Sequentially, yes. In day to day tasks, random access tasks? Not a chance.
Depends on filesize. Up to about 128KBytes you're right. At 128K to 512K file sizes the RAID catches up and is relatively the same. With files of or larger than 1MB the RAID0 is actually faster (Random Read and Write). At least that how my drives profile. A 3-drive RAID0 is about the same as the SSD from 64KBytes on and at 1MB trounces the SSD.
Of course the inverse is also true. The breakdown (on my system) is like:
- 512Bytes to 16KBytes: SSD = 100x to 60x (faster than 2-drive RAID0)
- 16KBytes to 128KBytes: SSD = 60x to 2x (faster than 2-drive RAID0)
- 128KByte to 512KByte: SSD = 2x to 1.5x (almost same as 2-drive RAID0)
This is testing against a VERY VERY fast brand new mSATA SSD drive. It probably equalizes a little sooner with the average SSD and sooner yet with one that's been in use for a few months.
The bottom line is all three products (Pure SSD, SSHDs and HDDs) have there target sector.
SSDs: Maximum random access performance for Apps, Caches, Games, OS.
SSHD: Combination of random access performance and capacity in minimum of space.
HDD: Maximum capacity per £/$.
Seems like a reasonable opinion, I can agree with that. )
At the end of the day maximum performance in 99% of tasks is a SSD.
I don't agree with this at all! Not even close. For about 10% of common tasks (10% of your time spent as a user) the SSD will kick butt! For about 75% of common tasks they are the same - even the same between a single HDD and an SSD (no RAID). There's just not any actual noticeable difference most of the time. And of course the remaining 15% of common tasks the SSD usually isn't large enough to even do at all. [and I'm being extremely generous with the 10%... it may actually be more like 0.1%]
If you don't believe me try it. Get a stopwatch, load photoshop, find and locate (with purpose and intent like normal) 5 images to edit and print. Edit them and print them. Do that once for the SSD and once for the HDD. Your times will be relatively the same with sometimes the HDD being faster and sometimes the SSD being faster - just depending if you sipped your coffee or not. It's not like an SSD speeds up your processor or anything.
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Even for boot up, system start, and application start ups (somewhat general tasks) the SSD is
not even 1.5x faster than a 2-drive RAID0.
So yeah using an SSD gives a person a cheap thrill about 3 to 5 times a day for about 5 seconds (each thrill). Past that performance is generally about the same. As human beans capable of noticing change more than detecting that which does not change, we may feel that SSDs are oh so awesome but truth be told you're paying a lot and sacrificing a lot with an SSD which doesn't really do as much as you might want to think.
Whilst SSHDs and HDDs will almost certainly merge, pure SSDs for performance won't dissapear before the next generation of storage tech comes along...
Pure speculation of course.
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My guess will be that SSD, System RAM, and HDD technologies will all merge together within the next 10 years. The entire RAM/Storage subsystem will be a plug-n-play black box about the same as a current SSD but maybe with a fan or something.
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My bet is that SSD drives will be essentially obsolete before that time. They almost are now with the advent of SSHD.
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