Are the RE3 / ES.2 versions worth the price diff? (added 2nd Q!)

Discussion in 'Mac Pro' started by Loa, May 26, 2009.

  1. Loa macrumors 65816

    Loa

    Joined:
    May 5, 2003
    Location:
    Québec
    #1
    Hello,

    Quick question that seems to have a simple answer: are the "raid / enterprise" versions of HD worth the price difference?

    I'm planning on buying 3 500Gig drives soon to use as a RAID0 in my mac pro. I also remember reading (don't know where) that for domestic use, i.e. not 24/7, the raid versions where not necessary.

    Can someone here confirm/deny that idea? (Or point me to a relevant discussion...)

    Thanks

    Loa
     
  2. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #2
    In a RAID setup, YES. You get an order of magnitude in UBE (Unrecoverable Bit Error) rates. 1E15 on these, vs. 1E14 on most consumer models. It can make a difference.

    But with any RAID array, you really need to have a backup system in place. So please don't think you don't need it. Especially with RAID 0, as you lose all the data in the event of a failure. You'd have to fix the problem, and restore from the backup(s).
     
  3. Loa thread starter macrumors 65816

    Loa

    Joined:
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    Location:
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    #3
    Hello,

    Thanks for the answer. The reason why I'm building a 3disk RAID0 set is to have the 4th disk as back-up. When I'll have my complete set-up (i.e. when I'll have the money to buy everything!), there will be a SSD as boot in the second optical bay, 3disks in RAID0, an internal back-up and external back-up.

    I think it will get me covered! In 15 years using macs, I've only had 2 HD dying on me. So with 2 back-ups, I should be alright... :)

    Loa
     
  4. dagomike macrumors 65816

    Joined:
    Jun 22, 2007
    #4
    I think the simple fact these drives are designed to run a lot longer is a plus. Doesn't mean you'll never have a dud, but on average they should perform more reliably. So, on one hand you could save the money and buy a drive if/when a regular model dies, or just spend the money up front and be less likely to deal with the hassle. I go for the later because dealing with a recovery, particularly one that might be a slow death, is a real pain in the ass. Whatever you do though, be sure to back up.
     
  5. Loa thread starter macrumors 65816

    Loa

    Joined:
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    Location:
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    #5
    Hello,

    Additional question: The price difference between a re3/ES2 model with 16mb or 32mb cache is enormous!

    I've read somewhere that for drives used normally (non-RAID), the 16/32 difference didn't result in significant speed benefits.

    Is this the case for RAIDs?

    Thanks

    Loa
     
  6. Tesselator macrumors 601

    Tesselator

    Joined:
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    Location:
    Japan
    #6

    Yes, (I mean no!) It's more true for RAIDs as the cache is combined. 32MB x 4 HDDs for example is 128MB of cache. So lets say you were in an image editing app that saved on a timed interval and you had ten 5MB images open. When the timer went off they would all save almost instantly.

    But if you want RAID class drives on the cheap might I recommend the Samsung HD154UI drives? They're about the same speed as the WD Black drives you hear so much about, their UBE rating is 1E15, they're 1.5 TB in size, they're cheap, they're low power consumption so you'll save another $25 or $50 annually, they come with a 5-year warrantee, and because they're low power they run cooler even though they're rated at a whopping 65c MOT. I'm running 3 of them in a RAID 0 and they're very fast!

    http://forums.macrumors.com/showthread.php?t=707152

    They're 32MB Cache too BTW: http://www.samsung.com/global/busin...=72&type=61&subtype=78&model_cd=441&ppmi=1170 You should be able to pick them up for about $120 US street - $100 in Japan :D.
     
  7. nanofrog macrumors G4

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    May 6, 2008
    #7
    The RE's are a newer design than the ES.2's, and are faster.

    Cache can make a difference with RAID. Not just the drive cache, but what is built in to the hardware controller, if that's the route taken. A few have the ability to upgrade it via DIMM slot of some sort (SODIMM in some cases).

    It would definitely help in software based RAID. Between these two families, you'd be better off with the RE3's IMO. :)
     
  8. Loa thread starter macrumors 65816

    Loa

    Joined:
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    #8
    Hello you two!

    Thx for the info. The price difference for RE3s with 16 and 32 megs is 1:2. Is that extra 16mb worth twice the price?

    And Tess, in Canada I could only find one seller with the drives you suggested, in special order, for 170$ Cnd. Also, since I'm now planning a 4 drive RAID0, 6TB would be simply ridiculous. Granted I would only have data on the very fastest parts of the drives, but still...

    I can have the RE3 500GB drives for about 90$ Cnd, so it would make the cost of my RAID go from ~360$ to ~700$. A bit steep. For that price difference I'll buy 8GB of ram, a rack to mount two HD in the 2nd optical bay and have cash to spare.

    Loa
     
  9. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #9
    What are the exact models and prices you're looking at?

    BTW, until now, I hadn't realized your were located in Canada. :eek: :p
     
  10. dr. shdw macrumors 6502a

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    Aug 27, 2008
    #10
    Are you shooting for space or speed? If speed, maybe go SSD.. ;)
     
  11. Mac Husky macrumors regular

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    Mar 28, 2009
    Location:
    Bavaria, Germany
    #11
    If you don´t need the space that Tess is having with his new Samsung EcoGreen F2 1.5 TB (price Germany: € 107 = USD 150) you can of course go for smaller RE3 drives from WD for much(!) less - e.g. WD RE3 320GB (price Germany: € 52 = USD 73). Going for bigger RE3 drives from WD the Samsung is the cheeper solution. It depends on your needed space. And don´t forget, that you have to backup all that stuff from the RAID0 - what is kind a lot having 1.5 TB each in a RAID0 with 4 of them ;)

    I am also thinking about a RAID0 with 3 or 4 disks, as you know. Going with 3 or 4 RE3 320GB would be enough for me, I guess so far. On the other hand I am thinking about not going with a RAIDO at all. To test both and stay with no RAID0 at least the mentioned Samsung would be a very good idea. Because not going for a RAID0 when tested, the WD RE3 is to small for other use in the system. I could use the Samsung much better then.

    So my plan is to buy some of the Samsungs and try it with and without a RAID0. If I should turn not to proceede a RAID0 after testing, I might use them for the Mac Pro also. So I don´t waste money by testing. If I should like the speed of the RAID0 and making friends with the backup solution of it, I tend to go for some smaller RE3 and put the Samsung drives in my new coming NAS.
     
  12. Loa thread starter macrumors 65816

    Loa

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    #12
    Hello,

    I'm looking at the 500GB models.

    Right now I have my OS and all my data on a 640GB HD, with 250GB left unused. Sure I have a few TBs of movies/tv series/documentaries burned on DVDs, but having all these on my RAID would really be pointless.

    So four 500GB drives would mean ~2TB of data, or ~1TB of data at "high speed", which is plenty.

    Dr.Shdw: As for the SSDs: I'm thinking about it, as Nanofrog and Tesselator know from previous discussions. But my plan right now is to boost my ram to 8GB and set up a 4 drive RAID0. I'm going to place 2 of those drives in the 2nd optical bay, the remaining 2 in the standard HD bays, have room for a 1TB back-up drive and an open slot for a SSD if I eventually go there. (And finally, that 640GB drive will be an external back-up I can take with me in case of emergency.)

    Husky: even with 6TB, I could not even begin to imagine how I would fill them. So I would not need to back up all 6 of those TBs! :-D

    Loa

    P.S. I've opened up my optical bay to be able to see what I need to fit 2 HD in there. I found noise suppressing brackets at OWC, but I still can't find the Y-cable. Can anyone point me in the right direction?
     
  13. dr. shdw macrumors 6502a

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    Aug 27, 2008
    #13
    How old is your Mac Pro? Having 1 good SSD is like having the speed of 12 15k SAS drives RAIDed. :)
     
  14. techathy macrumors newbie

    Joined:
    May 3, 2009
    #14
    Enterprise class drives, Barracuda ES line, WD RE series, UltraStars etc. are generally more robust than the desktop counterparts. I've seen this not only in RAID arrays/server storage but also in general desktop usage for 24/7 machines.

    After using Seagate and WD desktop drives with limited lifespans in G5 towers on 24/7 I'm now using WD RE2 & RE3s without any problems.
     
  15. Loa thread starter macrumors 65816

    Loa

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    Québec
    #15
    Well not quite: that's the problem with SSDs... People tend to overestimate the speeds because of all the hype.

    Intel's X25 M 80GB SSD = 260MB reads, 80MB writes. (~350$)
    Intel's X25 E 64GB SSD = 250MB reads, 200MB writes (~800$) (Yes, that really is 800$)
    OCZ Vertex 120GB SSD = 265MB reads, 193MB writes (~300$)

    As a point of comparison, Tesselator created a 3 drive RAID0 of Samsung's new 1.5TB EcoGreen drives, and the lowest speeds he got was around 550MB/s reads and 150MB/sec writes. (Best case has much higher write speeds.)

    It cost him ~300$ and got 4.5TB of storage. And that was only a 3 drive RAID0, using fast drives, but not 15K SAS drives!!!

    Sure the SSDs have 0ms seeking times, and that will be helpful if you have to read thousands of small files (like an OS drive).

    So as I said I'm thinking about a SSD as my OS drive one day in the future, but I'll wait and see how a 4 drive RAID0 will perform.

    Loa
     
  16. dr. shdw macrumors 6502a

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    #16
    Look up 4k Random Read/Write benchmarks..
     
  17. Loa thread starter macrumors 65816

    Loa

    Joined:
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    Location:
    Québec
    #17
    That's exactly my point.

    For a lot of small files, a SSD is good. But NOT out of this world. But what else beside a system folder has a lot of very very small files???

    I work with PS, with files between 50mb-500mb. People working with video use files ranging in the GB. The fact that a drive can read/write a lot of 4K files is pretty much useless outside of a OS drive.

    And even for a OS, it's not game changing: having PS start in 1 second instead of 10 is all fun, but in the real world it doesn't change a single thing. First off, the second time I launch PS on my regular, non-RAIDed 7200 HD, it loads in 2 seconds. Since we have Macs that are very stable and don't require restarts, almost all my PS launches are "second times".

    Second: sometimes I work on PS for hours at a time. The difference between let's say 2 hours of work or 2 hours and 10 seconds is insignificant.

    ---

    If you're stuck on a laptop, a SSD will make a world of difference, while locking you into a very small capacity. But on a Mac Pro, a RAID will give you equal or better performance while giving you more than enough room...

    I ask again: what's the use of reading 4K files so fast, outside of a OS?

    Loa
     
  18. dr. shdw macrumors 6502a

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    #18
    .1 ms access time helps a lot too
     
  19. Loa thread starter macrumors 65816

    Loa

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    #19
    In theory yes. And the general consensus is that it's 0ms on certain SSDs. But, again, it's only significant if you have to read/write hundreds of very small files.

    How often do you have to read/write hundreds of 4K files? Do you even use 4K files? I certainly don't (outside of my OS). The bigger your files are, the less relevant the seek time is. It's not negligible, but it's not game changing either.

    I was very "sold" to the SSD concept until I asked questions on this forum and read their limitations in good articles all over the web.

    In a couple of years we'll probably all use SSDs. But right now, even without considering the major price/GB and maximum size limitations, there are other factors to consider: there are still some bugs to squash (particularly when using them with Mac systems) and some fundamental issues to resolve (like speed degradation with usage).

    Don't get me wrong: SSDs are very interesting, but IMO they're just not there yet as HD replacements except as very expensive boot drives.

    Loa
     
  20. dr. shdw macrumors 6502a

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    Aug 27, 2008
    #20
    HFS+ handles SSDs pretty well..and I haven't had any problems on my MBPs/MPs. Also speed degradation is fixed with TRIM support. HDs degrade in speed too..

    Even opening multiple large files at once off a SSD will be faster than your potential RAID setup.
     
  21. Loa thread starter macrumors 65816

    Loa

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    Québec
    #21
    Go and read OCZ's Mac forums to support their SSDs, and read up on the problems the Intels had on Macs before the latest firmware.

    Lucky for you, but it'S not the general case.

    "will" be fixed with TRIM support, which OS X still doesn't have to my knowledge.

    As for better speeds, the numbers are well known and quite public.

    Give me your numbers, tell me how you tested this, and how many times.

    I'd be quite happy to be shown that 1 SSD is faster than your 12, 15K SAS RAID0. But show me your numbers first. Without them, you're just feeding into the hype.

    Loa
     
  22. dr. shdw macrumors 6502a

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    #22
    No problems with sleep or anything..the ones of the forum were the exception.

    The speed degradation is minimal.

    http://www.hardforum.com/showthread.php?t=1409482
     
  23. Loa thread starter macrumors 65816

    Loa

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    Québec
    #23
    Hello,

    All good info, and relevant too. I never said that SSDs were useless, just that they're not ready for prime time IMO.

    And I'm till waiting on your numbers for this.

    And for you to compare 1 SSD vs 12 15K SAS RAID0. One of the guy in the forum thread you linked said he replaced 7 of those 15K SAS with 4 SSDs.

    Loa
     
  24. dr. shdw macrumors 6502a

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    #24
    Workstation bench. http://www.tomshardware.com/reviews/intel-x25-e-ssd,2158-5.html
     
  25. Loa thread starter macrumors 65816

    Loa

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    #25
    All the tests on that page (and the following one) repeat exactly what I've been saying since we started this conversation.

    These tests represent SSDs against each other and one very fast HD. Of "course" the SSDs will be faster than the single HD! (Although the HD beats them in one test!)

    I've been talking about a 3+ RAID0 setup.

    Where are your results man: one SSD vs twelve 15K SAS RAID0???

    Loa
     

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