A couple tricks and fastest options for SSDs out now.

[philbrown]

Helpful info, HC. Much appreciated. I'm starting to get the various concepts and tradeoffs a little better.

[philbrown]

I'm looking at this one for my data drive:
http://www.newegg.com/Product/Product.a ... 1JM0YR5025

I googled this but I'm not understanding what power adapter makes this work:

System Requirement :
Available PCIE 2.0 1X,2X,4X,8X or 16X slot on PC
Supported OS
SATA Power connector to be connected to the adapter

[HCMarkus]

I'm looking at this one for my data drive:
http://www.newegg.com/Product/Product.a ... 1JM0YR5025

I googled this but I'm not understanding what power adapter makes this work:

System Requirement :
Available PCIE 2.0 1X,2X,4X,8X or 16X slot on PC
Supported OS
SATA Power connector to be connected to the adapter

If you are going to have an SSD physically attached directly to a PCIe card, you will need to get power to that drive from somewhere. You can source that power from any unused SATA power port … the second optical bay: find where the power cable connects to the motherboard (below the bay) and replace the cable with one that will reach to the PCIe bay; or from a power connector in an unused drive bay (sled).

On my 4,1, I accessed power for my additional SSDs from the power port that fed the second optical bay, using a splitter that allows me to power three drives from the single port. Since all but one of my SSDs reside in the upper optical bay (resting comfortably on top of the optical drive, which I moved to the lower bay) I was able to connect three to the splitter without any extension cables.

http://www.tigerdirect.com/applications ... lsrc=aw.ds

[philbrown]

As always, thanks HC!

[Michael Canavan]

OK here is why I'm going with the M.2 on PCIe
Hard disk Speed tests.

Regular 7200rpm terabyte HD hard disc- 97mbs

XP941 M.2 512GB on a PCIe card.- 1,114mbs

The fastest you're going to get off of the internal SATA 3g HD bus is roughly 300mbs

A SATA 6g SSD on the PCIe is going to top out at about 550mbs

So basically compared to rotational disks SSDs are always faster, but using the HD trays or the optical tray for a SSD is a bottleneck.

[HCMarkus]

So basically compared to rotational disks SSDs are always faster, but using the HD trays or the optical tray for a SSD is a bottleneck.

But due to the fast access times SSDs (PCIe or SATA) provide, the bottleneck doesn't feel very tight for most.

[mhschmieder]

Timely discussion. I have once again run out of tricks and am getting tired of having top continuously copy stuff to another drive that can only be on the system drive, delete it, install new software that is inflexible about initial location of content, then copy the stuff back and hope licenses are still seen as valid vs. pirated.

I plan to buy a PCIe based SSD solution within the next 48 hours, before disaster strikes during a recording or mixing session.

Originally I planned to use MPG to support that site (via OWC, with the links tracked), but when I last checked in early December, it was still going to cost around $500 or so (which I can't afford yet).

My main consideration is whether to do RAID 0 striping or not, as Lloyd has always recommended (maybe more important for Photoshop power users than audio professionals?). Unless the data drive also goes SSD, I don't see many benefits for the system drive to use RAID 6, given we have Time Machine and plenty of other options to recover stuff that can always be downloaded and reinstalled anyway (unlike a lot of data; especially project data).

Beyond RAID 0 (which is for performance only; no protection), I've never been sold on the concept outside of must-always-be-on server type applications. And like I said above, typical RAID 0 striping doesn't seem necessary atop all the other speed increases we're already getting.

[mhschmieder]

Would it make sense to install Yosemite on a new PCIe-based SSD system drive, then go about moving software from Mavericks on the optical port-based free-hanging SSD system drive?

[mhschmieder]

Oh, I see the prices are the same as a month or so ago:

http://eshop.macsales.com/shop/SSD/PCIe ... glloyd-mpg

Still slightly over $500 for a 480GB solution, which is my smallest option if going RAID, as I currently have 120GB without RAID and have under 1GB of free space left (and lots of instability due to how much stuff I moved off the system drive that is safer left in its default location -- especially after multiple software updates start to "lose" the sense of honoring aliases and preference or plist.info file specifics).

Is there another strategy? I'm overwhelmed by the number of options and how specific each one is to a particular architecture. Also, it seems that "Digilloyd" hasn't updated much at his site in almost two years now, so I don't know how reliable that site is for making SSD decisions on a MacPro 2010 model.

[HCMarkus]

MH, I haven't really explored the PCIe SSD option as I have been very happy with SATA SSD performance, on either SATA2 or SATA3. I'm sure things are even quicker with PCIe storage; perhaps Mr. Canavan can offer some insight, as I believe he has gone (or will soon be going) with PCIe SSD.

On my 2009 MP, I currently have five SSDs running, three connected via native SATA2 and two via a SATA3 PCIe card. Although I haven't benchmarked, they all seem to perform great and I am quite happy with the responsiveness of my system.

[Michael Canavan]

The PCIe solution is IMO the best for any SSD over 400mbs.

The one thing that got mentioned about SSDs in Yosemite is that TRIM is no longer available for random third party SSDs like this one, OWC (Other World Computing) uses SSDs with good garbage collection and writes their own partitioning code for keeping a portion free for garbage collection to happen in. This is why their drives are sold as 480GB instead of 500-512GB, they have a hidden free space allotment. My solution although not as elegant is to partition off a 5-10% section that you do not use, the HD will then use the ultra free space to do efficient garbage collecting apparently. This is a forum advice thing, no guarantees that it's "the way" to do it. I've also been told that unless you write 10GB of data a day for months on end then TRIM or lack of isn't going to be an issue. So for recording studios it's possible that a better solution would be paying Apple for their hard drives or getting the OWC ones.


A quick run down:

mbs = megabytes per second
gbs= Gigibytes per second

3g and 6g are naming conventions roughly equal to 300mbs and 600mbs respectively. No comparison to gbs.

Sata 3 unfortunately got used at different time for 3g and 6g SATA, hence confusion.


So:
SATA HD and Optical Bays in Mac Pro- 300mbs
PCI bus in Mac Pros - 6gbs

SSDs out now in 2.5" SATA form factor - mostly the fastest is 550mbs
M.2 form factor SSDs out now -1100mbs or 1.1gbs!

To compare to a pretty decent 7200 Western Digital hard drive in my mac speed wise, it clocked in at a whopping 92mbs! Like HC Markus points out at three+ times faster than HDs, SSDs in the SATA or optical bays for most people just using the Mac Pro SATA bus is enough. TO me anyway it's not a huge deal to get a SATA to PCIe card and get that extra couple hundred mbs the PCIe buss offers.

[HCMarkus]

The one thing that got mentioned about SSDs in Yosemite is that TRIM is no longer available for random third party SSDs like this one, OWC (Other World Computing) uses SSDs with good garbage collection and writes their own partitioning code for keeping a portion free for garbage collection to happen in. This is why their drives are sold as 480GB instead of 500-512GB, they have a hidden free space allotment. My solution although not as elegant is to partition off a 5-10% section that you do not use, the HD will then use the ultra free space to do efficient garbage collecting apparently. This is a forum advice thing, no guarantees that it's "the way" to do it. I've also been told that unless you write 10GB of data a day for months on end then TRIM or lack of isn't going to be an issue. So for recording studios it's possible that a better solution would be paying Apple for their hard drives or getting the OWC ones.

With all respect, I must add my perspective:

1. Trim IS available for third party SSDs in Yosemite, but kext signing must be disabled. Kext signing is a security feature new to OSX with Yosemite. See this: http://www.cindori.org/trim-enabler-and-yosemite

2. You can Trim third party SSDs by enabling Trim, then running Repair Disk in Apple's Disc Utility. This will not work on the boot drive, so to Trim your boot drive in this way, you must boot from a separate drive. If you want to run Yosemite and not disable kext signing, you can periodically Trim your SSDs by booting into another drive running, say, Mountain Lion or Mavericks with Trim enabled, Trimming all your SSDs via Repair Disk, then booting back into your main Yosemite system drive.

3. OWC drives use SandForce controller chips with no special firmware of which I am aware. Intel is, I believe, the only company using SandForce that has its own custom, validated firmware. SandForce drives use a data compression scheme that allows them to work more efficiently with compressible data (like BWAV and some sample libraries), but they slow down somewhat when used with incompressible data (like some other sample libraries, MP3, video, and other compressed file formats). Because of the compression scheme, SandForce drives tend to maintain a larger spare area. They still benefit from Trim; it just takes them longer to fill up.

4. Unlike magnetic media, where new data can simply overwrite old data, a memory block in an SSD (NAND) must be empty(erased) before it can be written to. But an SSD does not "know" when data has been deleted unless the operating system tells it. That is what Trim does… it alerts the SSD when data is deleted. With Trim enabled, the OS instructs the SSD as to which data on the drive has been deleted, allowing garbage collection to begin working right away by erasing the memory blocks that contain unused data. Trim thus reduces write amplification (old deleted data does not have to be moved around inside the SSD to make room for new data), extending the life of SSDs and speeding its operations.

I can't say that Michael is wrong when he states Trim may not be necessary for some users. Modern SSDs are very robust and will, in most cases, last for many years. I can say that I believe it is a best practice to keep Trim enabled.

[Michael Canavan]

I can't say that Michael is wrong when he states Trim may not be necessary for some users. Modern SSDs are very robust and will, in most cases, last for many years. I can say that I believe it is a best practice to keep Trim enabled.

I would say it's much safer to not hack the kernel. Sure you can disable a feature Apple installed in OS X but as a person who is not privy to the reasons why they decided to protect the kernel further in Yosemite I would think it's a safer bet to not second guess the software engineers in this case.

Garbage collection in modern SSDs is a lot better than it used to be, and does include erasing erased files, that's what it does. TRIM efficiently tells the built in garbage collection what files to erase, it's not like garbage collection doesn't happen because there's erased files that it doesn't know are erased. the degradation of the speed of an SSD is not likely to happen unless you use the entire SSD to 100%, or write massive amounts of data to disk like servers do. Basically the garbage collection can't keep up, and it's process, (take a block of data, examine it, junk the erased data and move the used data to a previosly erased block) slugs down. Older SSDs had worse garbage collection procedures and this would happen very noticeably.

This guy Kent Smith, in the comments after this article is a Seagate employee and explains it better than I ever could. http://www.zdnet.com/article/os-x-yosem ... d-to-know/

From one of his articles... OP means over provisioning.

 Users can increase the OP, but not decrease it
 During initial setup and formatting, allocate a smaller partition (don’t use the full space)
• SSD must be either “Fresh Out of Box” (FOB) or secure erased
 Leave the extra space unallocated
 The SSD controller automatically uses this as
additional dynamic OP

What TRIM does is free up over provisioning (erased space, or possible erasable space) for the garbage collection, as the disk itself wants to write to the free space and junk the unused erased data. It tells the SSD that the space is free etc. All SSDs have some OP built into them, the larger the OP the better, so a 960GB Crucial is using an extra 40GB for garbage collection, and a one terabyte SSD is using less.


Another thing, because of the built in bottleneck on the SATA bus as opposed to the PCIe bus, nobody using a 4-550mbs SSD on a 300mbs bus is going to notice the possible degradation of speed in their SSD.

[HCMarkus]

OWC's self serving sales pitch is what I see in the linked article. All Apple branded (internal) SSDs support Trim, and OSX automatically enables Trim for these drives. Representatives of LSI, the manufacturer of the SandForce controller, have always recommended using Trim.

Trim is Good.

Seagate now owns the SandForce intellectual property. As noted by Seagate rep Kent Smith in his comments at the end of the article:

"TRIM will provide extra free space for Garbage Collection depending upon the unused space of the end user. If an SSD is only filled to 80% capacity, then the extra 20% of remaining space is free to become "dynamic over provisioning." That means the SSD can be much faster with TRIM enabled and if the user does not fill the SSD to full capacity."

But without Trim enabled, the user, like the SSD itself, has no idea how many cells are actually free to be erased and written to. Not filling SSDs to capacity is definitely a good practice. So is enabling Trim, because it allows the SSD to not be filled to capacity.

The Trim issues created by Apple with Yosemite are one of the reasons I have not migrated my studio Mac to this version of OSX. There are other reasons, not the least being I prefer to not be an early adaptor/beta tester. The biggest reason is DP8.07 and Mountain Lion have proven to be a virtually flawless combination, and that makes me and my clients very happy.

By the way, "hacking the kernel" is simply turning off a "feature" that OSX never had before Yosemite. That said, there are definitely pros and cons to enabling Trim under Yosemite. I have furnished a link to Cindori's excellent explanation in a prior post, and encourage anyone interested in this subject to review the information there.

I am hopeful Apple will ultimately allow Trim to be enabled for third party SSDs under Yosemite, as Apple manufactures no Thunderbolt SSD and, as a result, there is no external SSD storage available (other than Apple-branded PCIe storage that can on occasion be found on Ebay) that will natively support Trim under Yosemite.

[mhschmieder]

Useful information, and good explanations.

The reason I'm looking at PCIe is that my regular drive bays are already full, and ready for yet another size upgrade or two as well. I now have close to 6 GB of sample data, between all the drum and orchestral libraries (everything else is tiny in comparison).

I don't know anything about SATA2 or SATA3. My current SSD system drive is in the second optical slot, dangling, since everyone said that's OK with a non-mechanical drive.

Still not sure what to do, so I'll wait for more discussion. I thought OWC'S PCIe w/ eSATA ports was my only realistic option (or for anyone else with a 2010 MacPro as well), and liked how I could then part with my current eSATA PCIe card and free up a slot for more SSD expansion (I use eSATA for my external backup drives).