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Which OS Performs Best With SSDs? 255

Posted by CmdrTaco
from the io-io-it's-off-to-work-we-go dept.
Lucas123 writes "Linux, Vista and Mac OS perform differently with solid state disks. While all of them work well with SSDs, as they write data more efficiently or run fewer applications in the background than XP, surprisingly Windows 2000 appears to be the winner when it comes to performance. However, no OS has yet been optimized to work with SSDs. This lost opportunity is one Microsoft plans to address with Windows 7; Apple, too, is likely to upgrade its platform soon for better SSD performance."
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Which OS Performs Best With SSDs?

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  • They didn't compare anything to Linux, so I just have one question:

    How easy would it be to modify Windows 2000 to be even better? Replace the file systems, alter the way the kernel writes to the drive, etc?

    • Re: (Score:3, Insightful)

      by Malc (1751)

      What is your criteria for a different file system? NTFS is already a very good one for most of the important criteria.

    • Re: (Score:3, Informative)

      by yossarianuk (1402187)
      Linux will have good support SSD support, you can be sure of it as Linus uses it himself, he mentions it in his blog. (he is using an intel SSD drive) http://torvalds-family.blogspot.com/2008/10/so-i-got-one-of-new-intel-ssds.html [blogspot.com]
  • Awful article (Score:5, Insightful)

    by Nick Ives (317) on Thursday December 11, 2008 @12:53PM (#26076617)

    It conflates the results of several independent tests to form the view that XP is somehow best. It also bandies about meaningless numbers like one OS being x% faster than another without giving any hint of the metric.

    Avoid.

    • by nschubach (922175)

      I gave it the quick once over looking for graphs, or the programs they used... I saw neither.

    • Re:Awful article (Score:5, Informative)

      by iYk6 (1425255) on Thursday December 11, 2008 @12:57PM (#26076693)

      Several problems with the article. No mention of metric, as parent said. No mention of what Linux-based OS they used. Choice quotes like the following, "but Linux is 'always faster' than Vista or Mac OS X -- to the tune of 1% to 2% -- because like Windows 2000, 'it never runs anything in the background.'" What do background applications have to do with anything? And both Windows 2000 and all Linux distros run stuff in the background. Even DOS does that.

      To top it off, the article is spread out over 3 pages. Here's the print link: http://www.computerworld.com/action/article.do?command=printArticleBasic&taxonomyName=Storage&articleId=9123140&taxonomyId=19 [computerworld.com]

    • Re: (Score:3, Funny)

      by Anonymous Coward

      This article is 34% more shitty than the average /. article.

    • by adisakp (705706)
      It also says that Mac OS will be able to optimize for SSD in the future better because OSX is a closed OS. (Which IIRC, the exact opposite is true: Windows is closed source and the lower levels of OSX are open source)
  • by timeOday (582209) on Thursday December 11, 2008 @12:53PM (#26076625)
    Filesystems are fundamentally engineered to cope with the high latency of hard drives, so I'd imagine there are a lot of assumptions to unlearn. But what other implications are there for the OS? Since the tradeoffs between RAM and persistent storage are smaller with SSD, maybe the changes should go beyond the filesystem into the virutal memory system?
    • Re: (Score:2, Interesting)

      by MattBD (1157291)
      Isn't LogFS designed specifically for flash memory? At present most flash drives seem to come with FAT, purely because anything can read that, but that's sure as hell not designed for flash. Seeing as portable music players seem to be heading towards using flash memory, they could do with something like that.
    • by drsmithy (35869)

      Filesystems are fundamentally engineered to cope with the high latency of hard drives [...]

      In what ways ?

    • by Yvanhoe (564877)
      I think that one thing we can forget about with SSD is file fragmentation. The contiguity of data will be far less of a problem with the negligible latency times of these new disks.
      What else ? I don't think we will lose the file-tree metaphor as it is a nice way to organize data. Maybe the changes will be at a higher level : making a lot of small files should be more manageable now. Reading and writing 100+ files simultaneously will not be insane anymore so maybe this will create some new good practices.
      • I think that one thing we can forget about with SSD is file fragmentation. The contiguity of data will be far less of a problem with the negligible latency times of these new disks.

        Well, no, actually -- remember how Firefox used to leak memory? A lot of that was actually memory fragmentation. And RAM has exactly as much seek time as an SSD -- that is, none at all.

        It's less of an issue, certainly. You probably don't want to run a defragger nearly as much, maybe not at all. But there's still an advantage -- especially if the block layer is doing wear-leveling for you -- to storing large files in contiguous extents, and packing small files together into a single block.

        • Bad analogy. This is a totally different issue. Memory fragmentation means you leave little gaps in the allocated blocks which are too small to reuse, effectively wasting memory. It has very little impact on performance, aside from the minor effect of spreading the "used" memory a bit more thinly, leading to more page faults during operation. The speed cost is due to needing to make more reads, not due to the fragmentation itself; there is no seek latency (though the larger allocation could lead to more

          • by SanityInAnarchy (655584) <ninja@slaphack.com> on Thursday December 11, 2008 @04:20PM (#26080213) Journal

            Bad analogy. This is a totally different issue. Memory fragmentation means you leave little gaps in the allocated blocks which are too small to reuse, effectively wasting memory.

            Given a sufficient number of small files, this can happen with filesystems, too. Of course, it's usually not as pronounced, as most filesystems won't pack more than one file into a block...

            Keep in mind, the block leveling algorithm will be abstracting the actual disk organization; defragmenting wouldn't accomplish anything on an SSD

            It would, at the very least, consolidate extents.

            I would also say, it's sad that SSDs have block leveling in hardware -- I mostly blame Windows for that.

        • >Well, no, actually -- remember how Firefox used to leak memory? A lot of that was actually memory fragmentation. And RAM has exactly as much seek time as an SSD -- that is, none at all.

          Memory fragmentation's a different issue. Individual memory allocations need to be contiguous, so if you're memory's fragmented into lots of small chunks, each large allocation will need to grab a new chunk.

          Files don't need to be contiguous, so that can't happen. And, since SSD solves the seek time problem, fragmenting

    • by SanityInAnarchy (655584) <ninja@slaphack.com> on Thursday December 11, 2008 @01:53PM (#26077601) Journal

      Well, the article is crap in many ways -- doesn't cite what benchmarks they actually used, just throws around meaningless percentages and outright lies (Linux and Win2k absolutely do run things in the background).

      One of the other little details they left out is which filesystem they used, on any platform. My guess is, they just used the default -- I wonder if they were even aware of alternatives (you can install Win2k on FAT32, if you really want).

      So, to answer your comment, Linux has at least two filesystems that are designed to work directly on solid-state media. Unfortunately, most SSDs pretend to be ATA hard drives, but the point still stands -- Linux has many filesystems. I wonder which one actually performs best on that ATA drive?

  • ...a lost opportunity... Since the market has already hit its peak and it's too late now. And they'll never be able to sell to the 20 people that are using SSDs.
    • by Koiu Lpoi (632570)
      I wonder what you think are in most EEE pcs, then.
    • by tepples (727027)

      And they'll never be able to sell to the 20 people that are using SSDs.

      Then I'm glad to be one of the 20 people who owns at least one SSD-based netbook computer, one SSD-based Wii game console, one SSD-based pocket media player, or one CompactFlash card. (CompactFlash cards are SSDs in a smaller form factor that is signal-compatible with ATA.)

      • by qoncept (599709)
        one SSD-based Wii game console, one SSD-based pocket media player
        And you're going to run a future OS on these that would benefit from optimization for an SSD?

        (CompactFlash cards are SSDs in a smaller form factor that is signal-compatible with ATA.)
        I think that brings up the fact that, in an effort to sell more SSDs today, the manufacturers are really missing the boat on one of the most important aspects of SSDs. Why are they all in the same form factor as existing drives? They could be made so small,
  • Summary FAIL (Score:4, Interesting)

    by Wonko the Sane (25252) * on Thursday December 11, 2008 @12:58PM (#26076703) Journal

    "If you really want to go inside [the OS numbers], Windows 98 was the fastest of all," Far said.

  • by Viol8 (599362) on Thursday December 11, 2008 @12:59PM (#26076727)

    FTA:

    "Linux is "always faster" than Vista or Mac OS X -- to the tune of 1% to 2% -- because like Windows 2000, "it never runs anything in the background."

    I'm sorry , what? Have these people never heard of daemon processes? What the hell are they talking about?
    If this is their level of expertise I think I'd take any tests they do with a whole cellar full of salt.

  • Uhm, what are they talking about? What are the things "running in the background" that are presumably hitting the disk all the time? Why do they believe that Windows 98 somehow magically bypass the wear-levelling built in to the SSDs? Or are they talking about raw flash, not sitting behind a controller?

    I find this a little scary too: Microsoft also plans a certification program for SSDs

    The conspiracy theorist in me see a future with proprietary extensions and requirement for getting certification is to ma

    • by James McP (3700) on Thursday December 11, 2008 @01:13PM (#26076955)
      I find this a little scary too: Microsoft also plans a certification program for SSDs

      TFA: "Microsoft also plans a certification program for SSDs so that the drives properly identify themselves to Windows 7 and prioritize data I/O for the SATA interface. "

      While MS is known for embrace-extend-engulf, this is nothing to panic over. If the drive passes a string that identifies it as an SSD, Win7 (or any other OS) will use different disk control logic than they will for an HDD. All OSes will benefit if there's a clear way of identifying SSDs; MS, Linux, Apple, Sun, IBM, all of 'em. Change the preferred block size, alter garbage management, adjust caching to deal with 1 ms response times, (typically) fast reads,(typically) slow writes, etc.

    • I for one am glad Microsoft is planning on certifying SSD disks. Hopefully that will keep Joe's SSD and Auto Wrecking out of the SSD space. I work in the Microsoft world and from what I've seen most of the really big problems aren't caused by Microsoft but by third party vendors in both the hardware and software space building cheap stuff.

  • Stupid article... (Score:5, Interesting)

    by Cyberax (705495) on Thursday December 11, 2008 @12:59PM (#26076741)

    Have they tuned Linux for SSD? Like setting no-op IO scheduler (which gives about 20% speedup on some workloads)?

    I suspect that Win2000 and Win98 win because they have the most simple (and stupid) IO schedulers. That's a problem for conventional HDDs, but it's an advantage for SSDs.

    Also, they are talking about "Win98 doesn't support wear-levelling technology". But that's incredibly stupid since modern 'disk-like' SSDs do wear-leveling in hardware.

  • by The Man (684) on Thursday December 11, 2008 @01:00PM (#26076749) Homepage

    Since they didn't test Solaris, the test is meaningless. It's the only OS in existence right now with caching and data management features designed specifically to take advantage of flash to improve real-world performance. The submitter's assertion to the contrary is a deliberate lie, an assumption that until Microsoft does something it hasn't been done, or at best sheer ignorance.

    Read up on the ZFS L2ARC and the use of supercap/DRAM/flash subsystems for separate intent logs that make up the hybrid storage pool [acmqueue.org]. There are plenty of white papers and other material out there, and of course you can also read the source code. [opensolaris.org]

    • The submitter's assertion to the contrary is a deliberate lie

      Don't mistake ignorance for malevolence. ;-)

    • You raise valid point, though /me sarcastic pushes me to rather write something like "probably they couldn't boot it on the hardware"...

      Also note that Sun isn't really advertising their OpenSolaris well. Lots of people who use Solaris on daily basis have absolutely no clue about its open source cousin for Intel processors - and heard first about OpenSolaris from me, Linuxoid.

      But it would be really interesting to see whether the Solaris' optimizations bring something or not.

  • by francium de neobie (590783) on Thursday December 11, 2008 @01:01PM (#26076771)
    When I read into the middle, it says,

    According to Far, Mac OS X runs "a little faster than Vista" with an SSD drive, but Linux is "always faster" than Vista or Mac OS X -- to the tune of 1% to 2% -- because like Windows 2000, "it never runs anything in the background."

    Ok, so Linux and Windows 2000 never run anything in the background. My head exploded so I stopped reading.

    • by icydog (923695) on Thursday December 11, 2008 @01:17PM (#26077011) Homepage
      What? Don't you know that Microsoft invented multitasking with Windows XP? Linux and Windows 2000 are incapable of running background processes.
    • Compared to background indexers in Vista and Mac OS X, Linux and Win2k run nothing in background. Even more most indexers I have seen on Linux allow to suspend or schedule the indexing process. On Vista and Mac OS X you can't do that - it is just there doing all the time something with your disk...

      • by Blakey Rat (99501)

        I know a lot of Slashdotters gripe about this, but I really like being able to hit Start (or Command-Space IRC on Mac) and just type "christmas pa" and get all my christmas party information in one list, instantly. I don't really care if it all runs 1% slower at all other times.

      • Re: (Score:2, Insightful)

        by CommandoCody (1154955)
        Funny, Googling "disable spotlight indexing" for Mac OS X turns up plenty of hits. Oh, wait, you can even do it right from the Spotlight Preference Pane. Look at that!
    • by IronChef (164482)

      Just reading that quote in your post made MY head explode. It's so dumb that I think you need to read it in a mirror to be safe.

      Or is that for fighting Medusa? I can't remember.

  • by Trepidity (597) <delirium-slashdo ... g ['kis' in gap]> on Thursday December 11, 2008 @01:01PM (#26076773)

    The article is all over the map, discussing in vague terms everything from boot-up speed to I/O speed to some sort of generic "runs a little faster" that I assume (?) means overall system or app benchmark performance.

    When actual numbers are quoted, they sound somewhere between questionable and boring. The article quotes all sorts of differences in the range of 1% and 2%. Leaving aside the question of what this is a 2% difference in, and whether a difference that small is even consistently measurable outside of sampling error and quirks of their particular setup, does it actually matter? I'm certainly not going to choose an OS based on a 2% difference in SSD performance.

  • A lot of the really small low power laptops use SSD hard drives. Dell's mini's use them. There is a market for these little laptops. Granted these are not for gamers, or engineers. But for email, web surfing, taking notes in class, these things work fine. I have seen a lot of those Dell mini's in the hands of college students. This fall I may see a lot more.

  • Why would I care? (Score:5, Insightful)

    by Trillan (597339) on Thursday December 11, 2008 @01:10PM (#26076891) Homepage Journal

    Even if their methodology was clear.
    Even if their methodology was valid.
    Even if every percentage point was accurate.
    Even if all of their arguments were valid.
    (And none of these are true.)
    Why would I care enough about 5% to let that pick my OS?

    • by TubeSteak (669689)

      Why would I care enough about 5% to let that pick my OS?

      Not all of these studies/articles are written for the benefit of end users.

      Think of it this way: 5% across 10,000 computers.

    • That reminds me of the advice I used to give friends when they asked about buying a faster computer. I told them to not even bother until the processors were twice as fast as what they had. The meaning of a 5% difference in real-world use is, um, meaningless.
  • by CannonballHead (842625) on Thursday December 11, 2008 @01:13PM (#26076945)

    It's not only 'bad' it's weirdly bad.

    According to Far, Mac OS X runs "a little faster than Vista" with an SSD drive, but Linux is "always faster" than Vista or Mac OS X -- to the tune of 1% to 2% -- because like Windows 2000, "it never runs anything in the background."

    Never runs anything in the background? What in the world does that mean? Am I missing something, here, or is this just the wrong terminology to use? Even at the most basic use level, you can "background" an application in Linux with the ampersand ... I'm confused.

    Not to mention that they didn't test Linux... or, presumably, any Unix OS. They basically only tested Apple and Microsoft operating systems. Hm. I actually like Windows on occasion, and I find that pretty stupid. (I also like Linux :) )

    It did have some interesting things to say though, like the block alignment.

  • by NineNine (235196) on Thursday December 11, 2008 @01:14PM (#26076963)

    Obviously, SSD's are in their infancy. NO OS has been even remotely optimized for them yet, I'm sure (except maybe the big hitters, like Solaris). I'd be willing to be my left leg that the next version of every commercial OS (OSX, Windows, Linux*) is optimized for them. This article is irrelevant.

    • SSDs may change before they become very popular. Right now they are cool, but still too expensive and too small to be used in mainstream computers. We've got a few more years before they start to become the sort of thing you see in normal systems. Well in that time they certainly could change. What is true about their performance today may not be then.

    • Obviously, SSD's are in their infancy. NO OS has been even remotely optimized for them yet

      The Wii console has a 512 MB SSD [wiibrew.org], formatted in an SSD-specific file system called SFFS.

  • Wasn't a massive test. Used Swingbench against 170g database. Quad core, 2gig. Disks were 300g 15k fiber, dual pathed. Swingbench seemed to be like 50 users running VERY poor queries, so this was almost 98% reads. Ms response time was between 3-4, cache hits minimal. Added EMC (1) 146g SSD into the disk group. Response time hit .4 to 1 ms response, identical tests.
    • Your success will largely depend on the size of the result sets. SSDs are much better at small, random reads because there is no seek time(they are random access, all bits take the same amount of time to read). However, several benchmarks have shown that on long, sustained reads, higher end hard drives tend to fare better.
  • by flajann (658201) <flajann@lEULERin ... m minus math_god> on Thursday December 11, 2008 @01:19PM (#26077053) Homepage Journal
    This article fails in several respects:
    1. Linux, a very major OS, is not even included in their tests.
    2. A proper test would not have ANYTHING running in the background.
    3. Issues such as how much read and write caching the OS does will affect performance.
    4. Article does not list a performance table or chart -- but perhaps I missed that.
    5. The actual File System used is really at issue here, but the article did not mention anything about File Systems from what I could tell.
    6. Defragging a SSD? Shouldn't need that. And obviously defragging schemes which were written for magnetic hard drives will probably be less than optimal for the SSD anyway.
    7. Article, as far as I could tell, did not cite the benchmarking methodology used.

    Overall, I would state that this article is useless beyond "cocktail gossip." And really, SSD should have a specific FS written to its peculiarities, which would, of course, render the "OS" questions moot.

    • by dave420 (699308)
      Linux is not a "very major OS". I know it is on slashdot, but not in the rest of the world. Any OS that has less than a few percent of the desktop market can not be very major, by definition.
      • by Ash-Fox (726320)

        Outside of the States, Linux is often the 2nd most popular OS behind Windows.

      • Linux is not a "very major OS" [...] that has less than a few percent of the desktop market

        Who said anything about the desktop market? There are plenty of subnotebooks, handhelds, and embedded devices that boot from flash into a Linux-based environment. I would imagine that even servers could benefit from the faster seeks and lower heat dissipation of SSDs for some workloads.

    • by TopSpin (753) *

      Defragging a SSD? Shouldn't need that.

      Is that actually the case? Honest question here as I am not an SSD engineer. Lacking seek or rotational latency any given block of SSD storage should take equal time to read/write. But does that assure that non-contiguous sequential IO (the thing defragging is intended to eliminate) is exactly as efficient as the contiguous case? (Please forgive my elevation of "shouldn't need that" to the "exactly as efficient" standard.)

      It would seem that non-contiguous operations would still involve more IO commands

  • I developed the distinct impression that the author of this article didn't really understand much of what he was writing about, or else dumbed it down so badly that it lost any semblance of accuracy. I'll admit, I'm no expert (not even close), but to me it seemed very inaccurate.

    For example, there's some talk about how Windows boots compared to OSX, and he goes on to claim that the "BIOS does lots of stuff" while Windows is waiting for the hard drive to spin up. Um, does me mean while the BIOS is POSTing?

    • he goes on to claim that the "BIOS does lots of stuff" while Windows is waiting for the hard drive to spin up. Um, does me mean while the BIOS is POSTing? As in, before Windows has anything to do with the boot procedure?

      Perhaps he really meant to say this: If the BIOS didn't need to wait for the boot drive to spin up, it could probably self-test less of the system before handing control to the bootloader and kernel. The kernel would do further self-tests, prefetch modules and other files needed early in the boot process, and start up other hardware, and doing them all at once would save time. I imagine that LinuxBIOS (coreboot set to load Linux) does something like this.

  • SanDisk: Windows Vista not optimized for solid-state drives [cnet.com]

    From TFA . . .

    Speaking during SanDisk's second-quarter earnings conference call, Chairman and Chief Executive Officer Eli Harari said that Windows Vista will present a special challenge for solid-state drive makers. "As soon as you get into Vista applications in notebook and desktop, you start running into very demanding applications because Vista is not optimized for flash memory solid-state disk," he said.

    This is due to Vista's design. "The

  • surprisingly Windows 2000 appears to be the winner when it comes to performance with SSD

    How is it surprising that a decade-old operating system runs faster on modern hardware than modern operating systems bloated with extra features? They should have tested MS-DOS as well, I'd bet they would have a new 'winner'.

    • by RoboRay (735839)

      They did test MS-DOS. The article referred to Win98 results, which were faster than Win2K results, but don't recommend 98 due to it not supporting wear-leveling.

  • by rssrss (686344)

    WIN2K. I resemble that remark. I am still running Win 2K and Office 97, and they still WFM! WooT!

  • >> Microsoft plans to address with Windows 7 and that
    >> Apple is likely to soon upgrade its platform for as well.

    Apple will likely release TWO versions of Mac OS X, before Windows 7 even comes out (and by "comes out" I mean _really_ comes out - SP1, not the beta that they call their final release). Given that Apple ships SSD laptops already, I'll be STUNNED if Snow Leopard doesn't contain SSD optimizations.

  • by zealot (14660) <xzealot54x.yahoo@com> on Thursday December 11, 2008 @02:35PM (#26078325)

    >I'm suspicious of the suggestion that a log-based
    >filesystem will cure all the ills of the limited flash-
    >controller based wear leveling.

    Yeah. Total bull.

    Anybody who thinks the filesystem can do really well has
    bought into the crud from most existing vendors about how
    you have to use those things differently. If you really
    do believe that, you shouldn't touch an SSD with a ten-foot
    pole.

    If the flash vendor talks about "limits" in the wear
    levelling, and how you have to write certain ways, just
    start running away. Don't walk. Run away as fast as you
    can.

    >A question keeps coming up in my mind about what happens
    >when you split an SSD into multiple partitions, and what
    >*you want to happen*. I use separate partitions for root,
    >boot, and var, because I tend to make root and boot
    >read-only.

    Again, if your SSD vendor says "align to 64kB boundaries"
    or anything like that, you really should tell them to go
    away, and you should do what Val said - just get a real
    disk instead. Let them peddle their crap to people who are
    stupider than you, but don't buy their SSD.

    So what you want to happen if you split an SSD into multiple
    partitions is exactly nothing. It shouldn't matter
    one whit. If it does, the SSD is not worth buying. If it is
    so sensitive to access patterns that you can't reasonably
    write your data where you want to, just say "No, thank you".

    Anyway, I have a good SSD now, so I can actually
    give some data:
    - Most flash-based SSD's currently suck.

    I don't have these ones myself, but last week we had the
    yearly kernel summit here in Portland, and a flash
    company that shall remain nameless (but is one of the
    absolute biggest and most recognizable names in flash)
    was selling their snake-oil about how you need to write
    in certain patterns.

    So I called them on it, and called them idiots. Probably
    one reason why I didn't get one of the drives they were
    handing out, but one of the people who did get a drive
    was the Linux block system maintainer. So he ran some
    benchmarks.

    Those things suck. You will never get any decent
    performance of anything but a very specialized filesystem
    out of them, unless you use them as essentially read-only
    devices.

    For a basic 4kB blocksize random write test, the SSD got
    around 10 IOps. That's ten, as in "How many fingers do
    you have?" or as in "That's really pathetic". It means
    that you cannot actually use it as a disk at all, and
    you need some special filesystem to make it worthwhile,
    and certainly means that wear levelling is probably not
    working right.

    (For the math-challenged, 10 IOps at a 4kB blocksize
    means 40kB/s throughput and 100ms+ latencies for those
    things. It also means that even if some operations are
    fast, you can never trust the drive)

    - In contrast, the Intel SSD's are performing exactly as
    advertised.

    I did get one of these, with warnings about how
    if I want to get low-power operation etc I need to make
    sure that disk-initiated power management is enabled etc.

    Whatever. The important thing is that the Intel SSD does
    not care one whit where you write stuff, or how you do
    it. With the same 4kB random write b

  • I'm still using Windows 2000, though I have a (legal) Windows XP SP2 CD on the shelf. Who's your daddy?

  • by calc (1463) on Thursday December 11, 2008 @02:59PM (#26078751)

    I am at the Ubuntu Developer Summit at Google and listened to a talk given by tytso a few days ago. He mentioned that both ext4 and btrfs will support a new ATA command to tell the drive that a particular sector in no longer in use so that it can reuse it for better wear leveling. So it appears Linux will have better support for SSDs in the near future.

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