MOTUnation.com

Found this nice discussion of how Trim and Garbage Collection ("GC") work together at http://www.thessdreview.com/daily-news/ ... d-primer/2

(T)he TRIM command enables the OS to notify the SSD that old data is no longer valid about the time it deletes the logical block addresses from its logical table. The advantage of the TRIM command is that it enables the SSD’s GC to skip the invalid data rather than moving it, thus saving time not rewriting the invalid data. This results in a reduction of the number of erase cycles on the flash memory and enables higher performance during writes. The SSD doesn’t need to immediately delete or garbage collect these locations it just marks them as no longer valid.

Cindori (who developed the very easy to use Trim Enabler software available at https://www.cindori.org/software/trimenabler) had this to say at MacRumors:

As for OWC drives and Trim in general, their drives support Trim, and use Trim in Windows, so saying it's bad for the drive is quite... contradicting. In fact, by the design of Trim, it's not forced by the OS (or by Trim Enabler), but rather, it's a request that is sent to the drive controller, which then can decide for itself if it should perform the Trim.

I'll post this on the Trim Sticky, too.

My boot drive is an OWC Mercury Electra 6G SSD which has gradually become slower over the past 4 years. It eventually bottomed out at read/write speeds of around 105MB/Sec (when it was 70% full), as slow as my spinning hard drives. I finally enabled trim a couple of weeks ago and the write speeds dropped down a little to <100MB/Sec, but the read speeds jumped to above 150MB/Sec. At OWC's recommendation, I tried reformatting it and cloning the data back to it, but it didn't make a difference. It's out of warranty, so I'm giving up on it and replacing it with a larger drive in the hopes that the next one might last longer.

chadd wrote:My boot drive is an OWC Mercury Electra 6G SSD which has gradually become slower over the past 4 years. It eventually bottomed out at read/write speeds of around 105MB/Sec (when it was 70% full), as slow as my spinning hard drives. I finally enabled trim a couple of weeks ago and the write speeds dropped down a little to <100MB/Sec, but the read speeds jumped to above 150MB/Sec. At OWC's recommendation, I tried reformatting it and cloning the data back to it, but it didn't make a difference. It's out of warranty, so I'm giving up on it and replacing it with a larger drive in the hopes that the next one might last longer.

One can only wonder if things would have been better with Trim enabled all along… I do recall reading that certain Sandforce controllers (OWC uses such controllers in many of their SSDs) can be backed into a corner from which Trim will not restore full performance.

I might suggest you shop around outside of OWC, as much better drive values are available elsewhere…

HCMarkus wrote:

chadd wrote:My boot drive is an OWC Mercury Electra 6G SSD which has gradually become slower over the past 4 years. It eventually bottomed out at read/write speeds of around 105MB/Sec (when it was 70% full), as slow as my spinning hard drives. I finally enabled trim a couple of weeks ago and the write speeds dropped down a little to <100MB/Sec, but the read speeds jumped to above 150MB/Sec. At OWC's recommendation, I tried reformatting it and cloning the data back to it, but it didn't make a difference. It's out of warranty, so I'm giving up on it and replacing it with a larger drive in the hopes that the next one might last longer.

One can only wonder if things would have been better with Trim enabled all along… I do recall reading that certain Sandforce controllers (OWC uses such controllers in many of their SSDs) can be backed into a corner from which Trim will not restore full performance.

I might suggest you shop around outside of OWC, as much better drive values are available elsewhere…

Sandforce controllers have a bad rep because of things like this.

HCMarkus wrote:One can only wonder if things would have been better with Trim enabled all along…<sic>I might suggest you shop around outside of OWC, as much better drive values are available elsewhere…

I was wondering the same thing myself. I didn't even know about trim until a few weeks ago when I started researching why my machine was feeling sluggish. There is updated firmware for that OWC SSD, which I was hoping would help trim recover some performance. Unfortunately, the OWC firmware updater won't recognize it as an OWC SSD, so I was never able to update it.

I ordered a Samsung 850 EVO to replace it. I was willing to pay a premium for the OWC drive in 2011 because I believed the marketing about OWC drives being immune to slowing over time like other SSDs. Not this time.

Sandforce controllers have a bad rep because of things like this.

And now Sandforce is owned by Seagate.

The next generation of controllers, i. e. the ones promised last February at the latest, have been announced and are expected to hit the market sometime around September.

Last week, SanDisk has announced a couple of 2T SSDs for the enterprise market but there's no word on pricing yet nor if a consumer version will follow. Their current 2T offering is priced around $2,850. As much as I would like to install one in my iMac, I don't want one that much.