Dell Precision M6700 Owners Thread

Yes. That's exactly it. You get the full capacity of your hard drive and set aside part of your SSD to act as a cache. I have mine set up to cache both reads and writes, which basically gives me SSD speeds for most I/O with the huge, cheap storage offered by the HDD for files which simply don't need lightening access speeds such as music and video files which will be played back at "normal" speeds. This setup also means that I am not wasting valuable SSD storage on OS files that never see the light of day, such as unused drivers, backups, cab files etc..

In my case my SSD is 256GB and I have set aside the maximum of 64GB as a cache for the HDD. The rest of the SSD is available to use as I see fit for other fast access. I use it for separate cache and preview storage for Adobe Lightroom. Any raw image files I am actively working on also reside on the SSD and once I'm done with them they get archived off to the HDD where they can sit, dormant, and leaving my more important/current stuff to benefit from the SSD.

 

thank you all for replying to my question regarding K4000 vs K5000...
i think that definitely a K5000 is overkill for my uses and am happy with my selection.

now the waiting begins...

 

Thanks for the info. So, you're basically not using your SSD as a boot partition, but have dedicated 64 GBs of it for cache. And Intel Rapid Storage driver handles this cache or is it the Windows (i.e. that Windows ReadyBoost feature?)? So, basically, it is somewhat like the Seagate Momentus XT, just handled by software and not by the drive itself as in the latter? Too bad the M6400 doesn't have the mSATA slot as I've been toying with the idea of replacing the 320 GB drives in RAID-0 with two Seagate Momentus XT drives, though it can fit that FCM(?) flash memory card, but those are only like 4-5 GBs in size if I remember correctly.

 

Yep. My personal opinion, which is probably not wrong, is that installing the OS to the SSD is going to waste a lot of space for files which will be of no value in daily use. By setting things up as I have done the dead weight is left on the HDD and only the interesting files get copied to the SSD. Not only that, but the most important 64GB of files from my 750GB HDD are cherry picked by the system to enjoy high speed privileges. Then I have the rest of the SSD to use as I please.

If I installed the OS to the SSD in the first place then I'd lose the caching facility and would have to be very selective about which files I chose to place on the SSD. Everything else would have to suffer slow response times from the HDD, whether important to system responsiveness or not.

The heavy lifting is done by Intel's Smart Response Technology. I haven't read the article, but there is a guide here - How to Set Up Intel Smart Response SSD Caching Technology | PCWorld.

I do have a 750GB Momentus XT drive in my previous laptop - XPS M1710 - but an 8GB cache is pretty meagre compared to 64GB from an SSD. It does work, as analysis of response times by the Resource Monitor will confirm, but is very limited by comparison.

Here is a screen print from Resource Monitor on my M6700 showing response times for my system. Despite the OS residing on the HDD the response times for cached files are impressive.

 

I'm also using Intel SRT to have an SSD accelerate a regular hard drive. In my case, I have a 60 GB mSATA SSD and all of it is devoted to cache. The caching is handled by Intel's drivers with cooperation from Intel's RAID controller on the motherboard, it is a separate technology than Windows ReadyBoost. The HDD+SSD actually form a special RAID volume where only part of the HDD is mirrored. As such, any HDD+SSD combo can be used but both of them have to be connected to SATA ports on the Intel drive controller (i.e. using a USB device for either drive is not an option).

Intel's drivers do a pretty good job deciding what to move over into the cache, and avoid moving things into the cache that wouldn't make sense (i.e. long sequential reads can be handled fine by the HDD).

Apple is doing the same thing with the "fusion drive" in some of their new machines.

It's a good trade-off if you don't want to put down the cash for an SSD large enough to hold everything that you need. (Like tdodd mentioned, if you go for all SSD then you will have a lot of data sitting on the SSD that is not benefiting from the SSD's performance characteristics.) As SSDs decrease in price and the market segment matures, they may become the obvious choice for storage for most situations. For now, though, I think a HDD and SDD mixture makes sense and Intel SRT actually helps make that work rather well.

There are two modes. You can run the SSD as a read-only cache (only reads are accelerated) or a read-write cache. The second option gets you even closer to SSD-like performance but carries some risk, as the data written to the two drives will not always be in sync so if you crash or there is a hardware fault you might end up with an inconsistent volume. I actually had trouble caused by this early on so I am running mine as a read-only cache for safety. Though I think if you don't tinker with the system much, the read-write cache mode is safe.

I'm disappointed that there are no tools to see what the cache is actually doing or get any statistics out of it.... But I can definitely tell that it makes a difference.

Gotchas.
- I recommend disabling the Intel SRT cache before upgrading the Intel rapid storage drivers or the system BIOS. You can enable it again afterwards. Since I got this machine I've had trouble from both of these scenarios and disabling the cache beforehand seems to avoid them. However, you then have to wait for the cache to rebuild before you get your performance back.

 

I have a much different preference. SSDs are great for maximum throughout as seen on sequential file transfers but that isn't their main benefit over HDDs. Instead, it is the random 4K access speeds which is why they make a computer so quick. If you want fast sequential transfer speeds then use a couple of HDDs in RAID0 or RAID5 (both are options on the M6700). In the case of RAID0, just carry an external drive to make nightly backups in case of a failure. In the case of RAID5, use an optical bay hard drive caddy to get 3 HDD ports. Either way, RAID is not a backup so I have an ideological issue with using RAID1 especially in port-limited environments like a laptop but to each his or her own.

Secondly, these days SSDs are expensive but they don't carry the astronomical premiums of the past. Intel SRT was designed for an era where large SSDs were too expensive so people could buy a dedicated (and small and cheap) caching SSD like the Intel 311 which uses SLC NAND (that can handle the pounding a cache will take as opposed to MLC NAND) to accelerate slower HDDs. People can realistically pickup 256GB and larger drives without busting the bank. Samsung's introduction of cheap TLC NAND will only further drive down prices which will further make SRT unnecessary.

I bought the Intel 310 mSATA SSD when it first came out. It was available in 40GB and 80GB options. At 80GB is was a very tight squeeze to get Windows and all the software packages I needed into that space. It took some clever use of hardlinks in Windows to keep unneeded/unused stuff on the RAID0 data drives in that system. That isn't needed anymore. We should see 512GB mSATA SSDs in the near future where it will be even less of a problem.

In my honest opinion, the ideal performance and enormous storage set up on the M6700 is a 256GB mSATA SSD that contains Windows and programs. The drive needs to be "short stroked" to 75% capacity to keep the massive speed benefits of a SSD as described here. For data storage either RAID0 or RAID5 (3 drives minimum). Finally, an external USB or Firewire drive for backup purposes on the go. That's just my opinion.

Apple's Fusion Drive is slightly different than Intel's SRT.

First of all, it is a 128GB (as of now) SSD using the same connector as seen in new MacBook Air and Retina MBP models. That means the controller is either Samsung or Toshiba (I prefer Samsung).

Secondly, unlike SRT, the total volume is cumulative. For example, 1TB hard drive + 128GB SSD shows up as a single volume with 1.1TB of available storage.

Thirdly, Apple creates a 4GB write buffer on the NAND. Writes larger than that hit the hard drive. This uses the SSD's strength at handling small writes that tend to bog down system performance (as I mentioned above). This obviously only helps light workloads. This is the only cache-like component of Fusion Drive.

Everything else works like a pinning algorithm. In other words, OSX physically moves frequently used files and data to the 128GB SSD and less frequently moved items go to the HDD. There is a built-in robustness to deal with power-outages during the transfer process. Once the transfer is complete there is only one copy of the item on the system (either on the SSD or HDD).

There is no (simple) user interface to manage any of this because it is handled by OSX. Obviously, a larger SSD and larger write cache will help power users but it is not available right now.

I find the idea behind Fusion Drive to be slightly better than SRT but, again, it is a band-aid until prices drop further. I'd much rather have a SSD for the operating system and HDD for data storage until 1TB SSDs or larger show up (and don't carry an extra $/GB cost premium).

Where SRT makes sense is on the desktop where post-limits aren't as much of an issue. Using an old SSD to accelerate a HDD-based RAID is a no-brainer but beyond that the use of SRT is suspect.

That's my opinion/preference. It isn't meant to offend anyone.

 

What is recommended with regards to the free fall sensor when there is both an SSD system drive and a traditional secondary hard drive.

Disable the sensor, or enable and install the software?

This is related to configuring a large number of identical machines for corporate use.

Thanks

 

If there is at least one HDD in there, i would keep it on for sure.

 

Yes. Exactly. And the caching algorithm is designed to make best use of the cache space for files which need fast random access. It won't bloat the cache with video files and things like that. Equally it won't bloat the cache with files which will never be used, such as all sort of files related to Windows features, services, drivers, update backups, restore points and so on which will simply occupy space and not benefit in any way from sitting on fast storage. If you install your OS to the SSD you can be sure that quite a few GB will be wasted on redundant/dormant files.

Suppose you install lots of software to your OS partition. Photoshop would be an example. That's a pretty big package and, for my purposes, a significant amount of the software is bloat which I'll never ever use. It is pointless to gobble up valuable SSD space on things I will never use. I don't know the architecture of games software - I don't play PC games - but no doubt one install will amount to several GB of data. How much of that requires immediate response vs fast sequential access? The caching algorithm will sort it out for you. As you move on to install and play different games the cache will adjust to what becomes relevant. If this was all installed directly to the SSD it would begin to fill up quite quickly.

To put this another way, my machine was delivered with 256GB mSATA and 750GB HDD. That's how I wanted it. I like the concept of ISRT. Personally I would not gain a thing by replacing my HDD with an SSD or two other than a large bill and reduced storage capacity. Admittedly the bill would not be as large today as once it might have been, but it is a bill I can happily avoid completely without penalty.

I do back up to an external drive when it is timely to do so (i.e. when I import a bunch of new photos to work on) and my daily documents and personal files are synced with the cloud as they are updated and copied down to other machines as and when I use them. I have no concerns about data loss.

At the end of the day we all have our own needs and preferences. Since I clean installed Windows 8 on my machine I could have set it up however I liked, including installing the OS to the mSATA SSD. In fact I have a full sized 256GB SSD I could harvest from my travel laptop and use that as a boot drive but quite frankly it made no sense to me to do that. ISRT is the sweet spot for me. Your mileage may vary.

 

Just saw that Dell has the Nvidia 306.68 A02 drivers up. Have not seen drivers this new posted this fast before.