Let's try to get SATA throughput from a disk connected to the cubietruck
- sequential read is more than 70 MB/s
- sequential write is around 35 MB/s
These throughputs are quite good, and we really can think that the cubietruck can be used like an entry level (home) NAS appliance (there's no second SATA port, so no way to to have 2 disks in RAID1 configuration...)
All the details:
SATA disk is connected to the cubietruck:
the device is a 2.5" 160GB Seagate HDD
root@cubietruck:~# hdparm -I /dev/sda
/dev/sda:
ATA device, with non-removable media
Model Number: ST9160314AS
Serial Number: 5VC29NDA
Firmware Revision: 0002SDM1
Transport: Serial
Standards:
Used: unknown (minor revision code 0x0029)
Supported: 8 7 6 5
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: 312581808
Logical/Physical Sector size: 512 bytes
device size with M = 1024*1024: 152627 MBytes
device size with M = 1000*1000: 160041 MBytes (160 GB)
cache/buffer size = 8192 KBytes
Nominal Media Rotation Rate: 5400
Capabilities:
LBA, IORDY(can be disabled)
Queue depth: 32
Standby timer values: spec'd by Standard, no device specific minimum
R/W multiple sector transfer: Max = 16 Current = 16
Advanced power management level: 128
Recommended acoustic management value: 254, current value: 0
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
* DOWNLOAD_MICROCODE
* Advanced Power Management feature set
SET_MAX security extension
* 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
* IDLE_IMMEDIATE with UNLOAD
Write-Read-Verify feature set
* WRITE_UNCORRECTABLE_EXT command
* {READ,WRITE}_DMA_EXT_GPL commands
* Segmented DOWNLOAD_MICROCODE
* Gen1 signaling speed (1.5Gb/s)
* Gen2 signaling speed (3.0Gb/s)
* Native Command Queueing (NCQ)
* Phy event counters
Device-initiated interface power management
* Software settings preservation
* SMART Command Transport (SCT) feature set
* SCT Long Sector Access (AC1)
* 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
not frozen
not expired: security count
supported: enhanced erase
48min for SECURITY ERASE UNIT. 48min for ENHANCED SECURITY ERASE UNIT.
Logical Unit WWN Device Identifier: 5000c50017db74f2
NAA : 5
IEEE OUI : 000c50
Unique ID : 017db74f2
Checksum: correct
the disk is formatted with ext4 (without any partition) and is mounted in /data
root@cubietruck:~# df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/root 15248268 2211744 12261948 16% /
devtmpfs 934496 4 934492 1% /dev
tmpfs 20480 4 20476 1% /tmp
none 186924 268 186656 1% /run
none 5120 0 5120 0% /run/lock
none 934604 0 934604 0% /run/shm
none 102400 16 102384 1% /run/user
/dev/sda 153837436 653672 145369220 1% /data
A simple write test: create a 8GB file on the filesystem
root@cubietruck:~# dd if=/dev/zero of=/data/tmp/testfile bs=1M count=8192
8192+0 records in
8192+0 records out
8589934592 bytes (8.6 GB) copied, 250.019 s, 34.4 MB/s
The reported IO throughput (sequential write) is 34.4 MB/s, which is quite good for this kind of device.
The IO activity is monitored while the file is created. Throughput is not regular
Total DISK READ: 0.00 B/s | Total DISK WRITE: 12.20 M/s
TID PRIO USER DISK READ DISK WRITE SWAPIN IO> COMMAND
1795 be/4 root 0.00 B/s 0.00 B/s 0.00 % 52.94 % [flush-8:0]
1968 be/4 root 0.00 B/s 36.87 M/s 0.00 % 47.77 % dd if=/dev/zero of=/data/tmp/testfile bs=1M count=8192
227 be/3 root 0.00 B/s 17.79 M/s 0.00 % 32.17 % [jbd2/sda-8]
1 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % init
2 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 %
...
A simple read test: the 8GB file is read
root@cubietruck:~# dd if=/data/tmp/testfile of=/dev/null bs=1M
8192+0 records in
8192+0 records out
8589934592 bytes (8.6 GB) copied, 116.468 s, 73.8 MB/s
reported read throughput is 73.8 MB/s !!!
More details from sysfs (scheduler, ...)
root@cubietruck:~# cat /sys/block/sda/queue/max_sectors_kb
512
root@cubietruck:~# cat /sys/block/sda/queue/max_hw_sectors_kb
32767
root@cubietruck:~# cat /sys/block/sda/queue/nr_requests
128
root@cubietruck:~# cat /sys/block/sda/queue/read_ahead_kb
128
root@cubietruck:~# cat /sys/block/sda/queue/rotational
1
root@cubietruck:~# cat /sys/block/sda/queue/rq_affinity
1
root@cubietruck:~# cat /sys/block/sda/queue/max_segment_size
65536
root@cubietruck:~# cat /sys/block/sda/queue/scheduler
noop deadline [cfq]
