by Dmitry Vasiliev
09/08/2011 | 11:43 AM
It's no secret that the performance of a computer’s disk subsystem is quite an important factor when it comes to comfortable user experience. Of course, it cannot add more computing power to your CPU or increase the frame rate in your favorite game (if you've got enough of system memory), but having your OS or heavy applications like Adobe Photoshop load much faster is a very nice thing. A computer’s higher overall responsiveness is what we mean by comfortable user experience here.
The most straightforward way to make your disk subsystem faster is to buy a solid state drive large enough to store your OS and applications. However, this method is way too expensive for many users. It also involves the trouble of reinstalling your OS and applications on the SSD or moving them there from your hard disk.
A modern SSD with a capacity of 100 to 120 gigabytes and based on the cheaper MLC flash memory type can be bought for $200-270, which is about $50-100 more than the price of a 3-terabyte hard disk drive. This storage capacity will only be enough for installing an OS together with a standard selection of tools you use every day plus a few heavy professional applications. Everything beyond that limit will have to be stored on a traditional and slow HDD or you have to spend even more money to buy a larger SSD.
That said, the specific applications the user works with over a short period of time (a week, for example) is often rather limited. One week you're editing your summer vacation photos in Photoshop, playing a latest 3D shooter or browsing the Web, but the next week you're doing your work in Microsoft Office. So, some files would take place on your expensive SSD without you really needing them at the moment.
Is there a way to increase the efficiency of your fast SSD storage? Yes, of course. The solution is in storing all data on a conventional, cheap but high-capacity HDD and using a low-capacity not-very-expensive SSD as a cache for the files and applications you're frequently accessing right now.
This concept of a hybrid disk subsystem can be implemented with the Smart Response technology supported by the Intel Z68 chipset or with a special disk controller like HighPoint RocketHybrid 1220. Both suggest that you use a small-capacity SSD as a cache for a large-capacity HDD. There are no viable single-drive hybrid solutions as yet, i.e. an HDD with a large internal flash memory cache, so you have to use two drives instead of one.
We discussed Intel's Smart Response technology in our earlier reviews, so we won't dwell on it here. Let's take a look at the hybrid controller from HighPoint instead.
The HighPoint RocketHybrid 122x series consists of two controllers designed for a PCI Express 2.0 x1 slot. These are the RocketHybrid 1220 with two SATA 6 Gb/s ports and the RocketHybrid 1222 which has external (eSATA) rather than internal ports.
The controllers are based on a Marvell 88SE9130 chip which was announced at CES 2011. In fact, even the web-interface and monitoring utility are branded by Marvell rather than HighPoint.
The HighPoint RocketHybrid 1220 is otherwise identical to the HighPoint Rocket 620 (which was shipped with 3-terabyte Western Digital drives, for example) except that the latter was based on a Marvell 88SE9125 chip that provided standard RAID capabilities without the option of building a hybrid disk subsystem.
The accessories to the controller include a disc with drivers and user manual, a brief paper manual, a couple of SATA cables and two mounting brackets (a standard and a low-profile one).
The manufacturer claims an ideal price/performance ratio for a hybrid disk subsystem built on a RocketHybrid 122x controller: 80% of the SSD performance and the huge storage capacity of the HDD. This is in fact what Marvell promised when announcing their 88SE9130 chip.
The RocketHybrid 1220 allows to set the virtual hybrid drive HyperDuo at either of two modes: Safe or Capacity.
In the Safe mode the hot, i.e. frequently accessed, files exist in two copies on the HDD and SSD. In the Capacity mode the hot files are stored on the SSD, so the user can utilize the entire capacity of both disks. The manufacturer claims that the Capacity mode is also somewhat faster (at the expense of reliability because there is a risk of data loss in case of a failure while a file is being transferred between the HDD and SSD).
The Safe mode can be enabled by simply connecting an HDD with an installed OS to one of the controller’s ports and a new SSD, to another. Then you just have to do some setting up in the controller’s BIOS. Creating a hybrid drive in the Capacity mode is not any more difficult in terms of setting up but requires that you reinstall the OS.
The RocketHybrid 1220 allows the user to choose the folders to cache in the SSD rather than leave that up to the controller as with Intel Smart Response technology. You can do this by checking the Auto and Cache checkboxes next to folders. You can’t combine the two options, of course. When you choose one, the other is disabled.
By default, the RocketHybrid 122x controllers cache data automatically but you can manually enable caching of certain folders or prohibit to cache some of them (by unchecking both checkboxes).
Our testbed was configured as follows:
We use the latest drivers from the manufacturers of our testbed components.
It is the disk subsystem’s speed of reading that determines how responsive a computer is, so we are going to test the speed of loading the OS and various applications, omitting the speed of writing and the performance of those applications.
We will run each test five times with each disk subsystem configuration (an HDD, an SSD and hybrid disks built with Intel Smart Response technology or the HighPoint RocketHybrid 1220 controller working in different modes).
This will help us see the results of Windows 7’s optimizations (Prefetcher and SuperFetch) with the single SSD and HDD and check out how files caching depends on the number of application runs with the hybrid disk (HDD+SDD).
We will benchmark the speed of loading of the following applications:
With the 2D applications the loading time is counted from launching the application (from the OS loading screen for Windows 7) to the loading of the application’s main window (Desktop for Windows) with all of its interface elements.
With the 3D applications we measure the speed of loading a scene from starting the application up to the appearance of the game scene on the screen (with S.T.A.L.K.E.R.: Call of Pripyat we turn our stopwatch on right after the system configuration analysis screen).
We round off our measurements to seconds (towards the closest integer).
The following disk subsystem configurations will be tested:
First let’s see the results of the five runs of each test with each disk subsystem configuration. For better readability, the diagrams are split up into three parts according to the load time and application type.
The first diagram for each configuration shows the speed of loading the OS and the 3D game scenes. They take the longest time to load.
The second diagram is about Futuremark’s benchmarks.
The third diagram contains the rest of the test applications, namely Microsoft Office 2007 and Adobe Photoshop CS 5.1.
We’ll start out by establishing the reference point with the single HDD and the single SSD. Then we will check out the hybrid subsystems based on Intel Smart Response technology and on the HighPoint RocketHybrid 1220 controller.
This is the slowest disk subsystem among the configurations we are going to test, yet it is not hopelessly slow. Thanks to Prefetcher and SuperFetch technologies the loading time of many applications improves after the OS is rebooted. These Windows 7 features would be even more effective if our testbed had more system memory.
Although the conventional HDD improves the loading time of the OS and applications on their subsequent runs, it cannot match the SSD. The HDD’s best results are worse than the SSD’s worst ones.
We can also note that the SSD makes use of Prefetcher and SuperFetch although the effect of these technologies is not as conspicuous as with the HDD.
Our first Smart Response configuration has the smallest cache size possible, only 18.6 gigabytes out of the SSD’s full capacity of 80 gigabytes. The remaining capacity might be used to install important applications, leaving the less important ones and the OS for Smart Response to accelerate.
We can see that the loading times improve greatly on the subsequent runs compared to the first run which is slow and comparable to the speed of loading from a conventional HDD.
On the other hand, the hybrid subsystem (in any configuration, as you will see shortly) cannot match the SSD in terms of loading the OS. The SSD is about twice as fast as the hybrid drive even after a few restarts.
This disk subsystem configuration will help us see if there is any difference in the performance of the hybrid drive depending on the size of the SSD cache.
This configuration leaves a smaller area of the SSD free from caching compared to the previous configuration. So, the latter is going to be preferable if it has a similar performance.
Indeed, you can see that this and previous configurations are roughly similar in performance (at least, under the conditions of our test session), so you can save some money by using a smaller SSD cache.
If the size of the SSD cache is not a critical factor (at least, under our conditions), we want to see the effect of the SSD's speed on the performance of the hybrid solution. So, we take a Smart Response-optimized Larson Creek disk with a capacity of only 20 gigabytes. It is based on SLC as opposed to MLC flash memory employed in the 80-gigabyte 320 series disk you've seen in the previous tests.
Besides, we enable the Maximized mode here (it hardly differs from the basic Enhanced mode in terms of reading, and it is the read seed that’s the crucial factor for loading applications).
So, the speed of the caching SSD proves to be more important than its storage capacity in many of our tests. The difference in performance from the slower MLC-based SSD is not large, yet notable. On the other hand, the configuration with the small-capacity and fast SSD falls behind in some applications.
The HighPoint RocketHybrid 1220 controller is first tested with the simplest configuration possible: the Safe mode saves you the trouble of reinstalling your OS. The controller itself chooses what files to cache.
The RocketHybrid 1220’s Safe mode is similar to Smart Response’s Enhanced mode ("hot" data are copied to both the HDD and the SSD), the single difference being the lack of limitations on the size of the caching SSD.
The difference in performance between the two hybrid technologies is not large, either. The HighPoint controller (in this as well as the other two configurations) loads applications faster than the Smart Response configurations on the first run. This must be due to the fact that some data are originally copied from the HDD to the caching SSD: it takes quite a long time to build a HyperDuo drive.
But when we launch our applications for a second, third, etc. time, the Smart Response configurations prove to be generally faster.
Now let's check the HighPoint controller out in the Capacity mode which allows you to make full use of the storage capacity of both the SSD and the HDD. Although the few dozen gigabytes of SSD storage look negligible compared to the terabytes of storage available with today's HDDs, you can still find a good use for them.
The manufacturer claims that the Capacity mode improves performance. Indeed, our tests indicate a certain increase in the speed of loading of our applications. This mode is going to be even more effective at writing since the controller won’t have to copy data in parallel to the slow HDD.
The performance benefits of the Capacity mode are nice to have, but can we improve them by manually selecting the folders we want to be cached?
We checked this out by moving the folders of our test applications and all of the movable Windows folders to the SSD.
As you can see in the diagram, this helped us increase the resulting performance a little, although not without some odd results that we will discuss later on.
Now let’s compare all of our disk configurations in specific applications. We compare the average results based on five runs of each application.
The two extremes of the performance range might have been expected: the single SSD is the fastest to boot the OS up whereas the conventional HDD is the slowest of all.
The hybrid configurations do not perform much faster compared to the HDD (their results almost coincide after a few runs of the test), but this can be easily explained. Many protected system files from the Windows installation on the hard disk could not be cached to the SSD and had to be read from the HDD, slowing the boot-up process down.
As for the specific results, we can see that the Smart Response configurations with 64GB cache and the Larson Creek configuration are slower than the rest of the hybrid subsystems. The former take a lot of time for the first run of the test when data is not yet cached to the SSD whereas the latter configuration also has a rather slow speed during the second and subsequent runs of the test.
The leading position of the HighPoint controller in Capacity mode with selective caching is not really unquestionable. This configuration is superior due to its fast first run of the test, but falls behind the Smart Response configuration with 64GB cache on the subsequent runs.
All in all, booting the OS up is not a strong point of the hybrid configurations. After a few reboots of the computer, the performance of the conventional HDD is almost as high as that of the hybrid subsystems.
This application is more appropriate for hybrid disk subsystems than the OS, so we can see the performance benefits clearly.
The first run of the application is always faster on the HighPoint configurations than on the Smart Response ones. The latter take about as much time for that as the conventional HDD whereas the HighPoint-based disk subsystems spend about as much time to run Photoshop for the first time as for the subsequent runs. We expected that for the selective caching configuration but the high performance of the HighPoint controller in automatic caching mode is quite a surprise.
Another surprise is that the HighPoint with selective caching is somewhat faster than the pure SSD connected to the Intel chipset’s controller. This must be due to some measurement inaccuracies or differences in the performance of the Intel and Marvell SATA-controllers.
We must acknowledge that, apart from the HighPoint controller with selective caching, the Smart Response configurations load Photoshop faster on the subsequent runs than the HighPoint ones.
The popular text editing application proves the viability of the hybrid disk concept. The slowest of our hybrid configurations is more than three times as fast as the conventional HDD basing on the average of five runs of the test.
Like in the previous test, the HighPoint with selective caching in Capacity mode is a little bit faster than the pure SSD connected to Intel's chipset controller. It may be due to measurement inaccuracies, though.
The HighPoint controller enjoys a bigger advantage over Smart Response in this test in terms of average scores. The slowest RocketHybrid 1220-based configuration equals the fastest Smart Response one. However, like in the previous test, this is largely due to Word 2007 taking longer to load on the first run with the Smart Response configurations.
We can note that Microsoft Office applications are loaded almost instantaneously once they are in the SSD cache. The order of our tests was as follows: Word, Excel, PowerPoint. Clearly, the shared dynamic libraries loaded with Word 2007 helped load Excel and PowerPoint faster.
Of course, if you load a heavy application in between Word and Excel, the shared Microsoft Office libraries will be unloaded from the cache and the next application will take longer to load. Still, it is a more probable scenario that a user works in office applications without alternating them with something like 3D games.
The benefits of the pure SSD and the hybrid configurations are obvious but you should keep it in mind that their advantage is more impressive in the diagrams than in real life. The difference between 1 and 3 seconds to load an application is not really crucial for real-life scenarios.
Everything we’ve said above about Excel applies to PowerPoint, too. We can only note that the SSD and hybrid subsystems get even faster whereas the HDD, somewhat slower than in the previous test.
The SSD and the hybrid disk subsystem prove their superiority over the conventional HDD once again. The HighPoint-based configuration with automatic caching in Capacity mode fails for unknown reasons (the other two HighPoint-based configurations are twice as fast), yet it is almost twice faster than the conventional HDD.
The rest of the hybrid configurations are about four times as fast as the HDD, the Intel 320 series SSD turning out to be slower not only than the HighPoint in two configurations but also than the Smart Response configuration with a Larson Creek SSD.
We can also note that the application takes almost the same time to load on the HighPoint controller irrespective of whether it’s a first run or not. The Smart Response configurations are overall faster when launching the application for a second, third, etc. time.
As opposed to the gaming tests (see below) we measure the time it takes to load the main 3DMark 06 window here. Still, we can see that the hybrid disk configurations are twice as fast as the HDD, the pure SSD being almost three times as fast as the HDD.
This test shows that Smart Response technology is good not only for the subsequent runs of the application but also on average. The hybrid subsystems are all inferior to the pure SSD but the Smart Response configurations are obviously ahead of the HighPoint-based ones despite taking somewhat longer to load the application for the first time.
By the way, while the results of the Smart Response configurations are predictable (the configuration with the faster SSD is ahead; the configuration with the slower SSD and the minimum cache size is the slowest), the HighPoint-based setups do not perform as expected. The seemingly fastest configuration (Capacity mode with selective caching) turns out to be the slowest whereas the Safe mode with automatic caching is for some reason the most effective here.
This application is loaded much faster than the older 3DMark version discussed above. The effect from using an SSD instead of an HDD is conspicuous but smaller.
As opposed to 3DMark, we don’t see anything odd about the results. As in many other tests we’ve seen, the HighPoint configurations have a better average result thanks to loading the application faster on the first run but the subsequent runs negate this advantage.
The Smart Response configuration with the fast Larson Creek SSD is slower than the other configurations based on Smart Response technology which may be due to its smaller cache size.
You can see the game settings in the screenshot.
The SSD and hybrid disk configurations do not have a crucial advantage with this type of applications. Anyway, we can note that the HighPoint-based configurations are ahead of the Smart Response ones, and not only due to their faster first run.
The HighPoint-based subsystem with selective caching is ahead of the pure SSD connected to the chipset controller. This indicates that the Marvell chip can be faster than the Intel Z68 chipset in some scenarios.
You can see the game settings in the screenshot.
The SSD and hybrid disks do not improve the loading time of this game, either. On the other hand, we can note that the hybrid subsystems (except for the HighPoint controller in Safe mode and the Smart Response configuration with the Larson Creek SSD) are but slightly slower than the pure SSD.
You can see the game settings in the screenshot.
As opposed to the previous two games, the effect from using a pure SSD or a hybrid disk subsystem is conspicuous in Crysis.
The pure SSD is of course the fastest, being almost four times as fast as the conventional HDD.
The three Smart Response configurations go neck and neck here. They have the same results in each run of the test and they are all about three times as fast as the conventional HDD.
The HighPoint controller produces rather odd results in the Capacity mode. It is the closest to the pure SSD with automatic caching but slows down with selective caching. The loading time even increased with each subsequent run after we enabled selective caching!
These oddities cannot be written off as some problems with drivers or anything because the selective caching configuration was tested right after the automatic caching one which had been free from that problem. The OS and drivers were the same, so the only difference was that we had cached all test data to the SSD before the test.
Interestingly, the fast loading of data from the SSD or hybrid configurations affected the overall speed of the game with Crysis whenever our testbed lacked system memory (the memory amount installed in our testbed is not enough for a heavy 3D game). With the HDD, the game's frame rate was about 15 fps whereas the SSD and hybrid configurations increased it to about 50 fps. Well, system memory doesn't cost much today, so installing an extra 4 gigabytes of system RAM is going to be cheaper than buying a cheap single-platter HDD, let alone an SSD.
You can see the game settings in the screenshot.
The last 3D game that we used for our tests loads the scene faster with the SSD or hybrid disk configurations. The difference between the pure SSD and hybrid disks is small but larger than in Call of Pripyat.
The HighPoint-based configurations are faster on average but, like in many previous tests, this is largely due to their faster first run of the test.
Our tests show that Intel Smart Response technology delivers impressive results. Moreover, the performance of our hybrid disk subsystems didn't depend on the capacity of the caching SSD under the conditions of our tests. This may be the reason why Intel focused on speed rather than capacity in their Smart Response-optimized Larson Creek SSD (but we don’t understand why they didn’t use SATA 6 Gb/s which brings about considerable benefits for SSDs compared to SATA 3 Gb/s).
Of course, a larger caching SSD is going to provide certain advantages if your frequently used applications and data are larger than the cache size. However, this scenario seems rather unlikely for the majority of users, so we guess that purchasing a 40GB SSD would be the optimal solution.
The HighPoint RocketHybrid 1220 controller supports SATA 6 Gb/s and hybrid drives, just like the Intel Z68 chipset, but the option of manually selecting data to be cached seems to be an obvious advantage in comparison with Smart Response. Besides, the first launch of a previously unused application is performed faster on the HighPoint controller than with Smart Response even in automatic caching mode. The downside is the poor repeatability of the controller's results and its overall lower speed compared to Intel's technology when applications and data are retrieved from the cache.
On the other hand, the benefits of a HyperDuo disk created on a HighPoint RocketHybrid 1220 controller over a conventional HDD are obvious. You may want to buy that controller to accelerate your disk subsystem and make your computer more responsive without having to switch to the Intel Z68 chipset (it is the only chipset as yet to support Smart Response) or to replace your conventional HDD with a large-capacity and expensive SSD.