boot - Does SSD drive really speed up overall performance of computer?
2014-07
James C
Mostly when I talk to other people or check other discussions on forums, people insist that SSD ( Solid State Drive ) boosts overall computer performance big time.
I however cannot fully understand it. Sure, I believe SSD helps in computer boot and software loading speeds. But after the OS and the software you will be using is loaded, doesn't most of the data exchange happen between CPU and RAM ? How can SSD play a role in speeding up the performance here ? Thank you.
allquixotic
A few things to consider:
- Yes, if you have tons of RAM and most things you do involve reading data from the hard disk (as opposed to writing), you will not experience very much speed-up from an SSD after you are booted and all programs loaded in RAM.
- Most people don't have enough RAM to keep all the data and programs they use loaded in RAM at all times, so it gets paged in and out as people use programs or files, then let them go idle.
- Writes to disk still task the disk subsystem no matter what you do. NTFS, the filesystem on Windows, has an automatic mechanism that forces out all "dirty buffers" (which are pieces of files that haven't finished writing to the actual hard drive) about every 5 to 10 seconds (it may even be configurable in the registry). You can't keep dirty buffers in RAM forever because RAM is volatile; if you lose power, all your dirty buffers are lost to the mists of time and never get written to your disk. Some programs explicitly call a programming function that says "put my data on the non-volatile storage mechanism NOW!" -- which the OS faithfully obeys.
Writes are really what ends up killing the performance of hard disk drives, because of the seeking around to various sectors on disk. Parallel writes are even worse: if the filesystem is trying to handle a large number of requests to write on different parts of the disk, the disk heads constantly have to move around to get to the places they're needed to satisfy the request. By contrast, a "sequential" write can be done very quickly because the hard disk platter is spinning around all the time anyway, so the heads can remain more or less in a fixed position (they still have to move, but not as often).
Well, there's writes, and then there's boot-up and the initial loading of program files off disk. SSDs also do that faster, because, during boot-up, many programs are trying to simultaneously load their files from disk, which creates a "seek hell" similar to how a lot of parallel writes cause the same thing to happen. There are some filesystem tricks you can do to alleviate some of this (you can also load in programs gradually rather than all at once; e.g. delay start services), but you can't completely eliminate the effect without making the boot-up process take much more time.
So in summary:
- During program installation, video capture, photo editing, installing patches and updates, boot-up and shutdown, audio capture/editing, and reading of extremely large files (such as data associated with high-end video games), these situations are poorly-suited to keeping everything just cached in RAM. So no matter how much RAM you have, these situations are going to "stress" the disk subsystem. When the disk subsystem is stressed, and is seeking a lot between different locations on disk, it is much better to have a random access solid state device that can access any location on disk much faster, rather than having to wait for rotating media to come around to the place where it's needed.
- Outside of the above scenarios (that is not an exhaustive list of scenarios, but you get the idea), a system with a large amount of RAM is not going to suffer significantly from performance problems, even if it has a traditional spinning hard disk drive.
You have to evaluate your use-cases and how important boot-up/installation/loading times are to you, compared to the relatively higher cost per gigabyte of SSD storage versus hard disk storage. Also, if you move your unit around a lot (as in a laptop or mobile), hard disks can sustain damage easier than SSDs from shock or motion, so there are clear advantages to SSDs there regardless of other factors.
XHR
I'm going to be building a new system soon and I'm willing to spend a few more dollars to improve my hard drive performance. This will be a general use system so I just want to see HD intensive tasks in general go faster whether it be booting, application loads, game loads, maybe video editing, whatever.
My initial thought was to just buy 2 WD Raptors, RAID-0 them together and then just get a regular 1TB+ 7200 SATA drive for storage. The raptors would be my OS drive and all my installs would go there. I could perform whatever work I feel like on the OS drive and then when done move it over to the storage drive. Thus, its not too big a deal if one of the raptors failed, I would just have to reinstall everything.
Thing is, in reading some reviews, not everyone is impressed or notices speed improvements. This gets me to look at other options and honestly there are so many that it seems almost impossible to know what the best is for a medium price range.
SSD's have crazy differences in speeds between manufacturers and models, in the hundreds of Mbps! They also scare me right now, various reports of weird behavior like application freezes and such. I think I've actually experienced this on my SSD Eee netbook, though I can't confirm its the SSD's fault. Maybe the more expensive models don't have this issue. SAS 15k drives are comparable to the raptor's in cost and have better performance but it looks like a decent controller card will run you 200-300 easy.
Honestly right now I'm considering just getting a couple 1-1.5TB standard 7200 drives and raid-0 them together. It would be a huge waste of space as I have no use for that much room for an OS drive but it actually seems like a decent idea as I can probably do that for under $200 and still get a performance boost. Would it be slower than a single raptor (price is about the same at this point), hard to know really unless someone does a side by side comparison. People have done reviews I know but they get outdated fast as speeds and cache sizes improve on a regular basis.
I guess a 100% certain answer to the best combination for your money is pretty much impossible as nearly every combination out there amongst various models and types would need to be evaluated. So I guess I really would just like to get some insight into what generally will be a performance boosting setup for a mid range price (200-500). Thanks.
user10762
I have never found raid arrays really make that much of a positive performance boost for every day use. They certainly don't improve access times and that is what you tend to notice most in general use. I would also avoid raid-0 unless you don't care about the data being stored.
An SSD is the way to go to get a noticeable speed boost. Use a modest sized (60-128GB) one for a boot drive and a larger mechanical drive for bulk storage. If you want your games to load faster they should be kept on the SSD in which case you might want to get a larger drive (120GB+).
Almost any fairly recent SSD should be OK but Intel is best followed by drives based on Samsung or Indilinx controllers (Samsung are probably safer and Indilinx slightly faster). Cheaper drives based on JMicron controllers are OK only if you are on a very tight budget. If the price is cheap and there is no mention of the controller then assume it is JMicron based regardless of how impressive the specs might seem.
John T
The Intel X-25M fits well into your budget and has had great reviews. Even Linus Torvalds has been impressed with his Intel SSD. The X-25E performs better but only provides 32GB space, at a fairly higher price. If you choose a SSD, I'd only keep the OS on it and programs you use frequently that require high data transfer speeds. Other programs can be installed to a seperate 7200rpm disk.
check out tomshardware hard drive benchmarks. they benchmark all kinds of different drives from 3.5" to SSDs. There is also price included beside each one.