【Performance Test】SSD (Solid State Disk) Evaluation List of 1H2009
Published Apr.22 2009,17:02 PM (GMT+8)
SSD (Solid State Disk) Evaluation List of 1H2009
Since the first release of the new solution which is based upon dynamic random access memory (DRAM) or Flash memory, solid state disk (SSD) has been winning increasing market acceptance.
It is generally known that several SSD products have featured higher power efficiency than traditional hard disks, with some already finding their feet in server and Notebook PC fields. As more and more manufactures venture into the SSD segment, what are the mainstream SSD specifications in the market? And what are the efficiency differences in SSD products?
To find answers to these questions, DRAMeXchange has evaluated several models of SSD products from different manufactures, and has combined Seagate’s traditional HDD test in the evaluation. Considering the SATA transfer specification generally adopted in SSDs, DRAMeXchange has chosen the mainboard with Intel chipset for the test platform, and the specifications are as follows:
SSD Evaluation Report
The following are results of each testing item:
Boot time of Windows system
The startup process of the operating system is an important testing item for hard disk and SSDs, for the complicated startup file reading is a good parameter of integrity reading and can reflect the direct speed experience of users.
The most generally used operating systems in ordinary PCs are Microsoft's Windows XP, Windows Vista, and Windows7 which is to be launched in the 2nd half of 2009, with Vista and Windows 7 both featuring the function of waking and reading buffer data which supports Flash storage, and both systems supporting SSD.
We installed Windows system and observed the startup file transfer speed via the PCMark 05 disk test, tracked and analyzed the startup process of PC. The core program loading time can be seen in the analysis data sheet. The Windows startup filing transfer speed is 32.4MB/s, not markable improved comparing with traditional disks, due to the intricateness of the startup process and the fragmentary in reading process.
Boot time of Linux System
We also installed Ubuntu 9.04, the latest linux distribution of Linux operating system, to test the startup speed of SSD based upon the Linux platform combining with EXT4 filing system, and to measure the reading and output capacity of SSD in Linux system. In the Bootchart test, the OCZ Vertex 120GB presented the best performance with a transfer rate of 179MB/s, followed by PQI SSD S527、Transcend 192GB which are also with a staring time within 10sec (from grub menu to the desktop).
ATTO Disk Benchmark v2.4.3
The writing and reading test was carried out on the basis of the well-known ATTO Disk Benchmark. It can be seen that the highest SSD writing rate was 169.125MB/s(PQI SSD S527 256GB), and the highest reading rate was 241.05MB/s(OCZ Vertex 120GB SSD), with a set file size of 4MB. The reading and writing rate of SSD would be slower with smaller set file size of the testing software, with the best writing rate to be 4.98MB/s (A-Data 5000 Series 64GB SSD), and the best reading rate lowered to 10.54MB/s(OCZ Vertex 120GB SSD ).
Crystal DiskMark v2.2
Crystal DiskMark is a compact testing software for testing the writing and reading rate of large- and small-size files. In the continuous reading and writing performance test which utilized it as the chief testing tool, PQI SSD S527 256GB exhibited the fastest writing rate of 167.4MB/s as well as the fastest reading rate of 235.3MB/s. When the file size was switched to 512KB, most of the SSDs slowed down just slightly in reading, while the writing rate average dropped by nearly 50 percent. In tests with small-size file, the situation was similar to the former ATTO test.
X-bit labs FC-Test
This item is to test the operating efficiency of the disks under different applications, with fewer seconds in the result representing the better performance.
In the Windows pattern item under common user environment, the top three in speed are OCZ Vertex 128GB、A-Data S592、Corsair 128GB respectively.
This test clearly shows the efficiency performances of SSDs of varying specifications under different application occasions, with the definite model information and model numbers listed in the results. In the overall performance test, the top three with highest continuous writing and reading rate are OCZ、A-Date S592、Corsair 128GB respectively.
To be noted in the HDTach test is the access time which is merely between 0.1ms~0.2ms, which is also the strong suit of SSD comparing with traditional hard disks, making it more preferable in index and fast search. And the Burst Speed test reflects the maximum output of SSD under maximum interface frequency width. As some SSDs feature Cache, the bigger storage capacity ensures the higher score in this test.
HDTune Pro v3.50
In the HDTune Pro test, we evaluated the objects by average reading. This testing software is commonly seen. It can be shown in the diagram that SSDs featuring Cache and better design surpass the others.
The significant part of this test is to measure the highest input/output performance of SSDs under big volume of IO which reflects the design level of the SSD controllers. Corsair 128GB took the lead in this test, with A-Data 64Gb and A-Data S592 128GB、OCZ Vertex 120GB following behind.
Though A-Data 64GB is lagging behind in writing and reading efficiency, in this test it performed pretty well, suggesting Flash chip of poor writing and reading efficiency may have been adopted while the controller was no bad. It is the OEM product of Samsung of Korea.
The SSD products exhibited really impressive performance in writing and reading efficiency in the PCMARK 05 test. Unlike the hard disks which require motor running and the reading head to move, the SSD products require a searching time near 0, which ensures the improvement in input/output per second (IOPS), and sequentially in the random reading efficiency reflected in the performance of SSD products. As the HDD score in PCMark05 test is a overall measurement, it can be concluded that the products with best overall performances are A-Data S592 and OCZ Vertex which matches each other, and the following PQI SSD S527 also performs well and features high storage capacity, while the higher temperature than other SSD products is to be noted.
The SSDs based on Flash memory features lower power consumption than the counterparts based on DRAM. The power consumption of SSDs are mostly between 0.5W and 3W, not much lower than regular hard disks. Though the power efficiency of SSD is higher than traditional hard disks, the standby and energy saving methods are not as mature, and there is not complete supportive power-saving pattern.
The greatest advantage of SSD is the elimination of the machinery structure like motor and dish, reducing the heat generated. Because SSDs give off less heat, fans are not needed any more, which makes the application occasions of DT or NB more quiet and avoids the over-heat in the disk positioning area. The elimination of fans also reduce the noise in the application occasions of SSDs, beneficial for both the environment and the product itself.
Overall Evaluation of SSD
As the writing times of Flash memory chips is limited to between thousand of times to ten thousand times, many man be concerned about the lifespan of Flash memory based SSDs. Considering this fact, the manufacturers have adopted the algorithm which takes account of the storage times and detrition of different areas of the chip, and have established the balanced quality subject to the written data, avoiding the over-written of specific zone of the chip. The mostly used technology is called Wear Leveling.
The key component of SSD is controller which accounts for “Wear Leveling” . It can be seen in all the tests that the major difference among the SSD products is in the writing and reading efficiency. Firstly, the efficiency of different Flash chips adopted, though all are MLC NAND Flash, can influence the overall SSD efficiency. Secondly, the controlling chip adopted and the size of Cache also could have impact on the SSD efficiency. For example, with its 64M Cache, the OCZ 120GB has got higher scores in several tests than other SSD products.
We also found that many products provide mini USB as well as the SATA interface, which are suitable for use in business-use Notebook PCs and desk PCs, but are still not high-end SSDs. Except that high-end SSDs mainly use SLC chips, the SSD products with PCI-E interface are more efficient than regular SSDs with SATA interface, and they are not designed for common use but for use in workstations and severs.
As to stability, we have found efficiency of some SSDs dropped in the processes of tests and recovered after disk formatting. SSD efficiency has not remarkably dropped in the large volume and long time writing and reading test, which part we will continue tracking in future reports.
Considering the price, take 128GB SSD as an example and it costs USD300 ~USD 400 which is not attractive to end users. In the long term, DRAMeXchange believes that SSD is going to gain more market share after 2010 ,once the price goes soft.
In this 1H2009 SSD evaluation list, we have offered different awards and honors to some products based on their scores in the tests.
A. Best Overall performance >> OCZ Vertex 120GB
B. Best transfer rate >>PQI SSD S527 256GB
C. Best access time >> A-Data S592 128GB SSD
D. Best IO Efficiency>>Corsair CMFSSD-128GB
E. Best system disk >>Transcend TS192GSSD25S-M 192GB
F. Best multi-interface design>>KingSpec KSD-SU25.1-064MJ
G. Best entry SSD >>Apacer 64GB SSD
H. Best industrial design>>Chaintech APOGEE FlashSSD 128GB
I. Best cooling design>>Patriot Memory 128GB SSD
Test data and specifications: