MacBook Pro Processing Bandwidth Reality Check

Re: MacBook Pro Processing Bandwidth Reality Check

I installed my new SSD drive this morning. It feels like a new machine.

Just beware in Mac OSX TRIM is only supported on Apple SSD's without tweaking. Hopefully you bought your SSD from a Mac retailer that sold you an SSD based on SandForce controllers that does garbage collection without the need for TRIM. If not, as soon as you have written enough bytes equal to the capacity of your drive you are going to hit a performance wall on writes that will make you wish you had your old hard drive back.

This is due to the way flash memory works and the fact that before a cell can be written to, it has to be erased. Flash memory cells are quite large compared to individual bits on a traditional hard drive so if the cell isn't completely empty before data needs to be written to it the entire cell has to be read and buffered, the cell erased, then the old data written back along with the new data.

That's why you hear the term garbage collection and where either TRIM or over-provisioning come into play. With TRIM the OS tells the drive what data is good or not, and the drive shuffles bits in the background to always ensure there are at least a few completely empty flash cells standing by for maximum performance. With the SandForce based SSD's, they have extra capacity and shuffle bits without regard to whether the data is "good" or not using the extra capacity to always ensure there are completely empty flash memory cells available for writing.

Given this dynamic of SSD's and even with TRIM or other garbage collection, for recording audio I would still highly recommend a firewire external drive of the traditional magnetic spinning disk variety. Firewire over USB because Firewire is not near as CPU dependent (it can work independent of the CPU) and it has much lower latency; both things that will help you dramatically when recording audio.

SSD's are great for many things, but I wouldn't recommend them for recording audio to. They are definitely not a drop in replacement for traditional hard drives in all circumstances.
 
Re: MacBook Pro Processing Bandwidth Reality Check

Just beware in Mac OSX TRIM is only supported on Apple SSD's without tweaking. Hopefully you bought your SSD from a Mac retailer that sold you an SSD based on SandForce controllers that does garbage collection without the need for TRIM. If not, as soon as you have written enough bytes equal to the capacity of your drive you are going to hit a performance wall on writes that will make you wish you had your old hard drive back.

Well... bugger... :(

I was intending to buy one from OWC/MacSales (I've bought a couple from there before for other people) but their 6G range isn't compatible with my 2010 MBP (it says they'll only run as SATA 1.0, not SATA 2.0) and their 3G range was out of stock for three weeks, so I ended my getting an OCZ Vertex Plus R2 240GB from Amazon, which is *not* a Sandforce-based model. It did have plenty of good reviews on their from Mac users, so I figured I was safe enough, but maybe they just haven't hit the problem yet. I remember reading about the whole TRIM business before, too, and completely forgot about it... :(

Doubly annoying, because I have also since concluded that I'm probably going to have to use a bigger external drive for the recordings anyway, because I'm not going to be around for some of the shows they want to record, and I'd rather just make it simple for the (teenage) operators and just let them record as much as they want and then I'll sort through it later, rather than them having to copy stuff off and delete it every 2-3 shows (not enough free space on the SSD for more than that) and deleting the wrong thing.

I have a couple of external FW800 drives, so I guess I'll use one of those... (sigh)
 
Re: MacBook Pro Processing Bandwidth Reality Check

I ended my getting an OCZ Vertex Plus R2 240GB from Amazon, which is *not* a Sandforce-based model. It did have plenty of good reviews on their from Mac users, so I figured I was safe enough, but maybe they just haven't hit the problem yet.

How fast you hit the proverbial wall depends on how full the drive is and how much they write to it. It only becomes blatantly obvious when there are no totally empty flash cells available for writing to. And it may do background garbage collection, I think some of the Marvel controllers did. Looks like it uses OCZ's in-house Indilinx controller and in the spec sheet they have garbage collection listed seperately from TRIM so who knows.
 
Re: MacBook Pro Processing Bandwidth Reality Check

How fast you hit the proverbial wall depends on how full the drive is and how much they write to it. It only becomes blatantly obvious when there are no totally empty flash cells available for writing to. And it may do background garbage collection, I think some of the Marvel controllers did. Looks like it uses OCZ's in-house Indilinx controller and in the spec sheet they have garbage collection listed seperately from TRIM so who knows.

I installed TRIM Enabler, so we'll see how it goes. Thanks again for the heads-up.