My OWC SSD 6G 240GB was about $450
Yes, it is expensive but best money spend on speed upgrading your system!
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SSD vs. HDD
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My OWC SSD 6G 240GB was about $450
Yes, it is expensive but best money spend on speed upgrading your system!
Hybrid Drive
FWIW--I put a 500GB Seagate Momentus XT (retail, .26 FW) in my MBP; boot time averages around 17secs. I know this has gotten some iffy reviews, but mine is quiet, no vibration and FAST. I've been happy with the compromise.
FWIW--I put a 500GB Seagate Momentus XT (retail, .26 FW) in my MBP; boot time averages around 17secs. I know this has gotten some iffy reviews, but mine is quiet, no vibration and FAST. I've been happy with the compromise.
People that claim these low boot times are counting from the time they hear the startup "bong". If you are counting from pressing the power button to desktop, then I haven't seen anyone faster than around 17sec. My MacBook Pro with a Vertex III takes about 18sec, anybody who claims a speed much lower than that is either lying or counting from the startup sound.
I didn't read over every post in this thread yet, but the ones I have so far didn't mention a critical issue with SSDs and Lion: The Recovery Partition.
SSDs have very limited space, the majority of which are 120 GB or less due to consumer costs. That said, the 5GB or so required for the "recovery partition" permanently eats up valuable space on an SSD, which brings the available number of cells to write to down significantly. The less available cells for write operations you have (remember that 5ish GB is gone for good unless you wipe and downgrade to Snow Leopard) means you'll hit that dreaded SSD slowdown wall much sooner than you normally would.
The "slowdown wall" is this: When you write data to an SSD, the data gets written only to cells that have no data in them at all. Once a cell is filled with any data, fully or even partially, it is no longer a valid cell to write new data to. It's an "all or nothing" write. So if you write say a measly 4k to a 512k cell, you've effectively locked out the remaining 508k of space because that particular cell cannot be written to again without first being erased completely.
Compound this by the literally hundreds of thousands of files the OS deposits (especially if you need to install XCode, a must for power users that use MacPorts, Fink, or any X11 interfaces) and you have scads of cells that already just at the end of a fresh install have wasted space. Now add that 5 GB to it. As you write new files or update old ones, the cells that contain the old files are NOT updated. The new/changed data is written to cells that are currently 100% unused. The old cells still contain the old data, but are marked "unused" by the controller even though they still have data in them.
Over time, the available number of completely unused cells drops dramatically, and eventually you end up with all cells written to at one point or another. Once you reach that point, in order to do any further writes, the SSD must first delete a full cell (even if it contains only a miniscule amount of data) and then write the new data to that cell. This brings your once fast SSD to its knees, making it slower than even a regular 5400 RPM HD.
And on top of that, you get fresh salt in the wound in the fact that every time a cell undergoes a write cycle, its lifespan is shortened. Cells have a finite (roughly 10,000) number of write cycles before they can no longer be written to and are only good for read operations.
Many SSDs are "overprovisioned" so that once the "available" cells are all used, the SSDs use spare cells (hard locked and unavailable to the user directly) until all physical cells on the SSD are written to and you end up with the above scenario.
So that 5 GB partition might not seem like a lot to you, but given both the small size of SSDs and the fact that even a tiny 4k text file takes up an entire cell even if the rest of the cell is blank, the damage adds up quickly (and I haven't even factored in swap files which are a full 80 MB each).
Lion makes the user lose both lifespan and space on SSDs where both are at a premium, for something that in all honesty could be just as viable on a physical DVD inserted into an optical drive. There is no opt-out for SSD users.
This is something you'll want to take into consideration when using Lion on an SSD smaller than 120 GB.
SSDs have very limited space, the majority of which are 120 GB or less due to consumer costs. That said, the 5GB or so required for the "recovery partition" permanently eats up valuable space on an SSD, which brings the available number of cells to write to down significantly. The less available cells for write operations you have (remember that 5ish GB is gone for good unless you wipe and downgrade to Snow Leopard) means you'll hit that dreaded SSD slowdown wall much sooner than you normally would.
The "slowdown wall" is this: When you write data to an SSD, the data gets written only to cells that have no data in them at all. Once a cell is filled with any data, fully or even partially, it is no longer a valid cell to write new data to. It's an "all or nothing" write. So if you write say a measly 4k to a 512k cell, you've effectively locked out the remaining 508k of space because that particular cell cannot be written to again without first being erased completely.
Compound this by the literally hundreds of thousands of files the OS deposits (especially if you need to install XCode, a must for power users that use MacPorts, Fink, or any X11 interfaces) and you have scads of cells that already just at the end of a fresh install have wasted space. Now add that 5 GB to it. As you write new files or update old ones, the cells that contain the old files are NOT updated. The new/changed data is written to cells that are currently 100% unused. The old cells still contain the old data, but are marked "unused" by the controller even though they still have data in them.
Over time, the available number of completely unused cells drops dramatically, and eventually you end up with all cells written to at one point or another. Once you reach that point, in order to do any further writes, the SSD must first delete a full cell (even if it contains only a miniscule amount of data) and then write the new data to that cell. This brings your once fast SSD to its knees, making it slower than even a regular 5400 RPM HD.
And on top of that, you get fresh salt in the wound in the fact that every time a cell undergoes a write cycle, its lifespan is shortened. Cells have a finite (roughly 10,000) number of write cycles before they can no longer be written to and are only good for read operations.
Many SSDs are "overprovisioned" so that once the "available" cells are all used, the SSDs use spare cells (hard locked and unavailable to the user directly) until all physical cells on the SSD are written to and you end up with the above scenario.
So that 5 GB partition might not seem like a lot to you, but given both the small size of SSDs and the fact that even a tiny 4k text file takes up an entire cell even if the rest of the cell is blank, the damage adds up quickly (and I haven't even factored in swap files which are a full 80 MB each).
Lion makes the user lose both lifespan and space on SSDs where both are at a premium, for something that in all honesty could be just as viable on a physical DVD inserted into an optical drive. There is no opt-out for SSD users.
This is something you'll want to take into consideration when using Lion on an SSD smaller than 120 GB.
Nice. I used to have this. It vibrated like hell in my 2011 MBP (13"). I could deal with it, so I returned it. Maybe the .26 FW helped with it. It was faster than HDD, but not faster than a SSD though. Its kind of in the middle, but I did see a difference between the HDD and XT though.
Does the "slowdown wall" only occur if the SSD is full? I have a 120 gb Vertex 3 and I plan on always keeping about 20 gb free. What if I fill the drive but then delete 20 gb? Does the drive become slower than a HDD because it's writing over data? I know there's a TRIM hack floating around, but I've read it causes more issues than it solves.
Of course, couldn't think what it stood for (GC)
The vertex 2 has GC and I've enabled TRIM using the Trim enabler patch - so not much more I can do to speed things up, I think?
The vertex 2 has GC and I've enabled TRIM using the Trim enabler patch - so not much more I can do to speed things up, I think?
If your SSD has a special garbage collection and does NOT natively support TRIM (there are some out there like this), DO NOT enable TRIM. Doing so slows down the SSD significantly, often by about 25-30% overall.
Just "deleting" 20 GB does not make those cells unused again. Remember, as I noted in my post, those cells retain the data in them until you either format the drive (low level "zero all data" format) or you write to those cells again.
So let's say you fill up the drive to 115 GB of 120 GB normally without ever deleting a file (best case scenario, will never happen, but using it for simplicity's sake). That leaves you with 5 GB left over that has never been touched. Now let's say you fill up that 5 GB. That means that every cell in the drive has been written to and has data in it.
Now let's say you delete 10 GB of files. The OS sees 10 GB free, but the SSD controller knows better - the cells that contained those 10 GB of files still contain the file data. They are not wiped clean **(see exception below). So even though you may think you've got 10 GB free, you really don't, and any time the SSD performs writes, those cells must first be erased, and then written to again. That's what causes the "slowdown wall".
*** TRIM and "wear leveling" garbage collection routines used by modern SSDs diminish, but do not eliminate the effects of cells retaining data. The reason they diminish the effects is because data in "unused" cells is periodically cleared out, but there's a catch. The catch is what causes the "but does not eliiminiate" part of the last statement. You see TRIM/garbage collection routines require the SSD to be inactive for a period of time (sometimes as long as 30 minutes) before the algorithms kick in and start erasing unused cells and reformatting them to a "zero state" (ready for writes at full speed). If for any reasno the SSD performs writes before that inactivity timer reaches its minimum necessary for TRIM/GC to kick in, the timer gets reset and the cells remain un-erased, and thus still contain data and are subject to the slowdown wall effect caused by the need to first erase the cell before it cen be written to again.
SD/MicroSD type cards also suffer from this, only in their case there is NO garbage collection at all. They're just chips and the host device is the controller. So they truly slow to a crawl once filled unless you either backup and wipe them, or do what is called a "clean sweep" erase of unused cells, which erases "free" cells back to their zero state manually. If you've ever wondered why a phone is "Preparing SD Card" whenever it starts up, it is because it is the host device and must scan the SD card to see what cells are used and which are truly free to write to. It stores that info in its RAM until shut down, and must perform the scan at every startup or whenever an SD card is unmounted and remounted.
Been running Lion on two RAIDed OCZ SSD's for a week now. Stripped RAID. Don't get me started about RAID issues with Lion. But long story short - it rocks. I thought it was fast in SL, but Lion really moves. Once you move to SSDs you'll never go back.
I have a OWC 240 SSD. Great performance! And a 750 GB 7200 HDD in a second bay in one of my MBP 17, i7. They are both formatted Mac OS Extended (Journaled). When I try to turn on FileVault I get an error saying that FileVault can not be turned on on this SSD, it should be reformatted. Any Ideas? is that an SSD problem. I have 147 GB free on that drive...
Any help would be appreciated.
P.S. Sorry I do not want to hijack this threat, just thought it would fit in here good since most readers are using SSD here....
Any help would be appreciated.
P.S. Sorry I do not want to hijack this threat, just thought it would fit in here good since most readers are using SSD here....
Exactly. The difference is night and day. I need more storage than my 160GB SSD can offer, so I installed the SSD in place of my SuperDrive, and put in a hard drive in the normal hard drive bay as a storage drive for my documents, pictures, and music. Works great. The machine is LIGHTNING fast, and finally I can use the SuperDrive bay for something useful! That solution fixed the price and the capacity issue all in one, since I have a small SSD.
Yep - as the reason I stripped two 240GB SSDs for a nice big 480GB drive. This is in my Mac Pro with the other two drive bays accommodating two 2 TB drives.
The system just rocks.
I've always dreamed about having SSDs in RAID. Not sure how you'd need that much transfer, but it still sounds awesome nonetheless!!!
A few things - its cheaper than buying one big SSD, and still shows up as one drive. The speed is just so much faster than traditional drives that its hard to even think about going back.
I wholeheartedly agree that SSDs are orders of magnitude faster than HDD's- I'm just not sure the performance gain on RAID 0 would be that big, if any, considering the differentiation is the elimination of seek time and thus the boosting of IOPS, not raw speed (although SSDs do well there too).
There isn't really a significant price advantage to multiple smaller ones, also, you're talking about big bucks when you're doing more than 200GB of SSD storage in the first place. I like the two drive system, as for now, it provides me with the speed I desire for relatively minimal cost and large storage. At the current prices, it would be downright wasteful to have a large iTunes library and photo collection on an SSD. VMs, the OS, and applications, however, benefit hugely from the SSD.
i've been running lion on an intel 510 ssd. it works well except that on about every three reboots, the whole system freezes at the login screen. anyone else seen this? nothing unusual about my system except for the ssd. clean install of GM with developer account. nothing on the developer forums on point.
mid 2010 mbp i7 8gb ram
mid 2010 mbp i7 8gb ram