WM5 - Persistent Storage question [Archive]

Darius Wey

08-13-2005, 04:18 AM

No, they won't.

All data and system files will be stored on ROM (as opposed to the current architecture which involves storing it on RAM), and your RAM will be used solely for program execution.

At the end of the day, this equates to a longer battery life (since you won't need to worry about powering the RAM in standby mode), zero purging of the device's contents if the battery were to run dry (since the ROM is non-volatile), and more memory for program execution.

Sven Johannsen

08-13-2005, 05:03 AM

The effect will be that ROM will hold what it does now, plus what is held in the Storage side of RAM. That's why the total ROM for a WM5 device needs to be significantly bigger, and some of the current devices are already that way in anticipation. All of the RAM you have, which is currently divided into Storage and Program pieces, will be allocated to Program.

PetiteFlower

08-13-2005, 06:10 AM

So you won't be ABLE to store anything in RAM if you have WM 5? That's kinda sucky.

Darius Wey

08-13-2005, 06:29 AM

So you won't be ABLE to store anything in RAM if you have WM 5? That's kinda sucky.

It's not sucky if you compare it to the current model. You'll have more memory dedicated to program execution, and you won't lose your data if the battery runs out. Trust me - it's a better system, and one that should have been implemented a long time ago.

The PocketTV Team

08-13-2005, 06:34 AM

If you want, you can still store your non-critical data files (e.g. your music etc) in RAM. But they will be lost is you really power-off the device (power off is different from power suspend, which is whar Pocket PC do when you hit the power button).

There are two file systems, just like in the current Smartphones. One is in Internal Flash (what you incorrectly call ROM), and the other is in RAM.

There is also a ROM, different from the Internal Flash, which is used to re-initialize everything when you do a hard-reset.

In the new WM5 Pocket PC's, i don't know if the power button will suspend (i.e. keep RAM powered), or if it will really power off the device.

Darius Wey

08-13-2005, 06:36 AM

If you want, you can still store your non-critical data files (e.g. your music etc) in RAM.

How so? Windows Mobile 5.0's memory architecture uses the RAM solely for program execution. As far as I'm aware, it'll be non-accessible.

In the new WM5 Pocket PC's, i don't know if the power button will suspend (i.e. keep RAM powered), or if it will really power off the device.

Windows Mobile 5.0 Pocket PCs will not yet support complete power on/off modes (like the Smartphone). Suspend will still be used.

The PocketTV Team

08-13-2005, 06:39 AM

If you want, you can still store your non-critical data files (e.g. your music etc) in RAM.

How so? Windows Mobile 5.0's memory architecture uses the RAM solely for program execution. As far as I'm aware, it'll be non-accessible.

I thought they were planning to use an architecture similar to the one currently used by Smartphone.

Maybe I'm wrong, though.

If WM5 Pocket PC can suspend, then I would be very surprized if they don't have a RAM file system. People will want to use the RAM on devices that have a lot of it, and in general program execution only uses a fraction of the RAM on devices with 128 MB RAM.

I'm sure that if there is no RAM-based file system in WM5 Pocket PC's, someone will create a driver to have one.

Darius Wey

08-13-2005, 06:47 AM

I thought they were planning to use an architecture similar to the one currently used by Smartphone.

Maybe I'm wrong, though.

They are. But the principle behind persistent storage is the lack of need to keep the RAM powered in the suspended state (which is why a lot of 128MB RAM Pocket PCs have below-average battery lives). Thus, all storage will be moved to the Flash ROM, while the RAM will be used for program execution. When future versions of Windows Mobile move the Pocket PC to the complete power on/off mode, the only thing differentiating the Pocket PC and the Smartphone will be the presence of a touch screen.

If WM5 Pocket PC can suspend, then I would be very surprized if they don't have a RAM file system. People will want to use the RAM on devices that have a lot of it, and in general program execution only uses a fraction of the RAM on devices with 128 MB RAM.

Now that Windows Mobile 5.0 has been introduced, the need for 128MB devices is nullified. A year or two ago, people would purchase a 128MB device because they could store more information on it. But with everything being moved to Flash ROM, there's no need for that anymore. 64MB RAM is suffice. Of course, the more, the merrier, but again, the need isn't there. Instead, now you will see the increasing trend towards 96MB ROM, 128MB ROM, and so on.

Cybrid

08-13-2005, 07:04 AM

Now that Windows Mobile 5.0 has been introduced, the need for 128MB devices is nullified. A year or two ago, people would purchase a 128MB device because they could store more information on it. But with everything being moved to Flash ROM, there's no need for that anymore. 64MB RAM is suffice. Of course, the more, the merrier, but again, the need isn't there. Instead, now you will see the increasing trend towards 96MB ROM, 128MB ROM, and so on.
Au contraire, mes ami. I'd expect that the premium devices will get even bigger in RAM, in order for power hungry users to run multiple apps all at once. I'm sure some of us forsee a need to have PIE, Textmaker, GPS and media player running all at once or some such.... :D

PetiteFlower

08-13-2005, 07:15 AM

I think it will be good to have some programs installed in ROM and have them not get wiped in case of power outage. But having it so you can ONLY install/store in ROM is going to decrease total storage space by a lot. If your device as 128 megs of ROM, then it's probably no big deal, but the one I'm looking at getting now has 64 megs in each ROM/RAM. A lot of the ROM is going to be taken up by the OS. If I can't store anything at all in RAM, I'm only going to have what, like 40 megs to store stuff? That's the sucky part. Makes me wonder if I will want to take advantage of the free upgrade I'll get from Dell this fall.

Course right now I have a 2 1/2 year old X5 that has 32/32 and a 300mh processor, so I'll still be better off, but that's not the point!

Other question - is there still going to be a way to hard reset devices purposely? Right now when you hard reset, what's in ROM stays. If EVERYTHING is going to be in ROM, then what if you want to reset to factory clean state?

jlp

08-13-2005, 08:00 AM

I thought they were planning to use an architecture similar to the one currently used by Smartphone.

Maybe I'm wrong, though.

They are. But the principle behind persistent storage is the lack of need to keep the RAM powered in the suspended state (which is why a lot of 128MB RAM Pocket PCs have below-average battery lives). Thus, all storage will be moved to the Flash ROM, while the RAM will be used for program execution. When future versions of Windows Mobile move the Pocket PC to the complete power on/off mode, the only thing differentiating the Pocket PC and the Smartphone will be the presence of a touch screen.

...

I'm highly surprised that no one have seen the gross conceptual error in that concept :evil:.

WM5 devices will STILL NEED TO POWER THE RAM!!

Indeed, if they don't power the RAM, then whenever you switch your device on again all the running programs with any unsaved data will have been wiped out!! 8O

NO ONE wants to have to remember to save their data before turning their machine off (read suspended), AND re-run all their program and access all their file whenever they turn their device on again.

So this thinking that WM5 is better in power consumption is plainly foolish!!

As is pretending WM5 devices will not have to power the RAM!!

Devices with WM5 WILL STILL NEED TO POWER RAM TO KEEP RUNNING PROGRAMS AND LOADED DATA ALIVE!!!

Darius Wey

08-13-2005, 08:04 AM

Darius Wey

08-13-2005, 08:19 AM

I think it will be good to have some programs installed in ROM and have them not get wiped in case of power outage. But having it so you can ONLY install/store in ROM is going to decrease total storage space by a lot. If your device as 128 megs of ROM, then it's probably no big deal, but the one I'm looking at getting now has 64 megs in each ROM/RAM. A lot of the ROM is going to be taken up by the OS. If I can't store anything at all in RAM, I'm only going to have what, like 40 megs to store stuff? That's the sucky part. Makes me wonder if I will want to take advantage of the free upgrade I'll get from Dell this fall.

Don't forget you'll still have the storage card to install your programs.

Other question - is there still going to be a way to hard reset devices purposely? Right now when you hard reset, what's in ROM stays. If EVERYTHING is going to be in ROM, then what if you want to reset to factory clean state?

Yes, there will still be a way.

samsonh

08-13-2005, 08:22 AM

If you can set a setting to store all data on an expansion card.... that would be sweet, 128 ram + 1 gigabite sd card storage.... wonderful..

but in its current state, I presume there is going to be a split of half and half, meaning 128mb memory = 64ram and 64application data

I wouldnt imagine windows mobile 5.0 being that much bigger than 2003se, maybe an increase in a couple of megabites, nothing too major. This will definately be very intresting! the upgrade on my hx2410 device will be very good.... Finally windows mobile can compete with palms, where even 32 megs of memory was more than enough for a power user!

Darius Wey

08-13-2005, 08:29 AM

I'm highly surprised that no one have seen the gross conceptual error in that concept :evil:.

WM5 devices will STILL NEED TO POWER THE RAM!!

Indeed, if they don't power the RAM, then whenever you switch your device on again all the running programs with any unsaved data will have been wiped out!! 8O

NO ONE wants to have to remember to save their data before turning their machine off (read suspended), AND re-run all their program and access all their file whenever they turn their device on again.

So this thinking that WM5 is better in power consumption is plainly foolish!!

As is pretending WM5 devices will not have to power the RAM!!

Devices with WM5 WILL STILL NEED TO POWER RAM TO KEEP RUNNING PROGRAMS AND LOADED DATA ALIVE!!!

No, as far as I'm aware, things will have been flushed to flash whenever the device is put into standby mode or undergoes a soft reset. To top it off, this process is done periodically and relatively quickly. So what does that mean? Once flushed, the RAM will not have to be kept powered by the battery.

Darius Wey

08-13-2005, 08:41 AM

If you can set a setting to store all data on an expansion card.... that would be sweet, 128 ram + 1 gigabite sd card storage.... wonderful..

If it's documents, you can manually save these to the storage card. If these are programs you're talking about, you can easily use ActiveSync to specify the path of installation - so if you want it to go on the storage card, you will be able to do it. But that's not a feature new to Windows Mobile 5.0.

but in its current state, I presume there is going to be a split of half and half, meaning 128mb memory = 64ram and 64application data

Correct. That's the way current Windows Mobile devices work.

I wouldnt imagine windows mobile 5.0 being that much bigger than 2003se, maybe an increase in a couple of megabites, nothing too major.

Right again. If I recall correctly, the base Windows Mobile 5.0 image is under 20MB. Once OEMs perform their self-modifications to it, you can expect to add a couple more megabytes, but whatever the case, it won't blow out to be a supersized version of Windows Mobile 2003/2003 Second Edition.

gwinter

08-13-2005, 01:18 PM

No, as far as I'm aware, things will have been flushed to flash whenever the device is put into standby mode or undergoes a soft reset.

No, jlp is right. During standby, power is still applied to the RAM, which means if power is removed, unsaved data will be lost. But the advantage compared to the old model is:

- Only unsaved data is lost. Other things like registry, installed programs are in ROM and thus will survive total power lost.
- Because of the point above, tolerance to low battery situation is relaxed. Currently, the device will reserve quite a lot of charge so that the RAM will survive for approximately another 72 hours. During this time, you won't be able to power-up the device. In WM5, no reserve is needed. So you can run the battery flat. This translates into longer runtime.

What happens when you power-up after going into a flat battery situation? My guess is, it will be like a soft-reset in the current model.

So you won't be ABLE to store anything in RAM if you have WM 5? That's kinda sucky.

That's right. No storage in RAM, by default. Which is something that Mike on the Windows Mobile team talked about in the team's blog. The point then was, for a power user who does a lot of browsing on Pocket Internet Explorer, how to relocate the cache so that you don't wear down the ROM prematurely. Relocating to external storage card is possible, but there is a slight performance penalty compared to RAM. Thus, the solution would be a RAMdisk driver, so that you can store stuff in RAM again. There is currently no driver for WM5 yet. But considering that, a RAMdisk driver does exist in Platform Builder, it will be only be a matter of time until someone, or a software vendor comes up with one.

Darius Wey

08-13-2005, 01:32 PM

No, jlp is right. During standby, power is still applied to the RAM, which means if power is removed, unsaved data will be lost.

I stand corrected. I re-read the information on the 72 hour rule and I seem to have misinterpreted it the last time round. It's a case of extending battery life due to the removal of the artificial battery restriction, not a physical one. Sigh, I need to learn to stop reading these things at odd hours of the morning. :roll:

Anyway, thanks for the heads-up. ;)

gwinter

08-13-2005, 02:19 PM

As an aside, ROM stands for Read-only Memory, which indicates that they cannot be written to. Which is correct, back when the term was coined. The circuitry, and hence the information inside the chip is fixed and cannot be changed.

Since then technological advancement has given us other variants of ROM, for example PROM, EPROM, EEPROM, and of course FlashROM. Contrary to the "ROM" in the name, EPROM, EEPROM and FlashROM can be re-written to. The name ROM stucked, because they are supposed to function just like the hard-wired ROM. But the new re-write ability gives rise to new possibility not available before. For example, let's compare the way to update products that use EPROM, EEPROM and FlashROM respectively.

EPROM - extract the chip, expose the chip to UV light source to erase, then plug it into a programmer device to re-program the chip.
EEPROM - extract the chip, plug it into a programmer device to erase and re-program the chip.
FlashROM - re-program is done in-device, i.e. the chip stays in the circuit all the time.

As we progress, we can see it is getting easier and faster to re-program the chip, culminating in the final result that we have today. Memory card that can be re-written often and quickly. In other words, it doesn't really look like ROM, does it? But, as I said, the name still stuck. Something to think about the next time you encounter the word FlashROM...

Paragon

08-13-2005, 08:13 PM

Au contraire, mes ami. I'd expect that the premium devices will get even bigger in RAM, in order for power hungry users to run multiple apps all at once. I'm sure some of us forsee a need to have PIE, Textmaker, GPS and media player running all at once or some such.... :D

Not really a contrary. ;) I did say, "the more, the merrier", purely for the reasons which you have said, but what I was stating was that it becomes more of a want than a need. 64MB-96MB can get you by purely for program execution purposes. But don't get me wrong - j'adore 128MB. :P

Darius is absolutely correct here.

If you have a WM2003 device with 64/64 ROM/RAM and you upgrade it to WM5.0, you get a 200% increase in available RAM for running programs and a loss on the storage side when you share all storage duties in the 64mb of ROM. How many times have we seen the available amount of program memory double in the life of PPCs?

If you were to double the amount of RAM on that same device you would have a 400% increase in program memory, and still very little place to store everything. This is exactly why we are seeing most WM5.0 devices announce that they will have a 64mb RAM and 128mb of ROM configuration. This configuration doubles the available program memory, and storage space holds its own or has a small increase.

And, as Darius stated...I too will take 128mb of RAM as well, but if I can only put my memory where it is needed most....on a WM5.0 device, I'll choose ROM.

Dave

samsonh

08-13-2005, 08:23 PM

but in its current state, I presume there is going to be a split of half and half, meaning 128mb memory = 64ram and 64application data

Correct. That's the way current Windows Mobile devices work.

I wouldnt imagine windows mobile 5.0 being that much bigger than 2003se, maybe an increase in a couple of megabites, nothing too major.

Right again. If I recall correctly, the base Windows Mobile 5.0 image is under 20MB. Once OEMs perform their self-modifications to it, you can expect to add a couple more megabytes, but whatever the case, it won't blow out to be a supersized version of Windows Mobile 2003/2003 Second Edition.

What 2 more questions, isnt the way most 128mb devices now work like 64mb rom containing the oem's modified os, 32mb application data and 32mb ram.

Does the 20mb+ os contain the onboard applications like windows mobile and office? If it did, whats your estimate on the total size of a base install?

The reason I think applications all on card, data on application data part of the onboard memory, and the rest ram, would be good because the windows mobile os is highly unorganized, I have about 100 folders of applications on the root directory of the sd card, I have to navigate around all that, to find my files. Currently, the size of the application data (32mb) is not quite enough to place applications in.

Also, what about this silly thing called ipaq data store? Will that just disapear?

Samson

Duplicate posts deleted - DW

Paragon

08-13-2005, 08:27 PM

Also, what about this silly thing called ipaq data store? Will that just disapear?

Samson[/quote]

Yes. Well, no. Well, sort of. ;) In effect Ipaq "File Store" becomes your total memory for onboard storage.

yankeejeep

08-13-2005, 11:12 PM

What 2 more questions, isnt the way most 128mb devices now work like 64mb rom containing the oem's modified os, 32mb application data and 32mb ram.
The way most devices now report memory is xx mb ROM (either 64 or 128, including the area holding the ROM image), with the area set aside for the OS image varying between 20 and 30 mb, depending on the maker. So you will end up with user-accessible FlashROM (in iPaq called the file store) of anywhere from a little over 30 mb to about 100 mb, depending on your device. These current devices also sport either 64 or 128 mb of RAM (main memory), which the OS likes to divide evenly between storage and program execution functions. This division is dynamic and is changed changed by the OS as your device usage consumes the RAM area.

The devices that currently offer a configuration of 64 mb RAM and 128 mb FlashROM are best equipped to take advantage of WM5's memory usage (and then there's the iPaq 2755 with 128 of each). With 64 mb available for program execution, few users are going to see 'out of memory' errors due to RAM availability and most of us can also fit what we currently carry in FlashROM and main memory storage into 100 mb of FlashROM (persistent storage) without a problem. As long as we can still access apps installed to card locations and open documents stored on cards, we will be happy campers.

Now if they could just address that pesky, predefined limit on system resources... My understanding is that it is still present in WM5, but I'm trying to convince myself that it's just a vicious rumor.

Patrick Y.

08-14-2005, 10:38 PM

Darius Wey

08-15-2005, 03:06 AM

I know that there is a lot of discussions over this already, but my biggest concern about flash storage is the speed. Even though most people said it will be almost undetectable, I did feel A LOT of differences when I install and run programs like Leo's Flight Simulator, Taiyouki, etc. Also, Internet Explorer slows down significantly while loading pages if I change the cache directory to flash ROM or SD card.

I'm generalising here, but for the most part, the speed differences will be negligible. Sure, your initial synchronisation with hundreds of e-mails, appointments, tasks, and contacts might take a little longer, but subsequent synchronisations with the typical one or two alterations will still be as zippy as ever. Huge applications may take a little longer due to the large dataset which need to be read/written constantly, but I'm sure with all your day-to-day applications, you have very few of those.

At the end of the day, things might seem a little slower at first, but it's something you'll adapt to. Nothing is going to slow down to a snail's pace. If anything, you might only notice a minute portion of a second difference in most cases, and perhaps a one or two second difference for those major processes.

PetiteFlower

08-15-2005, 03:19 AM

So what are the other advantages being talked about in the new OS?

Darius Wey

08-15-2005, 03:53 AM

So what are the other advantages being talked about in the new OS?

I'd say that the significance of each of Windows Mobile 5.0's features is in the eye of the user, but here are some of the features new to the platform:

• Persistent storage
• Updated Contacts and Messaging
• Inclusion of Pocket MSN
• Option of OEMs integrating Voice Command into the device
• Improvements in Internet Explorer Mobile, Word Mobile, Excel Mobile, as well as the inclusion of PowerPoint Mobile
• Updated Windows Media Player 10 Mobile (now features ratings support)
• Support for new wireless networks
• A new set of APIs for developers
• Direct3D Mobile
• Updated Phone application
• ActiveSync 4.0
• USB 2.0 support

There are a few other changes, but they're more under-the-hood changes.

PetiteFlower

08-15-2005, 04:38 AM

Man.....now I'm really torn for what to get, X50 or X30....no fair!

Darius Wey

08-15-2005, 09:55 AM

Man.....now I'm really torn for what to get, X50 or X30....no fair!

My two cents - if you can afford the X50v, I'd go with that. If the idea of a VGA screen, a faster CPU and the Intel 2700G isn't something you're interested in, then stick with the mid-range X50 (520MHz). In my opinion, they're both better choices over the X30, which Dell will not be supporting with the Windows Mobile 5.0 upgrade.