The 2010 MBP's did not have the SATA III interface yet therefore your computer isn't capable of using even the full potential speed of the 500GB SATA SSD that was installed. But it still should be at least twice the speed of the old HDD.
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Why the Hate for Fusion Drives?
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The 2010 MBP's did not have the SATA III interface yet therefore your computer isn't capable of using even the full potential speed of the 500GB SATA SSD that was installed. But it still should be at least twice the speed of the old HDD.
Is there any benefit to splitting up the fusion drive into two separate partitions? I bought a new Mac Mini and learned it has the motherboard connector to add an ssd, thus turning the 1tb drive into a fusion drive. I bought the connector, and am currently shopping for an 256gb Apple ssd to plug in. From what I read when it comes time to format the drives I'll have the option to create two separate drives or one fusion drive. Which route should I go?
I kind of like the idea of having a main drive (ssd) to run the OS and apps, and a second drive for storage.
I kind of like the idea of having a main drive (ssd) to run the OS and apps, and a second drive for storage.
But its an SSD Drive. Wouldn't that make it faster then regular Hard drive? I didn't know there were different types of SSDs like that.
There are different SSD just like different CPU or ram type...yes they are all faster than HDD
The SSD in the new iMacs are strong, I assume? They say they're supposed to be up to 50% faster then before?
It's not only about lanes, controllers matters, slc/tlc 2d and 3d architetture...many sata SSD don't even saturate the SATA3 and PCIe SSD have different, very different speeds between one and another
You're putting HDD and fusion in the same lot, which is unfair.
Virtually all writes occur on the SSD part of the fusion drive. The data is moved to the HDD afterward during periods of user inactivity.
The weakness of the fusion drive is visible when random reads happen on the HDD. This will not happen for OS files, which always stay on the SSD, or for files that are frequently used.
I explained that part previous in great depth. PCie is x 2 vs SATA 3
But the reason the newer PCie (3.0) SSDs are faster than the older (2.0) ones is lanes. The comment made by "JasonMovieGuy" was WHY the new one is faster than the older one, well he directly mentioned 50% stronger, but i take that as meaning "whys it faster"...
I didn't discount it, i started with "depends on what" but for a 98/2 read/write OS typical type operation, writes in normal operations are cached. If you are doing lots of writes as was hinted at above with the crazy large files (so not typical 2% usage) the cache is quickly saturated as only a % of the hybrid drive is reserved for use as a write buffer. I don't know what the % of the 24GB SSD is reserved, but its in the order of 3GB (it's called a landing zone) I could find out but it really doesn't matter that much - it's small by comparison. I'm also unsure if the LZ size is the same regardless of fusion drive size or if the % ratio to the overall capacity is maintained for larger drives.
You can see the hybrid drive setup by doing diskutil cs list
To test this it's real simple, copy a 3GB file from a USB/NAS drive onto the local drive while monitoring the physical drives throughput with iostat, you'll see the writes against the SSD side of the hybrid drive. Once the copy is completed, leave it for a while, but keep monitoring iostats - you'll see data migration. Then send over another (not the same) piece of data and assuming the cache has not fully emptied, once the LZ becomes full the writes will now be much slower as the cache hasn't had time to free up all the needed space. Now what i cant tell as i don't have the tools on my mac to check is if the SSD part demotes some of the existing LZ data while maintaining writes to SSD or if it seamlessly switches to writing the remaining data to HDD instead.
Caching (or data tiering as its also called) is a workaround to accelerate only high used (hot) files while providing a write buffer - but by definition if you come to do anything different, performance dramatically changes as the data request is no longer being serviced from the SSD. so 12ms access times.
The other part to remember is the hybrid drive is connected via SATA3, so is still only 50% of the speed of PCie.
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You know a lot of business charge, at least, 300% markup on items to stay in business.
If you call a landscaping company to get a rock. Let's say a $30 rock.
When you write the check it's a $90 rock.
100% covers cost
100% covers labor
100% covers profit in order for the business to, well, stay.. in business.
Not every single business does this. Many of them will charge over that. Some charge under, but it is a fair average.
How much does a home cost in materials?
How about water? In my city water is $7.45 per 2,000 gallons.
We have some of if not the cleanest water in the area. If you go buy a gallon of water from the store, you're looking at an average of $1.22. A little over 300% - 350% markup. On water.
Apple isn't really doing much different than any other single company you pay a 300% markup to.
No, they won't be. NVME is an interface specification. SSD is a type of storage device. One can't replace the other because it is apples vs oranges.
Most SSD drives shipping in last gen of Macs already use NVM Express, including those tiny ones in entry Fusion Drives.
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Most likely you are again confusing hybrid drive for fusion, but if you really mean fusion drive, then the SSD in the FD is for sure not connected via SATA3, but via NVM Express PCIe interface.
There is a paradox situation that even the tiny crippled 1TB fusion drive 2015 models had thanks to using NVMe higher peak performance than those who opted for ordinary AHCI PCIe 256/512GB SSD drives or 2/3TB FD.
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The point was existing current SSDs will evolve... being replaced by NVMe devices in the same way SATA became PCie at the host level. It's all NAND at the end of the day, so must be the same right! No...
NVMe will use 3DXP NAND devices, will they still call them SSDs, maybe..
M.2 doesn't look like SATA3,
ACHI vs PCie, for most operations is only going one way when the q depth limit is 1 vs 64k and latency is 6us vs 3us and PCie having true multicore support.
And yes, I was confusing a swap out i did for someone with a 1TB fusion drive - the HDD part (seagate) was replaced with an SSD which is over the SATA bus.
NVMe will use 3DXP NAND devices, will they still call them SSDs, maybe..
M.2 doesn't look like SATA3,
ACHI vs PCie, for most operations is only going one way when the q depth limit is 1 vs 64k and latency is 6us vs 3us and PCie having true multicore support.
And yes, I was confusing a swap out i did for someone with a 1TB fusion drive - the HDD part (seagate) was replaced with an SSD which is over the SATA bus.
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So I actually returned my 1TB fusion drive iMac because the 29gb ssd isn't fast when it's using the slow spinning drive. I'm done with this computer being slower than my 13" macbook pro with an ssd drive (for almost 1/2 of the cost). I decided to just do the i7 upgrade and the 512 ssd. I couldn't believe that that setup will be slower than my 13". I'm just surprised what an negative impact on computer's performance the spinning drives have versus ssd.
Hmm, can you point a source for this that they (the 2017 iMacs) have faster SSDs? I'm curious.
I was assuming because I'm not quite sure. I read on the overview section on Apple.com for the iMacs that the SSD is faster. Maybe I misread?
Nothing in storage is as simple as "just as fast". In fact, I should have stayed out of this whole discussion, it frustrates me so much as a storage professional (in fact, an NAND Flash storage professional working with SSDs and PCIe storage for the last 8.5 years on the vendor side of the equation.
The SSD part of a Fusion drive is the same SSD interface used if that same model was running native SSD. So if it's a newer system, it's NVME (which is a specific access protocol over PCIe). If it's earlier, it's non-NVME PCIe storage, and if it's even earlier, it's a SATA interface (SATA-III or SATA-II depending again on what year and model).
That said, SSDs and NVMe drives tend to have lower performance characteristics at smaller sizes IF ALL OTHER THINGS ARE EQUAL (and they often are not).
So, if I had an NVMe drive that was 512GB, and was based on X number of Flash chips, a smaller 32GB one based on the same chips would have fewer chips and lower performance. But with small M.2 "blade" SSDs, you can't have lots of chips. So they get larger and smaller by varying the capacity PER CHIP (as well as possibly changing the number of chips). So in theory a smaller SSD could have the same raw "instantaneous" performance as a large one of the same design.
Then comes in the harder part. Garbage collection. If you are writing and re-writing over the bulk of a 32GB SSD, it doesn't take long before background processes have to erase large regions (called ERASE BLOCKS) on the NAND chips. These are done in bulk, i.e. whole erase blocks need to be erased, so the partially filled data in those blocks needs to be read, coalesced with other non-garbage, and re-written to prior erased blocks.
SO, it takes LESS work to push a 32GB SSD (such as used with a Fusion Drive) into heavy garbage collection than it does to push a 512GB SSD into heavy garbage collection.
For this reason, if you regularly use and WRITE files greater than 5-10GB in size, a straight up native SSD is the best choice. There are other good reasons to use SSDs as well, but if you are just a modest user of your iMac, specifically you browse, use email, use iTunes and maybe edit small videos generated on your iPhone, then the Fusion Drive is going to work well for you and save you some money.
Since I work with SSDs and PCIe Flash all the time, my next iMac will be SSD, not Fusion. I just can't keep putting money into HDD, it pains me. I have a bunch of HDD in my Synology NAS and it pains me there too! (lol)
Heh. My primary NAS document drive is a 1 TB SSD. I use platter drives for my security camera and for archival stuff, as well as stored audio and video files for playback (not editing). Even though the connection to the NAS is just Gigabit Ethernet, maxing out at maybe 110 Mbps-ish, having the NAS with a 1 TB SSD data drive is big advantage because of the markedly reduced latency.
Also, one of my day-to-day backup drives is my old Samsung 850 EVO 512 GB SSD, but it's not ideal. Since my main iMac drive is nearing 500 GB, backing up to this drive can be a real problem. If I actually try to use the drive after a backup, it can slow to a crawl, with "a crawl" meaning read/write speeds of below 1 MB/s. I'm thinking if I want to use SSD over USB (with no TRIM support), I'll probably have to get a 1-2 TB SSD. 1 TB SSD for backup may work for now.
Any recommendations for SSDs over USB that might be suited for this?
P.S. My current iMac has a 1 TB SSD. My old iMac had a 2 TB HD but it got so slow I actually started using a FireWire 800 SSD with it. That worked for a while but I'd run into the garbage collection issue (as it was that same almost full Samsung 850 EVO). I presume there is no TRIM over Firewire.
How well does macOS support TRIM over Thunderbolt?
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That's definitely garbage collection. The more empty a drive is, the less pressure on garbage collection, the more full it is and with high overwrites, the more garbage collection takes place.
I have heard that some USB drives allow for trim, but don't know the USB chipset required for it. Sorry, I use TB on my late 2012 iMac for external SSD.
You can help alleviate the garbage collection problem on a non-TRIM SSD by creating a permanently empty space (an unused free space or a partition that isn't formatted). Be careful though: If it's not TRIMMED empty to begin with, creating free space that is "dirty" doesn't help you. So you need to somehow ensure that the entire drive is TRIMMED (maybe take it out and use SATA to clean it up, then put it back in the enclosure) and then, for example, create a 1.5TB partition on a 1.92TB SSD. That extra free space will make GC more efficient by allowing it to have lots of free NAND flash to work with at all times.
It works fine, as TB is just a PCIe link to a TB-to-SATA bridge chip that lives in the TB enclosure. So it really looks like a SATA connection to the host.
I don't know how accurate this is, but I have been told that UASP compatible USB docks/enclosures can support TRIM on other OSes, but only in specific circumstances, and there is no support at all on macOS even with UASP support.
I have a UASP dock, but no TRIM with that in macOS.
I don't really care for my MacBook because the times I'd want to use the dock are few. But for my iMac, I'd really like to have TRIM on external SSD. I could get a Thunderbolt dock or enclosure, but it seems we're talking $200 - $300 for that, with last gen transfer rates, vs. $30 for USB 3 with UASP. For that kind of money I can just upsize the SSDs I buy. In fact, that's what I may do. In August I'll probably get a Samsung T5 1 TB drive for backup and various other things.
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Here's my boot drive (TB external enclosure) on my late 2012 iMac. I notices it wasn't running TRIM, and just learned that you must run "trimforce enable" for every new device (or maybe new make/model?)!! Learn something every day.... my older Samsung that I also have hooked up was already TRIM (via trimforce enable).
