Intel Z68 Chipset & Smart Response Technology (SSD Caching) Review
by Anand Lal Shimpi on May 11, 2011 2:34 AM ESTThe Downside: Consistency
Initially it's very easy to get excited about Intel's SRT. If you only run a handful of applications, you'll likely get performance similar to that of a standalone SSD without all of the cost and size limitations. Unfortunately, at least when paired with Intel's SSD 311, it doesn't take much to kick some of that data out of the cache.
To put eviction to the test, I ran through three games—Portal 2, Starcraft 2 and World of Warcraft—then I installed the entire Adobe CS5.5 Master Collection, ran five of its applications and tried running Starcraft 2 again. All of Starcraft 2's data had been evicted from the SSD cache resulting in HDD-like performance:
| Starcraft 2 Level Loading—Seagate Barracuda 3TB (Maximize Cache) | |||||
| Load Time | Load Time After App Install/Launch | ||||
| Game Launch | 9.7 seconds | 17.4 seconds | |||
| Level Load | 15.0 seconds | 23.3 seconds | |||
I thought that may have been a bit excessive so I tried another test. This time I used the machine a bit more, browsed the web, did some file copies and scanned for viruses but I didn't install any new applications. Instead I launched five Adobe applications and then ran through all of our game loading tests. The result was a mixed bag with some games clearly being evicted from the cache and others not being touched at all:
| Game Load Comparison | ||||||||
| Intel SSD 311 20GB Cache | Portal 2 (Game Launch) | Portal 2 (Level Load) | Starcraft 2 (Game Launch) | Starcraft 2 (Level Load) | World of Warcraft (Game Launch) | World of Warcraft (Level Load) | ||
| Load Time | 9.9 seconds | 15.1 seconds | 9.7 seconds | 15.0 seconds | 4.5 seconds | 5.8 seconds | ||
| Load Time After Use | 12.1 seconds | 15.1 seconds | 10.1 seconds | 15.3 seconds | 3.6 seconds | 14.0 seconds | ||
Even boot time was affected. For the most part performance didn't fall back down to HDD levels, but it wasn't as snappy as before when I was only running games.
| Boot Time—Seagate Barracuda 3TB (Maximize Cache) | ||||
| Time | ||||
| Boot Time | 32.6 seconds | |||
| Boot Time After Use | 37.3 seconds | |||
| Boot Time Without Cache | 55.5 seconds | |||
Although Intel felt that 20GB was the ideal size to balance price/performance and while SRT is supposed to filter out some IO operations from being cached, it's clear that if you frequently use ~10 applications that you will evict useful data from your cache on a 20GB SSD 311. For lighter usage models with only a few frequently used applications, a 20GB cache should be just fine.
There's also the bigger problem of the initial run of anything taking a long time since the data isn't cached. The best way to illustrate this is a quick comparison of how long it takes to install Adobe's CS5.5 Master Collection:
| Install Adobe CS5.5 Master Collection | ||||
| Time | ||||
| Seagate Barracuda 3TB (No cache) | 13.3 minutes | |||
| Seagate Barracuda 3TB (Maximize Cache) | 13.3 minutes | |||
| OCZ Vertex 3 240GB (6Gbps) | 5.5 minutes | |||
A pure SSD setup is going to give you predictable performance across the board regardless of what you do, whereas Intel's SRT is more useful in improving performance in more limited, repetitive usage models. Admittedly most users probably fall into the latter category.
In my use I've only noticed two reliability issues with Intel's SRT. The first issue was with an early BIOS/driver combination where I rebooted my system (SSD cache was set to maximized) and my bootloader had disappeared. The other issue was a corrupt portion of my Portal 2 install, which only appeared after I disabled by SSD cache. I haven't been able to replicate either issue and I can't say for sure that they are even caused by SRT, but I felt compelled to report them nevertheless. As with any new technology, I'd approach SRT with caution—and lots of backups.
Facebook
Twitter
RSS
106 Comments
View All Comments
cbass64 - Wednesday, May 11, 2011 - link
Who says you can't use your old 100 or 256GB SSD as an SRT device? The article clearly states that you can use whatever size drive you want. Up to 64GB of it will be used for cache and the rest can be used for data. If you have more than 64GB of data that you need to have cached at one time then SRT isn't the solution you should be looking into.As for OS limitations...you can't seriously think Intel would wait until they had this running on every platform imaginable before they released it to the public, can you? This is the first version of the driver that supports it so of course it will have limitations. You can't expect a feature of a Windows-only driver to be supported by a non-Windows OS. I'm sure this feature will be available on Linux once Intel actually makes a Linux RST driver.
futrtrubl - Wednesday, May 11, 2011 - link
And don't forget that if you don't partition the rest of the space on the SSD it will use it for wear levelling, which will be even more important in this situation.Shadowmaster625 - Wednesday, May 11, 2011 - link
I still dont get why western digital doesnt take 4GB of SLC and solder it onto the back of their hard drive controller boards. It's not like they dont have the room. Hopefully now they will do that. 1TB +4GB SLC all for under $100 in one package, with 2 sata ports.mamisano - Wednesday, May 11, 2011 - link
Seagate has the Momentus 500gb 7200rmp drive with 4GB SLC. It's in 2.5" 'Notebook' format but obviously can be using in a PC.I am wondering why such a drive wasn't included in these tests.
jordanclock - Wednesday, May 11, 2011 - link
Because, frankly, it sucks. The caching method is terrible and barely helps more than a large DRAM cache.Conficio - Wednesday, May 11, 2011 - link
What is the OS support on those drivers (Windows?, Linux?, Mac OS X?, BSD?, Open Source?, ...)?Does the SRT drive get TRIM? Does it need it?
"With the Z68 SATA controllers set to RAID (SRT won't work in AHCI or IDE modes) just install Windows 7 on your hard drive like you normally would."???
Is there any optimization to allow the hard drive to avoid seeks? If this all happens on the driver level (as opposed to on the BIOS level) then I'd expect to gain extra efficiency from optimizing the cached LBAs so as to avoid costly seeks. In other words you don't want to look at LBAs alone but at sequences of LBAs to optimize the utility. Any mention of this?
Also one could imagine a mode where the driver does automatic defragmentation and uses the SSD as the cache to allow to do that during slow times of hard drive access. Any comment from Intel?
Lonesloane - Wednesday, May 11, 2011 - link
What happened to the prposed prices? If I remember correctly the caching drive was supposed to cost only 30-40$?Now with 110$, the customer should better buy a "real" 60GB SSD.
JNo - Thursday, May 12, 2011 - link
+1It's interesting, Anand has a generally positive review and generally positive comments. Tom's Hardware, which I generally don't respect nearly as much as Anand, reviewed SRT both a while back and covered it again recently and is far less impressed as are its readers. I have to say that I agree with Tom's on this particular issue though.
It is *not* a halfway house or a cheaper way to get most of the benefit of an SSD. For $110 extra plus the premium of a Z68 mobo you may as well get an SSD that is 40-60GB bigger than Larson Creek (or 40-60GB bigger than your main system SSD) and just store extra data on it directly and with faster access and no risk of caching errors.
For those who said SRT is a way of speeding up a cheap HTPC - it doesn't seem that way as it's not really cheap and it won't cache large, sequential media files anyway. For those who said it will speed up your game loadings, it will only do so for a few games on 2nd or 3rd run only and will evict if you use a lot of different games so you're better off having the few that count directly on the SSD anyway (using Steam Mover if necessary).
For your system drive it's too risky at this point or you need to use the Enhanced mode (less impressive) and to speed up your large data (games/movies) it's barely relevant for the aforementioned reasons. For all other scenarios you're better off with a larger SSD.
It's too little too late and too expensive. The fact that it's not worth bothering is a no brainer to me which is a shame as I was excited by the idea of it.
Boissez - Wednesday, May 11, 2011 - link
Could one kindly request for the numbers from both the 64GB C300 and 20GB sans harddisk 311 to be added. It would give a good idea of the performance hit one could expect for using these in SRT vs as a standalone boot drive.Boissez - Wednesday, May 11, 2011 - link
First sentence should be: "Could one kindly request for the numbers from both the 64GB C300 and 20GB 311 sans harddisk to be added?"... sorry