary context switches: 87
Swaps: 0
File system inputs: 560
File system outputs: 1048592
Page size (bytes): 4096
Exit status: 0
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 18.1168 s, 29.6 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/extra_drive/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.03
System time (seconds): 2.27
Percent of CPU this job got: 11%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:20.70
Major (requiring I/O) page faults: 1
Minor (reclaiming a frame) page faults: 890
Voluntary context switches: 170
Involuntary context switches: 150
Swaps: 0
File system inputs: 320
File system outputs: 1048592
Page size (bytes): 4096
Exit status: 0
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 17.7574 s, 30.2 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/extra_drive/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.03
System time (seconds): 2.35
Percent of CPU this job got: 11%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:20.90
Major (requiring I/O) page faults: 1
Minor (reclaiming a frame) page faults: 887
Voluntary context switches: 3977
Involuntary context switches: 157
Swaps: 0
File system inputs: 184
File system outputs: 1048592
Page size (bytes): 4096
Exit status: 0
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 16.9958 s, 31.6 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/extra_drive/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.04
System time (seconds): 2.24
Percent of CPU this job got: 11%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:20.72
Major (requiring I/O) page faults: 1
Minor (reclaiming a frame) page faults: 888
Voluntary context switches: 939
Involuntary context switches: 118
Swaps: 0
File system inputs: 304
File system outputs: 1048600
Page size (bytes): 4096
Exit status: 0
======================================================================
Imation 1Gb USB pen
/dev/sdc:
/dev/sdc:
Timing buffered disk reads: 44 MB in 3.05 seconds = 14.41 MB/sec
/dev/sdc:
Timing buffered disk reads: 44 MB in 3.10 seconds = 14.18 MB/sec
/dev/sdc:
Timing buffered disk reads: 42 MB in 3.04 seconds = 13.82 MB/sec
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 102.692 s, 5.2 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/jpen/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.02
System time (seconds): 2.07
Percent of CPU this job got: 1%
Elapsed (wall clock) time (h:mm:ss or m:ss): 1:54.53
Major (requiring I/O) page faults: 1
Minor (reclaiming a frame) page faults: 893
Voluntary context switches: 1129
Involuntary context switches: 16
Swaps: 0
File system inputs: 1161
File system outputs: 1050712
Page size (bytes): 4096
Exit status: 0
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 101.562 s, 5.3 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/jpen/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.04
System time (seconds): 2.16
Percent of CPU this job got: 1%
Elapsed (wall clock) time (h:mm:ss or m:ss): 1:53.91
Major (requiring I/O) page faults: 3
Minor (reclaiming a frame) page faults: 892
Voluntary context switches: 1649
Involuntary context switches: 32
Swaps: 0
File system inputs: 1792
File system outputs: 1052728
Page size (bytes): 4096
Exit status: 0
======================================================================
EEE PC 901 In powersave mode!
/dev/sda:
ATA device, with non-removable media
Model Number: ASUS-PHISON SSD
Serial Number: SOQ2882269
Firmware Revision: TST2.04U
Standards:
Supported: 5 4
Likely used: 6
Configuration:
Logical max current
cylinders 7818 7818
heads 16 16
sectors/track 63 63
--
CHS current addressable sectors: 7880544
LBA user addressable sectors: 7880544
device size with M = 1024*1024: 3847 MBytes
device size with M = 1000*1000: 4034 MBytes (4 GB)
Capabilities:
LBA, IORDY(cannot be disabled)
Standby timer values: spec'd by Standard, no device specific minimum
R/W multiple sector transfer: Max = 1 Current = 0
DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 *udma4
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:
* Power Management feature set
* WRITE_BUFFER command
* READ_BUFFER command
* NOP cmd
* CFA feature set
* Mandatory FLUSH_CACHE
Integrity word not set (found 0x0000, expected 0x9da5)
/dev/sda:
Timing buffered disk reads: 94 MB in 3.01 seconds = 31.28 MB/sec
/dev/sda:
Timing buffered disk reads: 94 MB in 3.01 seconds = 31.24 MB/sec
/dev/sda:
Timing buffered disk reads: 94 MB in 3.01 seconds = 31.26 MB/sec
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 36.4936 s, 14.7 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.14
System time (seconds): 7.22
Percent of CPU this job got: 18%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:40.38
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 906
Voluntary context switches: 603
Involuntary context switches: 200
Swaps: 0
File system inputs: 88
File system outputs: 1048584
Page size (bytes): 4096
Exit status: 0
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 32.3764 s, 16.6 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.16
System time (seconds): 8.04
Percent of CPU this job got: 20%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:39.25
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 906
Voluntary context switches: 648
Involuntary context switches: 207
Swaps: 0
File system inputs: 24
File system outputs: 1048584
Page size (bytes): 4096
Exit status: 0
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 35.4887 s, 15.1 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.12
System time (seconds): 7.39
Percent of CPU this job got: 18%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:39.57
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 908
Voluntary context switches: 890
Involuntary context switches: 198
Swaps: 0
File system inputs: 0
File system outputs: 1048584
Page size (bytes): 4096
Exit status: 0
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 34.3948 s, 15.6 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.14
System time (seconds): 7.80
Percent of CPU this job got: 19%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:40.78
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 906
Voluntary context switches: 870
Involuntary context switches: 190
Swaps: 0
File system inputs: 0
File system outputs: 1048584
Page size (bytes): 4096
Exit status: 0
======================================================================
EEE PC 901 in powersave mode second drive...
/dev/sdb:
ATA device, with non-removable media
Model Number: ASUS-PHISON SSD
Serial Number: SOQ2882288
Firmware Revision: TST2.04U
Standards:
Supported: 5 4
Likely used: 6
Configuration:
Logical max current
cylinders 16383 16383
heads 16 16
sectors/track 63 63
--
CHS current addressable sectors: 31522176
LBA user addressable sectors: 31522176
device size with M = 1024*1024: 15391 MBytes
device size with M = 1000*1000: 16139 MBytes (16 GB)
Capabilities:
LBA, IORDY(cannot be disabled)
Standby timer values: spec'd by Standard, no device specific minimum
R/W multiple sector transfer: Max = 1 Current = 0
DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 *udma4
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:
* Power Management feature set
* WRITE_BUFFER command
* READ_BUFFER command
* NOP cmd
* CFA feature set
* Mandatory FLUSH_CACHE
Integrity word not set (found 0x0000, expected 0x9ba5)
/dev/sdb:
Timing buffered disk reads: 110 MB in 3.04 seconds = 36.13 MB/sec
/dev/sdb:
Timing buffered disk reads: 110 MB in 3.05 seconds = 36.09 MB/sec
/dev/sdb:
Timing buffered disk reads: 110 MB in 3.04 seconds = 36.13 MB/sec
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 80.0692 s, 6.7 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/home/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.14
System time (seconds): 7.69
Percent of CPU this job got: 8%
Elapsed (wall clock) time (h:mm:ss or m:ss): 1:28.35
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 905
Voluntary context switches: 615
Involuntary context switches: 220
Swaps: 0
File system inputs: 48
File system outputs: 1048584
Page size (bytes): 4096
Exit status: 0
65536+0 records in
65536+0 records out
536870912 bytes (537 MB) copied, 63.1645 s, 8.5 MB/s
Command being timed: "bash -c dd if=/dev/zero of=/home/file.dd bs=8k
count=64k;sync"
User time (seconds): 0.10
System time (seconds): 8.36
Percent of CPU this job got: 9%
Elapsed (wall clock) time (h:mm:ss or m:ss): 1:27.72
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 906
Voluntary context switches: 976
Involuntary context switches: 219
Swaps: 0
File system inputs: 32
File system outputs: 1048584
Page size (bytes): 4096
Exit status: 0
