Intel Matrix Storage + SSD TRIM Pass-through?

[idata]

Hello!

I would like to know if Intel is aware of the issues with SSD's and RAID arrays regarding the lack of TRIM capability. More and more SSD drives support the block cleaning/optimising method aka. TRIM. Windows 7 has the operating system level support for it. As far as the user useres his SSD's in normal SATA/Legacy IDE mode this TRIM methid works because the OS can send the TRIM method calls directly to the drive itself. But if the user's SSD drives are in a RAID0 array TRIM capabilities are gone, because the Intel RAID controller does not pass through the TRIM method calls.

My question is that whether Intel is aware of this problem and if is there any effort to solve this issue? Are we seeing any driver updates soon?

Thank you indavance!

Regards

[idata]

william, it seems you are unawares of the multitude of mlc drives that are available do experience performance degradation w/o the sort of "cleanup" trim offers. regarding raid, i certianly notice the speed difference between using a single drive and 4 in a raid0 array, and would really like to have discard/trim support on my intel based workstation ich (which uses system ram for cache, if i'm not mistaken), which by the way offers very good performance (up to and including x4 ssd) compared to the adaptec you stated you have (i also run one, and the ich option performance is quite close). mlc drives are a bit different than the slc, and can really benefit from trim/discard. even slc can experience similar performance degradation effects over time w/o it's implementation.

[idata]

@m.oreilly

I am aware of what TRIM is, and why it exists, and where it's utilized, and the benefits it could potentially give. However, most people do not see the larger picture. They focus on this one aspect without regard to the whole picture, something which I find usually to be an excuse to just wait.

Let's say TRIM is fully supported. Let's assume wear-leveling is still being used. Let's also assume that, for whatever reason, the system is writing way more data than it reads. Let's also assume SSD is being used for speed and not mass storage. This should cover about 90% of the SSD users out there.

TRIM will only clear pages which have NO data in them. In a typical operating environment, after a period of weeks or months, how many pages do we think would have NO data written on them? Even if it's 1 byte of data, the page has to be re-written like all the others. Without any standard supported defragmentation API for the SSD to create contiguous blocks of data at the page level, how can we be certain there will ever be any empty pages of data again? What good is TRIM if there are no or few pages to actually clear? TRIM cannot do the job by itself.

So, a lot more has to happen before TRIM is remotely useful, but even still -- if TRIM is the most important aspect of the purchase, perhaps we're looking at the wrong solution. With 4 SSD drives in a proper RAID 0 configuration, the amount of performance degradation will be humanly unnoticable -- that is, unless you happen to be writing gigabytes of data every hour.

Most systems read 75-90% of the time, and write 25% of the time or less. Writing is the only times when TRIM would have any effect.

I to not claim to know everything about TRIM or SSDs, but at least I have an operational system and it's much faster than before. Enough that I'd never go back to HDD without a fight.

TRIM is simply not an excuse to wait.

Good luck!

William

[idata]

william, i am 'waiting" for trim and all the goodies that are involved in the standard, but have been enjoying several raided ssd arrays for quite some time, so i don't get this "waiting" you are referring to and yes, i notice when my performance goes down. anything that helps with this is a good thing. at the moment, i have to either do an hdderase or destructively re flash my drives to "restore" them, as being in an array, i am unable to take advantage of the brute force methods of trim that a certain manufacturer has come up with (single drives only). i work and play w/my system, and the drives get used. it almost seems as if you are declaring trim/discard to be some sort of boondoggle.

[idata]

@m.oreilly:

IMHO, TRIM itself is pretty much a boondoggle, or at the very least, not even close to the Holy Grail. Post some links to testing results which show improvement from TRIM in real-world situations -- and NOT from completely erasing a drive (as this is not what TRIM does). In real-world situations, the TRIM command would have very little to clean up without a proper internal defragmentation of the flash pages, and that would have to also need to include swapping data from one page to another to ensure proper wear-leveling.

As I mentioned, if you are writing gigabytes of data, you just might see stacked up speed improvements from a new or majorly "trimmed" drive. Don't forget, it's also possible that if you are seeing slow downs from everyday use, perhaps the SSD isn't the primary issue. Maybe it's RAM and the paging file, or the CPU, or some software? Maybe it's just flat out cheap SSD hardware? I have a strong feeling SSD speeds will quickly outpace any benefit TRIM could possibly hope to achieve, and prices are constantly diving.

Is your application a unique one? Please let me know about it so we can share and discuss the results. You said you gain improvement by wiping your drive completely, but it's not what TRIM will do. Therefore, how can you come to a final conclusion that TRIM will address your concern? You might want to take a closer look at what is doing so much writing to your SSDs -- and add on a hardware RAM drive to supplement it.

Good luck!

William

P.S. Do you have documentation to support the fact HDDerase or the other method you use is actually performing the erase function you're looking for? "SECURE ERASE" is not necessarily the same operation as TRIM. If secure erase is working, then perhaps just clearing slack space will also help in your configuration...?

[idata]

this is an intel forum, so i'm not going to espouse another manufacturer's product/FW. suffice to say if you google a certain popular company's sata/flash support forum,you will notice that many patrons of that site are indeed recouping drive performance using a proprietary app and drive FW capable of carrying out trim commands. i know what trim doesn't do, and i don't know why you are not being more supportive of the standard which will allow improved performance and broader acceptance of ssds. william, it's time to move forward, there is nothing to be gained by the dragging of feet. enjoy your drives