Apple Flash-Booting MacBooks?

[topgun072003]

did you guys read this?

http://www.appleinsider.com/article.php?id=2092

[MacRumors]

http://www.macrumors.com/images/macrumorsthreadlogo.gif (http://www.macrumors.com)

Appleinsider reports (http://www.appleinsider.com/article.php?id=2092) that Intel demonstrated their upcoming NAND flash-based laptops at their Developer Forum:

At the forum, Intel mobility chief Sean Maloney conducted a demonstration in which he booted two PCs, one with 256MB of flash memory, and the other without. The PC with flash booted in about half the time.

The advantages of incorporating Flash-memory into the laptops reportedly include faster booting, wake from sleep, application launching and longer battery life.

According to Appleinsider, Apple has been working with Intel to incorporate NAND flash into next-generation MacBooks sometime in 2007. Before this feature is introduced, however, the rumor site still expects (non-Flash based) MacBook and MacBook Pro revisions before the end of the year.

Rumors of Apple looking into this Flash-caching techology has previously been reported (http://www.macrumors.com/pages/2006/06/20060615153257.shtml) with claims that they may go into an "ultra-portable" laptop by Macworld San Francisco in January, 2007.

[zwida]

Been looking forward to this for years. I know that boot times have come down significantly in the last few years, but instantaneous on from startup would be pretty amazing.

Finally a true "computer appliance?"

Edit: And yeah, bring on the ultra-portable, all-flash laptop.

[hagjohn]

sweet. I figured since Vista has this option.

[GFLPraxis]

What are the advantages of NAND Flash other than booting faster? Is it anywhere near regular RAM in terms of speed?

Is double booting speed worth the price?

[Don't panic]

good news. i had wondered for a while why they don't start using flash memory. with the sizes they have now it should be doable, at least in parallel to regular hard drives, which can act as a internal back up/storage system.

[storage]

good news. i had wondered for a while why they don't start using flash memory. with the sizes they have now it should be doable, at least in parallel to regular hard drives, which can act as a internal back up/storage system.
Because they can only be used for X erase/write cycles.

[PlaceofDis]

interesting implementation, but this is just rumor and the title of this thread treats it as a bit more than that.....

obviously it has some benefits, but will be pricier as well. Apple does have a good place in the flash market now considering how many chips it buys, but does that really matter? no. because apple will be buying the parts from Intel who will be buying the flash chips. :rolleyes:

it will be a great, great day when hard drives in notebooks are flash.
it'll be a long wait though still.

glad to see Intel moving things forward though, hopefully.

[appleguru1]

Very interesting.. but unless we're getting 100+GB flash drives... I'll still want an hdd ;)

though.. it'd be cool to have some non-volitile flash memory to store the OS and other critical components on.

[joshysquashy]

Because they can only be used for X read/write cycles.

so why are they being considered now? what has changed?

[prady16]

What kind of an impact would this have on the total cost?
Are there any systems that currently use the NAND flash memory?

[timmillwood]

I dont mind waiting a bit longer for my MBP if it has this in..

but will it only make booting quicker?

becuase i bet i will leave the computer on all the time, just letting it sleep.

[storage]

so why are they being considered now? what has changed?
They will probably use a "flash filesystem" (http://en.wikipedia.org/wiki/Flash_memory#Flash_file_systems) on the flash memory, which minimizes the amount of erase/write cycles.

[PlaceofDis]

I dont mind waiting a bit longer for my MBP if it has this in..

but will it only make booting quicker?

becuase i bet i will leave the computer on all the time, just letting it sleep.

no it should help in other things that need to be quicly and frequently accessed by the OS. although i'm sure that it will have to be implemented all on the software side too, so i don't know if anyone would see any benefit from the start until its made to work well with the OS.

should also help the amount of data that gets stored during 'sleep' and waking up of your laptop.

[brianus]

I keep seeing articles like this. Don't really understand how it would work at a filesystem level. What would this do the the notion of "startup disks"? Would MacBooks ship with a special version of OS X where the OS was on flash but user and app directories were on the hard drive? Would you see multiple volumes? I'm surprised never to see these issues brought up when there's a discussion of using NAND in laptops.

[prady16]

Very interesting.. but unless we're getting 100+GB flash drives... I'll still want an hdd ;)

The NAND flash is not for HDD. It is just to augment the existing RAM.

[MoparShaha]

I certainly hope Apple is working on an "ultra-portable". None of the current laptops are small enough to replace my 12" PB.

[iBookG4user]

Very interesting.. but unless we're getting 100+GB flash drives... I'll still want an hdd ;)

though.. it'd be cool to have some non-volitile flash memory to store the OS and other critical components on.
64GB Flash memory drives are avaliable now albeit at a high price.

[CalfCanuck]

I'm sure that now that Apple is now such a big buyer of Flash RAM (i.e. nanos) that they can get pretty good pricing.

It's great to see Flash continue to spread into the portable market - I've been arguing for years here that Flash will take over the smaller storage iPods (no moving parts = $$$ saved on repair costs).

While this talks about integrating Flash into a regular computer, it would be cool when we finally see a 32 GB Flash based computer with NO MOVING PARTS! Using a combinatiuon of wireless I/O and weather roof sealing, it would be water and dust resistant and extremely robust able to be dropped.

(Anyone remeber that video about trying to destroy the nano? They even drove over it with a car and it still worked - I can't remember what it finally took, but I think they had to throw it about 40 feet into the air to fall onto concrete to kill it!)

[jhande]

Hmmm.... a 12/13" Flash based notebook, with 10+ hrs battery life? Where's my credit card :D

Seriously, I've been waiting for this for years. 30-50GB storage would do me just fine.

With flash/battery/screen tech being where it is, I'd also be interested in a sub-notebook...

Must. Not. Say........ Newton..

[p0intblank]

I can't wait until these notebooks with NAND memory hit the market. The new Intel Macs boot faster than ever before, so these upcoming models will be insane. :D

[Lynxpro]

What about placing a sizable chunk of the OS into Flash Memory? And thus, we'd return somewhat back to the days when a computer OS resided on ROM chip independent of the system's main memory.

[bloodycape]

Sony is already using 16gig flash in their UX but the down side is it is pricey, and you have to order it from japan? Maybe apple can get a good deal on 32gig flash Samsung announced a while ago and use two of them?

[CaptainScarlet]

All I know is that I ordered a MacBook for my wife on the 8-24 and the damm book STILL hasn't shipped yet!! ack!!

Next time I'll order the ram later....

[steve_hill4]

interesting implementation, but this is just rumor and the title of this thread treats it as a bit more than that.....
I agree, without wanting to sound too argumentative, shouldn't this really be a page 2?

[buffalo]

Another vote for the smaller notebook. I would love something nice and small that's does the basic things: internet, Word, iTunes, iPhoto. I wouldn't mind a Macbook, and am thinking about getting one next year but would love to have something in the 11-12" range possibly under 4 pounds.

How much would something like this likely cost? Even if it's not flash.

[drlunanerd]

If this is anything like ReadyBoost in Vista, then all it does is augment your main RAM. If you're lacking in that department it can help performance, but if you've already got plenty then it doesn't make much difference.

As the Intel Macs already boot super-quick, and the Mac's wake from sleep has always been far faster and more reliable than Windows's, I'm not that bothered about this.

[danielwsmithee]

I keep seeing articles like this. Don't really understand how it would work at a filesystem level. What would this do the the notion of "startup disks"? Would MacBooks ship with a special version of OS X where the OS was on flash but user and app directories were on the hard drive? Would you see multiple volumes? I'm surprised never to see these issues brought up when there's a discussion of using NAND in laptops.The hardware could be designed to shield any knowledge of this from the software/OS. It works in conjunction with the hard-drive much like your 8MB / 16MB ram cache on your Hard-drive works now. The advantage is that for the most commonly read items (256 MB) the HD seek time would be completely eliminated. Data throughput of Flash is not much better than a HD, but it is instantly addressable. The HD firmware will likely take care of all the details associated with this. The CPU/OS will simply ask for the data the same way it does now it will just get it sooner.

[danielwsmithee]

If this is anything like ReadyBoost in Vista, then all it does is augment your main RAM. If you're lacking in that department it can help performance, but if you've already got plenty then it doesn't make much difference.

As the Intel Macs already boot super-quick, and the Mac's wake from sleep has always been far faster and more reliable than Windows's, I'm not that bothered about this.It will also allow for much better battery usage as the HD will have to spin up much less often. This will give a decent performance improvement for all tasks because it will eliminate the HD seek time on many files.

[enda1]

^
|
What he said. ;)

Edit: Damn it!! The post above that one, #28. I should just delete this shouldn't I....

[k8to]

good news. i had wondered for a while why they don't start using flash memory. with the sizes they have now it should be doable, at least in parallel to regular hard drives, which can act as a internal back up/storage system.

Because they can only be used for X erase/write cycles.

With modern flash devices which implement on-device wear levelling, and the usage patterns employed by operating systems, your hard drive will most likely fail long before the number of write cycles will exceed the longevity of your flash device.

Swapping to flash without wear levelling would probably manage to break flash on a very active machine, but no one is going to deploy that.

[danielwsmithee]

64GB Flash memory drives are avaliable now albeit at a high price.I've seen a 3TB flash drive at work. Of course it was being made for a satellite and cost many millions of dollars.

[storage]

With modern flash devices which implement on-device wear levelling, and the usage patterns employed by operating systems, your hard drive will most likely fail long before the number of write cycles will exceed the longevity of your flash device.

Swapping to flash without wear levelling would probably manage to break flash on a very active machine, but no one is going to deploy that.
Thanks for clearing that up (y).

[k8to]

One achievable advantage of adding solid state storage is the dramatic improvement in performance of 'journalled' systems.

In journalled/transactional systems, such as databases, journalled filesystems, there are choke points in the performance where you must be assured that certain flags hit the disks before and in between other data chunks. This can involve I/O-dampening seeks and cache flushes for hardware that doesn't support I/O barriers (typical desktop level disks). With the addition of solid-state storage, you can write the transactional flags to the solid state device instantly without the concern over write-caches which will lose data on power-off.

Thus HFS+ with journalling could perform significantly better by taking advantage of a small amount of the flash space. Databases could also improve, although this is less typically a desktop type activity.

One thing I don't really understand is the proposal to spin up the hard drive less often. Typical machines these days have around a gigabyte of RAM, which can be used to buffer both reads and writes. How would adding 256 megs of flash help greatly?

One problem I see on Linux for example is that the journalled filesystem implementations write to the disk periodically, regardless of whether any I/O activity is occurring. Perhaps this could help with such an area.

-------

To those discussing executing out of flash, it's too slow. The read speeds from flash are so much slower than RAM, that no one is going to want to do this for any sort of significant amount of executable code. Additionally, since you cannot put varible segments of programs (heap, data, bss segments) in flash, there is no real prospect for "instant on" by adding significant flash to the system. However, as demonstrated by the article linked, the lack of seek-delay in solid state storage can accelerate seek-bounded I/O tasks, like booting.

[danielwsmithee]

One thing I don't really understand is the proposal to spin up the hard drive less often. Typical machines these days have around a gigabyte of RAM, which can be used to buffer both reads and writes. How would adding 256 megs of flash help greatly?

Ram does buffer your hard-drive access. Often however applications regularly flush their buffers so that the state of whatever you are working on is saved to some form of non-volatile memory HD. In case the system goes down or the application crashes. It could be possible to locate these items in flash and prevent the necessity of using the HD. A good example of this used in almost every application is error logs. They are written to quite often and are by definition never buffered. A lot depends on the size of flash used, and whether you would prefer to use your flash memory to improve boot time or improve battery life. There will be trade offs.

[k8to]

Grah, remember to check for success on error before hitting post again.

[babyj]

My understanding of the nand memory was that it would in effect by another level of cache, between the processor and the hard drive. I was also under the impression it would be Gb's rather than Mb's - Sandisk stated they had already started production of 8Gb nand memory for use in PC systems.

One of the hard drive manufacturers (Samsung I think) has announced plans to do produce hybrid drives with nand cache within the actual hard drive unit.

Nand isn't as fast as main ram but it is a lot faster than hard drives whilst using a lot less power. It isn't just for laptops either, it'll be fitted to desktops as well.

Nand is a lot cheaper than main ram so it could be a good way to almost increase main ram at a far lower price. It would work even better if you could easily access and replace the nand, upgrading it as prices continue to fall.

I'd be very surprised if Apple don't fit it as standard as 1Gb isn't going to add much to the costs. I'd of thought they'll do it asap as well, once Santa Rosa is ready - with OS support in Leopard.

[k8to]

Ram does buffer your hard-drive access. Often however applications regularly flush their buffers so that the state of whatever you are working on is saved to some form of non-volatile memory HD. In case the system goes down or the application crashes. It could be possible to locate these items in flash and prevent the necessity of using the HD. A good example of this used in almost every application is error logs. They are written to quite often and are by definition never buffered. A lot depends on the size of flash used, and whether you would prefer to use your flash memory to improve boot time or improve battery life. There will be trade offs.

How does an application flushing its buffers matter? The semantics of fflush and so on are simply "this data had better be operating-system visible when this call completes". Whether the data goes instantly to the disk or not is completely under operating system control at least for normal C / POSIX / etc semantics.

The operating system is free to buffer the data in memory as long as it feels like, balancing issues like performance vs battery life vs robustness. On a laptop, using a very large amount of ram to buffer the data for a long time is a good idea, because the system cannot lose power unexpectedly in most circumstances.

------

Edit: I should add that operating systems do provide calls (cf. fsync) for explicitly requesting that the data written to a file be committed to disk, because applications like mailservers and databases require this sort of thing.

However, normal applications do not and should not use this type of functionality.

[bigandy]

they may go into an "ultra-portable" laptop by Macworld San Francisco in January, 2007.

oh, cheers, make my MBP purchase in the next few weeks look like an out of date lettuce.

[Cinch]

My understanding of the nand memory was that it would in effect by another level of cache, between the processor and the hard drive. I was also under the impression it would be Gb's rather than Mb's - Sandisk stated they had already started production of 8Gb nand memory for use in PC systems.



I think one of the disadvantage with flash NAND storage is its ability to write (~100,000 times max). You may wonder how many time do we need to save a word file, but storage space management are done all the time with OSX with or without our knowledge. Similar to what you said, a good 8GB of NAND in a Macbook is good (4GB for OSX and the rest for other applications).

I think MRAM is on the horizon and it promises to be better than RAM, hard disk and flash combine.

Cinch

[QuarterSwede]

I think one of the disadvantage with flash NAND storage is its ability to write (~100,000 times max). You may wonder how many time do we need to save a word file, but storage space management are done all the time with OSX with or without our knowledge. Similar to what you said, a good 8GB of NAND in a Macbook is good (4GB for OSX and the rest for other applications).

I think MRAM is on the horizon and it promises to be better than RAM, hard disk and flash combine.

Cinch
The problem with MRAM is that its still too slow.

[k8to]

The problem with MRAM is that its still too slow.

Is this in terms of some practical part? My understanding is that MRAM should be faster than DRAM, making the overall speed of reads and writes of solid state storage types in the order from fastest to slowest: SRAM, MRAM, DRAM, ... (long gap)..., flash.

At least that's what my memory of this stuff is and also what loser-pedia says.

Are there practical implementation issues that make this currently false, or is it false in general?

[generik]

Wow reading these drooling posts makes me want to wait till MWSF instead, if anything the free iLife suite is worth it :cool:

[villanova329]

Bring on the final piece to Apple's marketing matrix!

Mac Mini -- iMac -- Mac Pro

_______ -- Macbook -- Macbook Pro


MacBook Mini!!! (or even Nano) =)

[extraextra]

I certainly hope Apple is working on an "ultra-portable". None of the current laptops are small enough to replace my 12" PB.

I hope so too.

[conradzoo]

At work booting is or me:

light a cigaret or get a coffee or say hello o that girl from sales or just yawn, stretch my legs and arms....

I dont care about 10 secs oe whatever less. Nah.

[tjwett]

nice! just what i've been waiting for. i'm hanging on to my 12" PB until something even smaller comes along. i'd love an ultra slim portable, even without an optical drive. i've had my 12" for 6 months now and i've yet to use the optical drive. bring on the tiny laptops!

[jhande]

I couldn't care less about the boot speed, nor whether it has oodles of GB. 30+GB of user space is fine by me. What I _do_ care about is:

Battery life
Weight
Size

And did I mention battery life? :D

[k8to]

I couldn't care less about the boot speed, nor whether it has oodles of GB. 30+GB of user space is fine by me. What I _do_ care about is:

Battery life
Weight
Size

And did I mention battery life? :D

Yeah, I'm an idiot. What i didn't realize is that flash takes no power to store data, so it's more efficient than hard drives or RAM for inactive storage.

I wonder what the profiles of flash power use are on write vs HD and RAM. I'd suspect lower than HD, higher than RAM. Thus, as a 256MB data cache or whatever, it should win on a laptop in terms of power use.

[MacinDoc]

Wow reading these drooling posts makes me want to wait till MWSF instead, if anything the free iLife suite is worth it :cool:
Or you could wait for Leopard to be released and get that free, too...

Actually, I think that's what I'll do - buy a 24" iMac in Q1 2007 after Leopard comes out.

As for this flash RAM, I agree with those who say that the primary benefit may be less power use due to reduced HD access at bootup - boot time shouldn't be much of an issue if you don't have to reboot very often. Still, I don't think it will make much of a difference overall, and I would't delay buying a MacBook just to wait for this feature.

[joeshell383]

Not Apple, but the Samsung Q30SSD (only available in Asia) doesn't have a hard drive. Only 32GB of NAND flash memory.

http://www.laptoplogic.com/news/detail.php?id=921

[sjsharks27]

What exactaly is this??? and how is it better than whats out now...also how is it better if you wait for this or by a MB when they update it to C2D??

[atlendor]

Another vote for the smaller notebook. I would love something nice and small that's does the basic things: internet, Word, iTunes, iPhoto. I wouldn't mind a Macbook, and am thinking about getting one next year but would love to have something in the 11-12" range possibly under 4 pounds.

How much would something like this likely cost? Even if it's not flash.

Totally agree. I'm waiting with credit card at the ready...:cool:

[sushi]

Neat development.

I currently have a Sharp MM20. Love it. Only weighs about 2 lbs.

I know that Apple will probably never do it, but I would love to see a 12 inch with no optical, flash memory, 120GB HD, long battery life, with a weight less than 3 lbs.

[scott523]

Another vote for the smaller notebook. I would love something nice and small that's does the basic things: internet, Word, iTunes, iPhoto. I wouldn't mind a Macbook, and am thinking about getting one next year but would love to have something in the 11-12" range possibly under 4 pounds.

How much would something like this likely cost? Even if it's not flash.A price range between MB and MBP?

Rumors of Apple looking into this Flash-caching techology has previously been reported (http://www.macrumors.com/pages/2006/06/20060615153257.shtml) with claims that they may go into an "ultra-portable" laptop by Macworld San Francisco in January, 2007.Dammit this rumor (in my mind) = more waiting! :mad:

[CalfCanuck]

Not Apple, but the Samsung Q30SSD (only available in Asia) doesn't have a hard drive. Only 32GB of NAND flash memory.

http://www.laptoplogic.com/news/detail.php?id=921
Wow, that's almost what I was talking about earlier in the thread.

Now if you could weather-seal the keyboard for dust / rain, seal most I/O ports and the battery compartment, and make the screen robust oyou would have a SWEET portable for field use. Photographers, journalists, outdoors enthusists, communters who are rough on their laptops, etc.

Edit - I forgot video users, sicne the SSD has 50+ MB/sec reads/ 28 MB/sec write transfer speeds!

[Analog Kid]

I'm not really seeing the benefit in this... It reduces boot time by a factor of two-- so it's saving me like 30 seconds every month. If this was really to improve disk storage performance, they'd put it in the disk drive (a la Samsung). If they're going to open it up for run time use, it seems there's going to be a battle to gobble up a limited resource-- tragedy of the commons...

And flash is one of those components where demand keeps out stripping supply. Constant supply headaches that have just been exacerbated by the rise in digital lifestyle devices (phones, iPods, cameras). Putting these on a motherboard is just one more sourcing nightmare.

So, why is this happening? I'd have to guess that a big reason for it is that Intel has traditionally been a leading supplier of Flash memory and has seen itself eclipsed by the likes of Samsung. They've just introduced their own line of "Serial Flash" (being careful not to refer to it as "NAND Flash") and they're trying to lock in a market.

Personally, I wouldn't need Flash in anything, but I would be stoked if this led to a ultra-light portable.

[twoodcc]

i find this good news....hope Apple adopts it and we see it in the near future

[k8to]

I'm not really seeing the benefit in this... It reduces boot time by a factor of two-- so it's saving me like 30 seconds every month. If this was really to improve disk storage performance, they'd put it in the disk drive (a la Samsung). If they're going to open it up for run time use, it seems there's going to be a battle to gobble up a limited resource-- tragedy of the commons...


Sing it. We all know shared resources can't be managed by operating systems. I mean it isn't like CPU time, HD allocation, I/O, or RAM are shared resources. Right?

Anyway, seperating it from the drive shouldn't drive up part costs, and increases flexibility for other applications (cf. journalling, transactions, cacheing under OS-control rather than device control, etc.)

[ezekielrage_99]

Been looking forward to this for years. I know that boot times have come down significantly in the last few years, but instantaneous on from startup would be pretty amazing.


I've also been hearing rumors of this for years and from the looks of this we might see it in computers very shortly (hopefully).

Besides faster booting is there any other huge benefits for the flash memory in a computer, I wasn't too sure after reading the article :confused:

[babyj]

I think one of the disadvantage with flash NAND storage is its ability to write (~100,000 times max). You may wonder how many time do we need to save a word file, but storage space management are done all the time with OSX with or without our knowledge.

Apparently there are ways to extend nand life expectancy - ensuring all of the memory is used equally and error correction for example. Seagate can't see it as being a problem as their hybrid drive will come with a 5 year warranty.

It will also depend on how it is used. If everything was going through it then there would be a lot of writes but if it was more selective (eg just os and selected application files) then it won't be that bad. Besides, if it wasn't workable and with a decent life expectancy then they wouldn't be doing it.

[babyj]

I've also been hearing rumors of this for years and from the looks of this we might see it in computers very shortly (hopefully).

Besides faster booting is there any other huge benefits for the flash memory in a computer, I wasn't too sure after reading the article :confused:

Lower power usage which should result in laptops laster longer between charges.

Otherwise it depends on the data that is stored on it - frequently used applications for example, which would then load and run quicker.

[CalfCanuck]

I've also been hearing rumors of this for years and from the looks of this we might see it in computers very shortly (hopefully).

Besides faster booting is there any other huge benefits for the flash memory in a computer, I wasn't too sure after reading the article :confused:
When one replaces the HD with Flash Memory, rather than supplementing one as this rumor seemed to state, the Samsung link pointed out numerous advantages. They note that their Solid State Drive (SSD) has faster read /write, can handle double the shock of a HD, and then is easier to retrieve data from if it fails (i.e. no heads crashing onto platters to make life hellish!).

[mdntcallr]

so, sounds like a nice update next year.

that said. sometime ill need to upgrade my laptop.

im just hoping the meroms come soon, with a nice grpahics chip and a larger hard drive. im thinking 160 gb hd.

[Analog Kid]

Sing it. We all know shared resources can't be managed by operating systems. I mean it isn't like CPU time, HD allocation, I/O, or RAM are shared resources. Right?
It's interesting though how quickly we can name those limited resources-- because we've got to think about them all the time.

Do you ever run out of CPU time-- no, things just take longer. You will run out of Flash storage though. CPU Time is essentially divided evenly among running applications-- should we partition persistent storage evenly among all applications on the system?

HD allocation is not a limited resource-- HD space is essentially limitless...

Volatile RAM is essentially limitless with good virtual memory support to the limitless hard drive. In the places where this assumption breaks, it causes pretty severe hardship as the system thrashes to disk endlessly.

I/O is a limited resource, and most system design has been devoted to reducing the number of limited I/O ports. No more parallel port, no more serial ports. USB, Firewire, Ethernet-- all are essentially unlimited resources.

Anyway, separating it from the drive shouldn't drive up part costs, and increases flexibility for other applications (cf. journalling, transactions, cacheing under OS-control rather than device control, etc.)
In a laptop, the cost will be identical-- one computer, one hard drive, one flash bank. What is soldered where won't make a difference. In a desktop though, you start running into problems again-- how many hard drives can be supported by that single bank of flash? When I start removing and inserting firewire drives-- how does the Flash know if it will ever see a given drive again?

Caching through flash is useless-- it's slow for one thing, and since a cache is transient by definition there's no reason to use Flash rather than DRAM.

[k8to]

It's interesting though how quickly we can name those limited resources-- because we've got to think about them all the time.

Do you ever run out of CPU time-- no, things just take longer. You will run out of Flash storage though. CPU Time is essentially divided evenly among running applications-- should we partition persistent storage evenly among all applications on the system?

CPU time is absolutely exhaustable. Sometimes things taking longer is not acceptable, because it impacts usability, or because applications have deadlines. If your music player cannot get sufficient cpu time to decode then the music will break up, which is generally considered undesirable. In other arenas missed deadlines can result in data loss or malfunction. An assembly line robot that misses its deadline is not acceptable. A medicine pump program that misses the shutoff deadline can kill people.

Granted there are some applications in which CPU time exhaustion is not a problem, but it still occurs, and the operating system must contend with the problem and continue to allocate CPU time to necessary system functions to keep the system working correctly in the face of the exhaustion.

Depending upon what facilities the flash storage is provided for, some form of allocation will be possible that will work for most use cases. As a fancy os-controlled cache, exhaustion won't be catastrophic. As a fixed allocation structure, a failure to acquire the desired allocation may be handled by the program, or may not resulting in failure. These problems _already_ apply to memory and disk allocation. No big new problem here.

Your claims that ram and disk are limitless are factually untrue. I certainly have dealt with real production machines which have exhausted either or both. It has been interesting noting which applications fail and which continue to work correctly in the face of exhaustion.

Caching through flash is useless-- it's slow for one thing, and since a cache is transient by definition there's no reason to use Flash rather than DRAM.

Flash transfer rates for read can easily outpace fixed disks. For write I don't know what the numbers are, but as I pointed out in another post, flash has no seeks, which can matter a lot for some loads and not much for others. Microsoft is seeing wins by prefetching data to flash devices _over USB_, so surely it must be possible to achieve wins on flash devices with more robust access paths.

For cache purposes, the reason to use Flash over DRAM is that per-megabyte the cost of Flash is lower, and Flash takes no power to leave programmed. This may not be sufficient to make it worth it to add per dollar, but those are the advantages.

[scott523]

What are the advantages of NAND Flash other than booting faster? Is it anywhere near regular RAM in terms of speed?

Is double booting speed worth the price?The reason why Intel wants to put these NAND flash chips is because not only it can boost start up speed and such, this can reduce power consumption since any data not stored on memory requires more power to fetch the data from the spinning hard drive. With this and other features included in the Santa Rosa package, it may increase battery life (I think the new 802.11n card will erase the surplus minutes).

A boring but interesting keynote (http://www.intel.com/idf/us/fall2006/webcast.htm) presented by David Perlmutter explains the overall Santa Rosa chipset.

[floatingspirit]

I'd go for a Nanobook! Or a Macnano...:rolleyes:

Bring on the final piece to Apple's marketing matrix!

Mac Mini -- iMac -- Mac Pro

_______ -- Macbook -- Macbook Pro


MacBook Mini!!! (or even Nano) =)

[Eidorian]

I've seen eDRAM (http://en.wikipedia.org/wiki/EDRAM) being mentioned for onboard hard drive caching. You still have the old 8/16 MB buffer. You tack on another 256 MB of eDRAM internally to the drive.

The thing is that hard drive manufacturers and motherboard manufacturers are both pushing for adding more drive cache.

Hard drive makers can make it seamless and OS-independent.

Motherboard manufacturers can put cache onto a motherboard and it'll work with any attached hard drive. You'll need Windows Vista or maybe Leopard to take advantage of it though.

They both want to make more money. :rolleyes:

[bloodycape]

I guess we will have to wait and see how the 16gig sony UX and that 32gig Samsung will fair in a few months. I am assuming the Samsung is going cost what 2400 to import to the state similar to the Sony UX prices? Or will it be cheaper since it is an actual laptop and not a umpc.

[lewion]

All I know is that I ordered a MacBook for my wife on the 8-24 and the damm book STILL hasn't shipped yet!! ack!!

Next time I'll order the ram later....
contact apple, that is not normal!

[RedTomato]

I expect this to be a minor functionality upgrade.

It won't effect many things.

Spending £200 on a add-on Flash Drive won't give you the same benefit as spending £200 on adding more main RAM.

Where it will come in useful is in storing information when the computer is in a power-down state.

E.g. faster startups as mentioned. However, that doesn't effect Apple much as they're rarely rebooted.

A very useful area would be longer-lasting Sleep mode. My laptops often run out of power while in Sleep. Flash drives could really help with longer life while in Sleep or more battery charge remaining when waking from Sleep.

IBM laptops have had 'Hibernate' for a while - where the RAM memory is saved to HD and read back on waking. It was nice but buggy, as often it didn't play nice with Windows, which often needed rebooting anyway.

Don't expect it to give longer battery life while in use - adding £200 of RAM would have the same effect of extending battery life anyway.

As I said, a nice incremential improvement but nothing earthshaking.

[Analog Kid]

Flash transfer rates for read can easily outpace fixed disks. For write I don't know what the numbers are, but as I pointed out in another post, flash has no seeks, which can matter a lot for some loads and not much for others. Microsoft is seeing wins by prefetching data to flash devices _over USB_, so surely it must be possible to achieve wins on flash devices with more robust access paths.
NAND flash seeks. NOR flash does not. The flash they're looking at here is NAND which has a serial access strategy. The seek time may be faster than disk, but it is paged and sequential access (25ns) is much faster than random access (25µs). Write time is 220µs. Erase is 1.5ms. All faster than disk but much, much slower than DDR DRAM.

This is great if you're using Flash instead of disk, but that's an expensive option and not what is being discussed here. For caching, it seems pointless.

For cache purposes, the reason to use Flash over DRAM is that per-megabyte the cost of Flash is lower, and Flash takes no power to leave programmed. This may not be sufficient to make it worth it to add per dollar, but those are the advantages.
Where do you see Flash being cheaper than DRAM? I know that's not true for NOR and find it hard to imagine that it's true for NAND. Disks also require no power to leave programmed. The only advantage of Flash over DRAM is that it's non-volatile its only advantage over disk it that it's faster.

The only advantage I can see is faster load times for pieces of the OS stored in Flash. It just doesn't seem worth the cost and hassle of adding that kind of complexity unless it's used for non-standard operations like playing media without needing to boot.

[tarjan]

I think that part of the idea is less of a cache as you are thinking in the traditional terms, and more of a place to hold information about your system. This way you can have critical peices of information at hand and available at any time. Like when you put your computer to sleep,not just on power up. The traditional method keeps everything in memory, which requires full power to the memory chips. Go to a flash based system and you can store a bunch of information without having to keep power active. Basically making the system somewhere in-between standby and hibernate for power savings, with no drawbacks.

You could, in theory, put that same information on a hard drive, but there is no guarantee it will not be fragmented to hell and back, slowing down transition times. If you don't use a traditional file system on the flash, you are all set. Just use something completely custom for cache only purposes with no drawbacks of requiring a traditional allocation table.

[Maccus Aurelius]

I certainly hope Apple is working on an "ultra-portable". None of the current laptops are small enough to replace my 12" PB.

A friend of mine has a 12" powerbook, it's plenty small, but it's much bulkier than my macbook, it's only wider because of the widescreen.

An ultraportable notebook would be so awesome, it's too bad that i'll have to wait while the price drops just a bit and all possible bugs get ironed out. One thing my experience with my macbook has taught me: never feel like a beta tester again. These new macs boot pretty fast, a flash driven MB would be damn near telepathic, at least ideally : )

[gnasher729]

One thing I don't really understand is the proposal to spin up the hard drive less often. Typical machines these days have around a gigabyte of RAM, which can be used to buffer both reads and writes. How would adding 256 megs of flash help greatly?

Two things: First, if anything is kept in RAM that needs to be written, you would have to be able to guarantee that everything can be written to harddisk in the worst case scenario (computer unplugged, battery doesn't work properly, computer crashes). That is difficult. With Flash RAM, everything is safe even if you lose power completely.

Second, someone published estimates about the bill of materials for iPod Nano. Apparently, Apple pays about 10 dollars per GB, so I would expect 1GB on a MacBook, 2GB on a MacBook Pro.

[Synchro]

Nobody seems to have noticed that Seagate has announced hybrid drives too. Check out the Momentus PSD (http://www.seagate.com/products/notebook/momentus.html). I've seen them in some online stores too (scan.co.uk).

They come with 128Mb or 256Mb of Flash, as well as having SATA II, 8Mb cache, 5400rpm, perpendicular recording, and up to 160Gb capacity. Sounds like a notebook user's wish-list come true to me.

[Maccus Aurelius]

Nobody seems to have noticed that Seagate has announced hybrid drives too. Check out the Momentus PSD (http://www.seagate.com/products/notebook/momentus.html). I've seen them in some online stores too (scan.co.uk).

They come with 128Mb or 256Mb of Flash, as well as having SATA II, 8Mb cache, 5400rpm, perpendicular recording, and up to 160Gb capacity. Sounds like a notebook user's wish-list come true to me.


Nice. If it runs ok in a macbook, I'm getting one.