Price being no concern what would be better the raid array or the single SSD?
ArchieZer0
I just replaced a RAID 5 with 3 500GB caviar blacks with an OCZ vertex 3 120GB and the SSD wins hands down. Its the best upgrade that I've ever done by far (even beats going from a 5770 to a 580). It's so fast that starting up windows (including typing in my password and login) is at least four times as fast as my POST.
I have a budget SSD and it makes things fly. Linux boots in 5 seconds and has a usable browser in 10. My bios take twice as long. I could only image how much faster a high performance ssd would be.
Also if price is no concern then why not just raid some SSD's?
Also if price is no concern then why not just raid some SSD's?
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I can imagine like an INTEL 510 or Vertex 3
![eek.gif]( "eek.gif")
I have a F60 SATAII with 275 read/write speeds and my PC takes longer to post then it does to get into windows and open firefox lol
I can imagine like an INTEL 510 or Vertex 3
I have 4 10k Savios - and can confirm that even a budget SSD wipes them away, even in RAID0 let alone RAID10.
The SAS drives are sat doing OS/VM duty in my server rather than my workstation. Better value/GB than SSDs (at least when I bought them), but not fast enough to wow you.
The SAS drives are sat doing OS/VM duty in my server rather than my workstation. Better value/GB than SSDs (at least when I bought them), but not fast enough to wow you.
After two hours of continuous writes, a C300 drops to 15ms access time and 2k iops. Now imagine that sucker after a day a two. I'll stick with my spinners, thanks. =)
That being said...4 drives is really not that many, especially if you are concerned about write performance. With hard drives, it's the opposite of SSDs - you want to go with as many small drives as possible. 10 x 36GB / 15k / 2.5" would be a lot more impressive than 4 x 146GB / 10k / 3.5".
The only thing that can really match or exceed a decent sas array in performance is a ram disk.
That being said...4 drives is really not that many, especially if you are concerned about write performance. With hard drives, it's the opposite of SSDs - you want to go with as many small drives as possible. 10 x 36GB / 15k / 2.5" would be a lot more impressive than 4 x 146GB / 10k / 3.5".
The only thing that can really match or exceed a decent sas array in performance is a ram disk.
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See this thread: http://www.xtremesystems.org/forums/showthread.php?t=271063&page=14 After 64 TERABYTES of writes to a 40gb drive, speeds have not dropped at all. Performs just like a brand new drive. (post #335 and 337)
That sounds like a firmware problem, not all SSDs behave this way.
See this thread: http://www.xtremesystems.org/forums/showthread.php?t=271063&page=14 After 64 TERABYTES of writes to a 40gb drive, speeds have not dropped at all. Performs just like a brand new drive. (post #335 and 337)
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And I'm also pretty sure that SSDs are in fact much faster than RAID arrays, and you 'sticking with your spinners' isn't a wise move if you want the best performance...
I'm not sure where you got the degradation statistic from, but I don't think it's correct.
And I'm also pretty sure that SSDs are in fact much faster than RAID arrays, and you 'sticking with your spinners' isn't a wise move if you want the best performance...
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As I plan on proving as soon as I can justify $2k on SSDs.
SSD and RAID are not exclusive...
As I plan on proving as soon as I can justify $2k on SSDs.
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and what would you do with them? Because for 90+% of uses you'd be wasting upwards of $1700...
I plain don't trust storage devices. And striped SSDs is faster than not striped drives, striping yields a bigger drive... I'd only be "wasting" $500, as one of the drives is effectively (not literally) dedicated to parity.
Besides, my raid card is capable of "800 MB/sec RAID 5 reads and exceeds 380 MB/sec RAID 5 writes", so it's not like it'd be slow.
(source http://www.supermicro.cc/Datenblatt/9550SX.pdf)
Besides, my raid card is capable of "800 MB/sec RAID 5 reads and exceeds 380 MB/sec RAID 5 writes", so it's not like it'd be slow.
(source http://www.supermicro.cc/Datenblatt/9550SX.pdf)
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And even with a hardware RAID card you wouldn't want to run RAID5 for your OS - the performance would be lower than with a single drive for most operations.
You'd be wasting the money because you wouldn't be gaining any real-world speed.
And even with a hardware RAID card you wouldn't want to run RAID5 for your OS - the performance would be lower than with a single drive for most operations.
I run only raid 5 in my desktop, and it's definitely not slower than a single drive, but that's probably due to NCQ and the 128MB of cache. It is noticeably slower with the cache off (but why would I run like that?).
The controller also gets me a few other benefits:
I can swap out drives without powering down
I can grow the array by putting in bigger drives, without powering down, or re-installing the OS.
The controller also gets me a few other benefits:
I can swap out drives without powering down
I can grow the array by putting in bigger drives, without powering down, or re-installing the OS.
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RAID5 does tend to be slower than a single drive in the most important factors for an application and OS drive..... random read/write.
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Depends on your performance metric. A SAS array might be good in sequential but a single SSD can destroy SAS arrays in random performance. In fact, an array of SSDs can destroy SAS in sequential as well. The peak sequential read of a SAS HDD is around 200MB/s last I checked. SSDs are hitting 500MB/s reads now.
An SAS array will not be able to keep up to a SSD in database selects.
What controller are you using?
RAID5 does tend to be slower than a single drive in the most important factors for an application and OS drive..... random read/write.
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What are you doing that is do continuous writes/deletes/updates for that period? This is definitely non-typical desktop usage (but I suspect this is some server).
Depends on your performance metric. A SAS array might be good in sequential but a single SSD can destroy SAS arrays in random performance. In fact, an array of SSDs can destroy SAS in sequential as well. The peak sequential read of a SAS HDD is around 200MB/s last I checked. SSDs are hitting 500MB/s reads now.
An SAS array will not be able to keep up to a SSD in database selects.
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"Talos series, a line of Serial Attached SCSI (SAS) SSDs"
What about an array of SAS SSDs vs SATA SSDs?
I would be surprised to see an enterprise setup that doesn't use some form of redundancy, especially for a database setup.
The bus/controller/casing color does not determine the storage medium. We should make that distinction.
http://www.hardwarezone.com/tech-news/view/175705
"Talos series, a line of Serial Attached SCSI (SAS) SSDs"
What about an array of SAS SSDs vs SATA SSDs?
I would be surprised to see an enterprise setup that doesn't use some form of redundancy, especially for a database setup.
The bus/controller/casing color does not determine the storage medium. We should make that distinction.
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