Z68 ssd caching: SSD Caching — Intel Z68 Chipset & Smart Response Technology (SSD Caching) Review

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IntroductionSSD CachingIntel’s SSD 311 20GB: Designed to CacheApplication & Game Launch Performance: Virtually Indistinguishable from an SSDThe Downside: ConsistencyAnandTech Storage Bench 2011 — Heavy WorkloadAnandTech Storage Bench 2011 — Light WorkloadFinal Words

SSD Caching

We finally have a Sandy Bridge chipset that can overclock and use integrated graphics, but that’s not what’s most interesting about Intel’s Z68 launch. This next feature is.

Originally called SSD Caching, Intel is introducing a feature called Smart Response Technology (SRT) alongside Z68. Make no mistake, this isn’t a hardware feature but it’s something that Intel is only enabling on Z68. All of the work is done entirely in Intel’s RST 10.5 software, which will be made available for all 6-series chipsets but Smart Response Technology is artificially bound to Z68 alone (and some mobile chipsets—HM67, QM67).

It’s Intel’s way of giving Z68 owners some value for their money, but it’s also a silly way to support your most loyal customers—the earliest adopters of Sandy Bridge platforms who bought motherboards, CPUs and systems before Z68 was made available.

What does Smart Response Technology do? It takes a page from enterprise storage architecture and lets you use a small SSD as a full read/write cache for a hard drive or RAID array.

With the Z68 SATA controllers set to RAID (SRT won’t work in AHCI or IDE modes) just install Windows 7 on your hard drive like you normally would. With Intel’s RST 10.5 drivers and a spare SSD installed (from any manufacturer) you can choose to use up to 64GB of the SSD as a cache for all accesses to the hard drive. Any space above 64GB is left untouched for you to use as a separate drive letter.

Intel limited the maximum cache size to 64GB as it saw little benefit in internal tests to making the cache larger than that. Admittedly after a certain size you’re better off just keeping your frequently used applications on the SSD itself and manually storing everything else on a hard drive.

Unlike Seagate’s Momentus XT, both reads and writes are cached with SRT enabled. Intel allows two modes of write caching: enhanced and maximized. Enhanced mode makes the SSD cache behave as a write through cache, where every write must hit both the SSD cache and hard drive before moving on. Whereas in maximized mode the SSD cache behaves more like a write back cache, where writes hit the SSD and are eventually written back to the hard drive but not immediately.

Enhanced mode is the most secure, but it limits the overall performance improvement you’ll see as write performance will still be bound by the performance of your hard drive (or array). In enhanced mode, if you disconnect your SSD cache or the SSD dies, your system will continue to function normally. Note that you may still see an improvement in write performance vs. a non-cached hard drive because the SSD offloading read requests can free up your hard drive to better fulfill write requests.

Maximized mode offers the greatest performance benefit, however it also comes at the greatest risk. There’s obviously the chance that you lose power before the SSD cache is able to commit writes to your hard drive. The bigger issue is that if something happens to your SSD cache, there’s a chance you could lose data. To make matters worse, if your SSD cache dies and it was caching a bootable volume, your system will no longer boot. I suspect this situation is a bit overly cautious on Intel’s part, but that’s the functionality of the current version of Intel’s 10.5 drivers.

Moving a drive with a maximized SSD cache enabled requires that you either move the SSD cache with it, or disable the SSD cache first. Again, Intel seems to be more cautious than necessary here.

The upside is of course performance as I mentioned before. Cacheable writes just have to hit the SSD before being considered serviced. Intel then conservatively writes that data back to the hard drive later on.

An Intelligent, Persistent Cache

Intel’s SRT functions like an actual cache. Rather than caching individual files, Intel focuses on frequently accessed LBAs (logical block addresses). Read a block enough times or write to it enough times and those accesses will get pulled into the SSD cache until it’s full. When full, the least recently used data gets evicted making room for new data.

Since SSDs use NAND flash, cache data is kept persistent between reboots and power cycles. Data won’t leave the cache unless it gets forced out due to lack of space/use or you disable the cache altogether. A persistent cache is very important because it means that the performance of your system will hopefully match how you use it. If you run a handful of applications very frequently, the most frequently used areas of those applications should always be present in your SSD cache.

Intel claims it’s very careful not to dirty the SSD cache. If it detects sequential accesses beyond a few MB in length, that data isn’t cached. The same goes for virus scan accesses, however it’s less clear what Intel uses to determine that a virus scan is running. In theory this should mean that simply copying files or scanning for viruses shouldn’t kick frequently used applications and data out of cache, however that doesn’t mean other things won’t.

Introduction
Intel’s SSD 311 20GB: Designed to Cache
IntroductionSSD CachingIntel’s SSD 311 20GB: Designed to CacheApplication & Game Launch Performance: Virtually Indistinguishable from an SSDThe Downside: ConsistencyAnandTech Storage Bench 2011 — Heavy WorkloadAnandTech Storage Bench 2011 — Light WorkloadFinal Words

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What Intel Z68 SSD caching means for iMac owners

Apple’s new iMac systems came with a little surprise, which was the inclusion of the new Z68 chipset from Intel. This chipset supports a number of enhancements over the previous versions used, and Apple has already enabled some of these with a recent firmware update that unlocked SATA III capabilities in the new systems. Beside SATA III, however, the chipset does boast another speed-enhancing technology called SSD caching, but unfortunately for now iMac owners will not be able to use this.

SSD caching is a technology that uses up to 64GB of a high-speed SSD device to store frequently accessed items normally kept on a slower mechanical drive. The SSD cache is transparent to the user and essentially offers a significant speed boost to an existing mechanical-drive setup. This can result in greatly increased drive performance for a fraction of the price that it would take to match a mechanical drive’s storage capacity an SSD option (currently a 1TB SSD goes for around $3,000, whereas a 64GB SSD and a 1TB mechanical drive would cost around $225).

What this means is a great price/performance for people who need larger drive space. A good majority of a hard drive’s space ends up being used for infrequently accessed long-term storage of music, photos, videos, and rarely used applicaitons, among other files. As a result, getting a large 500GB or greater SSD drive and filling it with these files ends up being a waste of high-performance media space. In practice, only 10-40GB of most hard drives ends up being regularly used.

The solution Intel came up with in the Z68 chipset is to make use of smaller and cheaper SSD drives to cache frequently used items on larger mechanical drives. Therefore, to benefit from fast SSD speeds for everyday work, you just need to purchase a smaller and cheaper SSD drive and pair it up with a larger mechanical drive.

There currently are a few hybrid SSD drives that use a small amount of NAND flash memory to cache frequently accessed contents; however, the difference between these technologies may lie in how they manage the caching but also in the size of the cache. Currently Hybrid SSD drives like the Seagate Momentus XT line use about 4GB of NAND memory, as opposed to Intel’s approach that allows the cache size to be scaled up to 64GB depending on uses.

The real benefit of the Z68 caching technology is you can turn an older mechanical drive setup into a SSD hybrid setup by adding a small and relatively cheap SSD drive to your system (a 32GB SSD drive is around $80 these days, and a 64GB SSD is around $150). All it would take to significantly increase the speed of your computer is to install one of these drives and everything would be snappier for you, without having to migrate your data to a new drive.

So what does this mean for Apple’s iMacs? Ultimately to benefit from the caching features of the Z68, the system will need to be able to hold both a standard drive and a solid-state drive, as well as have driver support for this feature. The new iMacs have all that’s needed in the hardware to take advantage of the new caching features; however, Apple so far has not implemented or enabled in OS X. Therefore, despite the potential for increased speed in the new systems, iMac owners will have to wait to see if Apple will make use of this feature.

In the meantime, Mac users can use Apple’s currently supported options:

1. Pure SSD Drive

   The fastest solution will always be to use a pure SSD option, so if you can stomach the cost of larger SSD drives, then that is one route.

2. Combo SSD and mechanical drives

   This option will allow you to better tailor your Mac’s drive setup for performance without paying so much for larger SSD drives. You can get a small 80-160GB SSD drive to hold OS X and your applications so they launch fast, and then setup your file-system structure to have large and infrequently used files be stored on a secondary mechanical drive.

   The drawbacks to this are that it will take some setup for individual applications and conscious organization of your files to keep large and long-term storage on the mechanical drive (most applications will store libraries by default to the home folder, which is on the boot drive). Despite this, with this setup, if Apple ever enables SSD caching support, then you will be able to take advantage of it for the mechanical drive and speed up its performance as well.

3. Hybrid drive

   The last option is to install a SSD hybrid option such as the Seagate Momentus XT, which currently uses a 4GB SSD cache to increase the drive’s performance.

Questions? Comments? Have a fix? Post them below or e-mail us!
Be sure to check us out on Twitter and the CNET Mac forums.

Trying Smart Response on the tooth / Sudo Null IT News

Intel Blog Article “Upgrade Your Hard Drive. This way really works! ”, dedicated to Smart Response technology, has collected more than a hundred comments and, it seems, only slightly less polar opinions about whether this thing works and why it is needed at all. Observing such a habra interest, we decided to conduct our own SRT tests in order to try to answer the first, and, if possible, then the second question.
To test our preliminary hypotheses (which will be discussed below), we decided to use a typical home platform that has become a truly classic over the past year: Intel Z68 + Intel i5. In more detail, our test bench is described as follows:

• Processor — Intel i5 2500K;
• Motherboard — ASUS P8Z68-V LX;
• System hard drive — Seagate ST500DM002;
• SSD drive — Intel SSDSA2MH080G1GC;
• RAM — 8 GB DDR3-1333;
• Operating system — Windows 7 x64.

As you can see, our test computer is not worthy of any claims in extremeness; all its components are from the mass segment, closer to the budget. nine0003

Far from the latest Intel SSD model that we used in testing

Preparing

First, we needed to connect an SSD drive to our computer as a caching device. To do this, we (and you) will need:

• Direct SSD;
• Motherboard with SRT support;
• Intel Rapid Storage drivers (downloaded from the Intel site).

Here is a short instruction on enabling Smart Response. In the motherboard BIOS, the SATA controller is set to RAID mode. There is one caveat here: if you used IDE / AHCI mode before and had Windows already installed, it most likely won’t boot up just like that anymore. In order not to rearrange Windows, you can use the advice from this article — it helped us. We have nothing more to do in the BIOS — we load Windows and install the Rapid Storage drivers. Note that drivers simply will not be installed on a computer with non-RAID enabled. nine0004

Smart Response configured. Internal system disk — «with acceleration». Volume_0001 is the cache itself, Volume_0000 is the remainder of the disk after subtracting 64 GB of cache. The user can handle it at his own discretion.

On the first tab of the Rapid Storage control center, click «enable acceleration», select the necessary parameters (this process is shown step by step at the same link) — and voila! caching is enabled. It can work in two modes: advanced — simultaneous recording on HDD and SSD (in a sense, RAID1) and maximum — recording first on SSD (in the same sense, RAID0). We were interested in the maximum increase in speed, so we chose the second one. Note, however, that in this case, the SSD becomes part of the system partition and any emergency shutdown of it will have unpleasant consequences for the OS. To disable the cache, use the regular procedure of the Rapid Storage driver. nine0004

Experiment

Since Smart Response is a caching technology, it would be logical to test its effectiveness on “heavy” OS applications. The heaviest Windows application is obviously Windows itself. Further, Adobe Photoshop CS6 and Autodesk AutoCAD 2013 were chosen as standards of «common severity». The loading time of each program was measured three times, between two calls the system was rebooted. Average test results are shown in the table:

	SRT off, sec	SRT enabled, sec	Growth, times
Windows 7 x64	101	36	2. 8
Photoshop CS6	15	4	3.75
AutoCAD 2013	53	8	6.6

As they say, know the comments. nine0003
On a less scientific basis, other programs that were at hand were also tested, for example, Corel Draw X4 showed an approximately twofold increase. I foresee the question, why did the system take so long to load without caching? For the experiment, I deliberately chose second-hand Windows, installed several months ago and overgrown with a certain number of applications during this time, including those with autoload. In order to avoid the completely unexplained impact of torrents on caching, distributions were disabled for the duration of the experiment. nine0004

Application

So, we have experimentally proven that Smart Response significantly speeds up Windows and its applications. However, the question still remains, why use an SSD for caching when you can just place a system partition on it? The experiment confirmed a number of our assumptions.

Test computer against the background of the carpet — so that no one has any doubts that we are talking about a Regular Home PC.

1. Old or budget SSD models, relatively slow and small in volume, can be assigned to caching. Note that the gain numbers shown above were obtained on a SATA2 SSD. Size also matters: say a 60 GB SSD may not be enough for a home computer, especially a gaming one. nine0007
2. Smart Response may also be suitable for disposing of out-of-trust SSDs. The lifetime of solid-state media is short; there comes a time when it is better to transfer the SSD to a less responsible job. SRT, especially in extended mode, is quite a suitable variety of it.
3. Finally, due to the ease of installation and configuration, SRT can be considered as an ideal solution to the problem when you need to quickly wake up the computer to perform some unusual actions. Let’s say you don’t make any big demands on your PC and are quite satisfied with its performance. But here suddenly there is a need to use AutoCAD (for coursework, for example). An SSD can be borrowed or bought cheaply at a flea market — and budget acceleration is ready in 10 minutes. nine0007

In our opinion, the above arguments are quite enough for Smart Response technology to at least have the right to life. Well, to use it or not — your choice, how to do it — we briefly told.

Intel Smart Response Technology.

Intel Smart Response Technology (SRT) is designed to bridge the middle ground between a traditional mechanical hard drive and a solid state drive by combining the two. While high-capacity SSDs are still quite expensive, low-capacity SSDs are much cheaper and achieve a similar level of performance. Intel’s SRT technology allows the use of a low-capacity SSD to improve the performance of a mechanical drive by using the SSD as a cache. nine0003 Until now, there was no middle ground between them. Sure, there are products like the Seagate Momentus XT hybrid hard drive that boosts read speeds with 4GB of read cache, but in most tests they can be easily beaten with Western Digital’s VelociRaptor hard drives.

SSD caching is actually nothing new and has been around for several years in various forms such as Intel Turbo Memory Technology (also known as Robson Technology) which was launched in 2006. But since its launch, it has not gained much popularity. An Intel Z68 chipset that supports SRT I/O caching. nine0004

Smart Response technology improves performance by keeping files or parts of files you access most often on the SSD for faster access. The SRT software can only cache some files because there is limited space on the SSD, so it determines the most useful files to cache by keeping track of which programs and files you use the most. It can also identify files that you are likely to use once or twice, such as audio and video files. nine0004

Because the software must learn your behavior, the performance benefits of SRT will not be immediately noticeable. But the software can adapt to your habits over time, which should bring long-term productivity benefits. Your system will also only display one drive letter despite having two physical drives on your system.

You only need three items to use SRT. This is a motherboard based on the Z68 chipset, an SSD and a hard drive. The SSD and hard drive can be of any capacity, but keep in mind that the SRT can only use up to 64 GB of space on the SSD, so don’t buy a large SSD. nine0004

Intel 311 Series SSD

Intel has released its new 20 GB 311 Series SSD, codenamed Larson Creek, which was specifically designed for use with the SRT. It differs from most SSDs on the market today because it uses SLC memory chips, which typically last much longer than the MLC chips used in most SSDs. This greatly increases the cost of the drive, as SLC chips cost about twice as much as MLC. nine0004

The drive itself is a standard 2.5-inch form factor, which means it should fit most modern PC cases. If not, there are plenty of 2.5″ to 3.5″ adapters available on the market that will cost you just a few dollars. Intel has chosen to use an aluminum case, which should provide good protection to the internal parts of the drive. To remove the case, we must remove the four screws in each corner of the drive.

The drive is equipped with the same Intel PC29 controllerAS21BA0, as well as a number of other solid state drives, as well as 32 MB ISSI cache IS42S16160D-7TLI. This supports maximum read and write speeds of 200MB/s and 105MB/s respectively. There are a total of five SLC memory chips, which are also manufactured by Intel. They carry part number 29F32G08CAND2.

How to set up Smart Response Technology

In most cases, it is not possible to use Smart Response Technology without reinstalling Windows on your PC because you must enable RAID mode in the BIOS to enable SRT. We expect most Z68 motherboards to be set to IDE or AHCI mode by default, like the Gigabyte Z68X-UD5-B3, so you should definitely change this before installing Windows. nine0004

When you install Windows, you must make sure you install it on your hard drive and not on your solid state drive, which must be left empty. After installing Windows, you must install all drivers from the CD that came with the motherboard. On our Gigabyte Z68X-UD5-B3 motherboard, we had to update the BIOS to the latest F6 to get SRT to work. We also had to update the Intel Rapid Storage Technology software to the latest version 10.5.0.1027. Without these updates, after enabling SRT, the system simply will not boot. nine0004

After restarting the computer, you will be able to run the Intel Rapid Storage Technology software to set up the SRT. On the top menu bar, you must click on the «Accelerate» button, which opens another window that allows us to select the SSD to be cached and the disk volume or RAID volume you want to accelerate. You can also choose between two acceleration modes: advanced or maximum.

Two different modes configure SSD caching differently. Advanced mode is designed for maximum security, reduces the chance of data loss, and also limits the write speed as it writes data to the SSD and HDD at the same time. Maximum mode is for optimal performance, writing data to the SSD and only periodically transferring it to the hard drive. This means that if something goes wrong with the SSD, you may lose some data. The outcome of an SSD crash will largely depend on what the SSD was caching at the time of the crash, so it’s hard to predict how it will affect your system. nine0004

How we tested

During our testing procedures, we used the configuration below. The only variable component between each testing session was the drive being tested.

Hardware Configuration

Processor: Intel Core i5-2500K
Motherboard: Gigabyte Z68X-UD5-B3
Memory: Dual 2GB Kingston HyperX Genesis (DDR3-2133, CL9, 1. 6V, 9-9 -9-27)
Video card: AMD Radeon HD 6950
Video resolution: 1920 x 1080
Video Monitor: Viewsonic VX2260WM
Power Supply: Corsair HX850W
CPU Cooler: Noctua NH-D14
Test Drive (1): Samsung Spinpoint F3 (HD103SJ) 1TB 7200rpm + Intel 311 Series 20GB
Test Drive (2): Samsung Spinpoint F3 (HD103SJ) 1TB 7200rpm
Test Drive (3): Kingston SSDNow V+ 100 128GB

Software Configuration

Operating System: Windows 7 Home Premium 64-bit with NTFS 9 file system0003 Intel INF Driver Version: 9.2.0.1016
AMD Video Driver Version: Catalyst 11.5

Benchmarking Software

CrystalDiskMark 3.0.1 x64
PCMark 7
PCMark Vantage

3%, which means that performance differences of less than 3% cannot be considered significant. Therefore, when the performance difference between two products is less than 3%, we consider that they have the same performance. nine0004

CrystalDiskMark

As you already understood, we measured the performance of Smart Response Technology using three different programs: CrystalDiskMark, PCMark Vantage and PCMark 7. We will consider the test results with each program in the order they appear in the list above.

It’s important to note that we’ve connected all drives to SATA-600 ports on the motherboard, not SATA-300 ports, which may result in performance degradation.

We’ve included results for the Kingston SSDNow V+ 100 SSD for all the tests we ran to give you an idea of ​​how SRT compares to having an SSD as your main drive. nine0004

For our tests, we used CrystalDiskMark’s default configuration, which compared each SSD to a 1000MB file size over five test runs. Please read on to see the results.

In the sequential read test, Smart Response technology in expanded mode gave an impressive performance boost of 38.1% over a hard drive. In advanced mode, the performance gain was 59.5% compared to a single hard drive. In both sequential write tests with SRT, there was a 7.4% performance drop compared to the hard drive at maximum mode and a 10% performance drop. nine0004

This could be for a number of reasons. The displayed results were recorded on the third run of the test to give the system a chance to «learn» our behavior. After even more iterations of the test, performance should improve as the system caches more data. But the maximum write speed of the Intel 311 Series SSD is 105 MB/s, which is probably the limiting factor in this case. Since the maximum hard disk write speed is higher, data caching actually negatively impacts performance in this test. nine0004

In the random read test using 512 KB blocks, performance was significantly better than in the sequential test. In the maximum mode, performance increased by 249%, and in the advanced mode — by another 272%. In a random write test using 512K blocks, performance was not improved with SRT enabled in advanced mode. But in the maximum mode, performance increased by 84%.

With SRT enabled in maximum mode, hard disk test performance increased significantly by 4434% compared to a single hard disk in the random read test and by 3714% in the write test using 4 KB blocks. At max mode, the SRT also outperformed the Kingston V+ 100 128GB SSD by 13% in the read test and 50% in the write test using 4K blocks. nine0004

But when SRT was enabled in advanced mode, there was no improvement over the standard hard disk in the write test using 4 KB blocks. However, in the read test using 4K blocks, there was an impressive improvement of 4586%.

PCMark

To test the performance of Smart Response technology, we decided to use both PCMark Vantage and PCMark 7 as they give us a good idea of ​​real-time performance. Read on to see the results. nine0004

In the Windows Startup test, we saw a huge performance improvement of 468% in maximum mode and 472% in advanced mode. In the game and app load tests, we saw performance increases of 592% and 1383% in the maximum mode and 564% and 1378% in the advanced mode. There was also an impressive performance increase in the add music test of 501% in maximum mode and 481% in advanced mode.

Application launch test has seen significant improvements in both advanced and maximum modes — 951% and 981% respectively. In the add music test, performance improvements with SRT were much smaller, with a 7% improvement in maximum mode and a 3.1% improvement in advanced mode.

Moving on to the gaming test, the improvement in the maximum mode was 199%, and in the advanced mode it was 194% better than the hard drive. We also saw reasonable performance gains in the Windows Defender benchmark, where performance was increased by 190% in Max mode and 185% in Enhanced mode. nine0004

Conclusions

In our tests, we saw a pretty impressive performance boost with Smart Response technology enabled, compared to using caching on the hard drive itself. It was actually better than the SSDow King + SSDNow V + 100 in some tests.

There have been a few instances where SRT has had a negative impact on performance, but that’s because SRT only caches the most frequently accessed data. This means that tests that measure performance by reading all sectors of a disk will not benefit from SRT like CrystalDiskMark’s sequential write test.