Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Drives built to be run 24x7 are known as "enterprise" class and they usually have SAS interfaces on them. In the past these would have been your high end SCSI or Fibre Channel devices. They feature higher performance, better error detection and recovery, and more features (physical and firmware). These drives are generally more expensive. Consumer grade drives are a bit of a different - they are a volume business so cost is everything. While the consumer grade hard drives are not built to the same standards that enterprise class hard drives are, warranty returns have a higher relative cost because the profit margins are so slim, so the manufacturers still want them to go out the door and never come back. The key to a long life for a hard drive is to minimize the vibration and the heat. Vibrations are hard on the servos. "Gentle usage" might make a small difference, but nothing in comparison to vibration and heat. The fan in your big desktop power supply might be more of a threat due to the vibration it creates than any prolonged seek activity. And don't worry about SSDs displacing "spinning rust" anytime soon ... their cost and capacity has to improve a lot. But for raw speed, they can't be beat. And for laptop use, not having to worry about heads crashing is a nice feature too. Mike -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Op 4-11-2011 2:25, Jack schreef: > Re: the rest of your comments, I agree, SSD/FLASH/"whatever" hard > disk replacements have their advantages, but at present, the cost > of REGULAR hard disks makes SSDs a "niche" market only. Perhaps > if SSD costs drop (a LOT!), and most such "reliability" issues go > away (COMPLETELY!), they may replace most traditional hard-disks. > But, Seagate "et al" keep making their drives cost less, too, and > so I expect to "live out MY life" [age 66 now] using a HARD disk! I wonder if SSDs will go reasonably mainstream now since harddisk prices have nearly doubled and OEM vendors will run out of stock in a month or so. Requires consumers to look beyond capacity only ofcourse. Most systems are still sold with harddisks as the systems need to be cheap to appeal as a low cost device to most consumers. The enthousiast public seems to use a single SSD nowadays (for operating system and other programs benefitting from very low access times) combined with 1 or multiple harddisks for the usual (media) storage needs. A niche indeed, for now (and having multiple SSDs gets bloody expensive). I'm not entirely sure about reliability. Backups of data are a necessity anyways, and if not doing so, apparently replacing one defective disk by a fresh good/new one isn't an issue either. Harddisks are more of a commodity though, and more affordable. I just hope future systems can still run DOS (despite UEFI replacing BIOS with the fear of only being able to run Windows due to Secure Boot), including booting from USB3 at its full speed so a fast USB3 flash disk can have its (4GB?) content copied to system memory in a few seconds. 4GB RAM limit in DOS or not, I wonder if the MEMDISK feature of Syslinux can load 4+ GB (harddisk) images to system memory. But that's kinda offtopic hehe. -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Eric, >> Sad how a simple "battery" is not included in such devices, so maybe >> low-power DRAM could be used for faster writes and longer lifetimes. > > Batteries are usually limited to high-end products ... Get them down into LOW-end products, and I might be more interested! > Hard disks also come in variants for 24/7 use and those for PC. Nice to know, but may not be necessary. My 2003-2006 Maxtor disk ran exactly for its 3 years. My 2006 Western Digital is now over 2 years PAST warranty and giving absolutely NO ill effects, likely due to UIDE that I did not HAVE till late 2006. Not just UIDE, but your LBAcache or ANY constantly-used disk caching program should help make "regular" PC hard disks last a LOT longer! >> But knowing how manufacturers make such disks last EXACTLY >> their "warranty period", I really doubt it! > > I also doubt that they would last that long if HEAVILY used, > maybe just okay for the manufacturers to replace those which > are used more than predicted and thus break during warranty. "We may never know", since even I did not realize how far beyond its 3-year warranty my W.D. disk drive is, till AFTER I wrote the above! "Heavily used" may no-longer exist, if UIDE or LBAcache are present! >> if you use a FLASH based device in an environment with lots of writes >> then you expect to be replacing it on an accelerated schedule. > > The "lots" should probably be "LOTS" there: As mentioned earlier > in this thread, SSD already ship with extra capacity. They keep > track how often which area is used and just use fresh areas when > they predict or sense some area to be over-used. Different from > harddisks, over-used areas are not lost for reads but for writes > so data is normally never lost, just the capacity decreases ... Hard disks almost NEVER "lose" data, as their firmware does much the same as you note above: If a sector/track/whatever seems to be getting unreliable, the disk assigns the area to an alternate and copies its date there, while it still can! Only if a hard- disk runs OUT of alternate areas does it then start posting REAL errors to us "outsiders"! > Also, the sweet spot for SSD sizes, price wise, is 60 to 500 GB > at the moment, much closer to 1 Euro per GB than to two ... Last I heard, a Euro was about $1.33, meaning that a 120-GB hard disk for only $40 (30 Euros) is far more of a bargain. Each of my "30 Euros" buys 4-GB of hard disk, not less than 1-GB of SSD! >> NOT concerned about absolute speed (not with UIDE, anyway!) > > With the sizes of UIDE that you run, you could actually boot from > DVD and then use a RAMDISK, which big UIDE caches are similar to. I could, but I prefer a hard-disk that need not be copied up to a RAMdisk each time I boot. In fact, I do NOT run any "huge" UIDE cache -- I actually run a special variant of UIDE2 using a 500-MB cache, since my system has only 1-GB memory.With V6.22 MS-DOS (19.5K of free HMA re: no FAT32, Win95/98 or long-filename Krud), most of my driver and its search table for 500-MB "fits" into the HMA, and I get a faster UIDE2-style driver for only my normal 944 bytes of upper-memory! >> nor power consumption > > SSD are similar in power consumption to 2.5 inch harddisks ... Nice to know, but does not matter for people like me, who have a "desktop" system with a virtually "unlimited" 400W power-supply! >> but I AM still "concerned" over all noted in this thread >> re: FLASH-disk "cycle limits"! > > There seem to be some notorious SSD models which just break down > completely, but as far as I could tell, none of those was due to > exhausted flash write cycles. It rather seems to be weak firmware > (we both know that firmware is no quality market today) ... "Sucks!" is the "operative" word, there! Re: the rest of your comments, I agree, SSD/FLASH/"whatever" hard disk replacements have their advantages, but at present, the cost of REGULAR hard disks makes SSDs a "niche" market only. Perhaps if SSD costs drop (a LOT!), and most such "reliability" issues go away (COMPLETELY!), they may replace most traditional hard-disks. But, Seagate "et al" keep making their drives cost less, too, and so I expect to "live out MY life" [age 66 now] using a HARD disk! Jack R. Ellis -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Jack, > Sad how a simple "battery" is not included in such devices, so maybe > low-power DRAM could be used for faster writes and longer lifetimes. Batteries are usually limited to high-end products. Also, DRAM uses quite a bit of electricity, so the battery would be more for "swapping" the contents to flash while power is not there. > With hard disks, one just "uses them", with no need or worry Harddisks also come in variants for 24/7 use and those for PC. > But knowing how manufacturers make such disks last EXACTLY > their "warranty period", I really doubt it! I also doubt that they would last that long if HEAVILY used, maybe just okay for the manufacturers to replace those which are used more than predicted and thus break during warranty. >> if you use a FLASH based device in an environment with lots of writes >> then you expect to be replacing it on an accelerated schedule. The "lots" should probably be "LOTS" there: As mentioned earlier in this thread, SSD already ship with extra capacity. They keep track how often which area is used and just use fresh areas when they predict or sense some area to be over-used. Different from harddisks, over-used areas are not lost for reads but for writes so data is normally never lost, just the capacity decreases. As the SSD initially has much more capacity than visible for users, it can keep working perfectly from the user perspective for very long time even at relatively heavy use. We even use SSD for some database servers, which of course have backups outside SSD, but I think those SSDs will still live much longer than needed and we will replace it when we run out of space, much before it breaks. Also, the sweet spot for SSD sizes, price wise, is 60 to 500 GB at the moment, much closer to 1 Euro per GB than to two. For the more freedos4kids like sizes, you can still get 8 GB SATA SSD for 15-30, while you would only get 1 or at most 2 GB IDE DOM for the same price. There are also not that many IDE SSD, but I saw a 16 GB one for 25 Euro with 40 pin ZIF connector (for subnotebooks?). So as you can imagine, the big market for SSD today is SATA, with some extra models designed directly as PCIe cards because that is potentially faster than SATA depending on your SATA controller... You can get SSD in sizes of up to circa 1 TB, but of course at 1 Euro per GB that cannot be compared to harddisks where you will easily pay less than 1 Euro for 10 gigabytes today even for some modern small and power efficient 2.5 inch models. USB sticks are a completely different story - they are commodity stuff today, when people run out of space or a stick breaks, they just buy the next stick, so there should be lower quality, speed and wear-leveling compared to SSD, also because most users only access their USB sticks occasionally and do not use it as disk. > NOT concerned about absolute speed (not with UIDE, anyway!) With the sizes of UIDE that you run, you could actually boot from DVD and then use a RAMDISK, which big UIDE caches are similar to. > nor power consumption SSD are similar in power consumption to 2.5 inch harddisks, but as they do not spin, they can enter and leave idle mode very quickly, so they can easily be idle much more than a conventional harddisk. > but I AM still "concerned" over all noted in this thread > re: FLASH-disk "cycle limits"! There seem to be some notorious SSD models which just break down completely, but as far as I could tell, none of those was due to exhausted flash write cycles. It rather seems to be weak firmware (we both know that firmware is no quality market today) which is likely to get stuck in unrecoverable data status when you power down or crash the PC in unexpected ways too often. Such "bricked" drives apparently need at least formatting to recover, although some can be debugged/fixed with special "serial console" cables. I checked some estimates online - even when you always fill the whole SSD at max speed, not taking time to read any data, usual sizes and speeds of SSD still mean that it takes years to wear out the cells themselves thanks to over-capacity and wear-level, and typical warranty periods reflect that. Consumer SSD seem to be designed for less intense access but again, if you do not overwrite, defrag, wipe or similar your whole disk all the time, you will write to much smaller areas than you read. Apparently 2- or 3-bit, especially high-density MLC flash can handle 1k-10k write cycles, but high end SLC is more like 100k cycles but at a much higher price, often server products. The MLC based consumer SSD have 10s of percents of extra capacity internally to be able to replace worn out cells automatically. Wikipedia: floating-gate NOR flash can even achieve 1M writes SLC (single level cell) and still 100k MLC (multi level cell) but only CF used to use NOR flash, NAND flash is much smaller and USB sticks, SD cards and similar use it, as do most SSD to fit really large amounts of storage into common 2.5in housi
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Mike, > Most modern flash devices have cells that are writable at least 10 > times that - 100,000 cycles is the minimum you will find. Better > devices have even higher cycle counts. Glad to hear, but I would still prefer a hard-disk whose lifetime is measured in "years", not in "cycles". > DOM products have FLASH in them - Nobody said anything about DRAM. > If they had DRAM they would have to be continuously powered. Sad how a simple "battery" is not included in such devices, so maybe low-power DRAM could be used for faster writes and longer lifetimes. > Products like Disk on Module that are designed as hard drive > replacements usually have better wear leveling capability than > standard USB "thumb drives", as the directory meta data update issue > is well known. SSDs take this to another level by "over provisioning" > which means including more capacity than is advertised so that they > will have enough spare capacity to make it to their rated lifetime. I have never used any sort of "solid state" memory devices to replace a hard disk, so the whole thought of "wear leveling" is a bit foreign to me. With hard disks, one just "uses them", with no need or worry about such techniques, for their 3- or 5-year lifetime.Maybe hard disks could last better, using a cache or other "access minimization" schemes -- But knowing how manufacturers make such disks last EXACTLY their "warranty period", I really doubt it! > For applications where fast access is required nothing can beat a > FLASH based device. Part of the equation there involves unit life; > if you use a FLASH based device in an environment with lots of writes > then you expect to be replacing it on an accelerated schedule. The > write and read throughput is far above what a conventional spinning > disk can provide, although the capacities are far smaller. Shall stay with hard disks, then. On my home "desktop" system, I am NOT concerned about absolute speed (not with UIDE, anyway!) nor power consumption, but I AM still "concerned" over all noted in this thread re: FLASH-disk "cycle limits"! For me, and I expect a LOT of others like me, a "garden variety" $40 hard disk should do just fine WITHOUT any such "concerns"! Jack R. Ellis -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Op 3-11-2011 20:56, mbbrut...@brutman.com schreef: > For applications where fast access is required nothing can beat a > FLASH based device. Part of the equation there involves unit life; if > you use a FLASH based device in an environment with lots of writes > then you expect to be replacing it on an accelerated schedule. The > write and read throughput is far above what a conventional spinning > disk can provide, although the capacities are far smaller. Odd, this conversation isn't entering my mailbox in the correct order, maybe winter time (daylight savings time adjustment). Anyway, the only thing faster than a SATA (or SAS) SSD is a PCIe SSD, which in turn is overthrown again by DRAM-based solid state disks (though most of them have given up due to much lower capacity compared to flash). -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Jack, Most modern flash devices have cells that are writable at least 10 times that - 100,000 cycles is the minimum you will find. Better devices have even higher cycle counts. DOM products have FLASH in them - Nobody said anything about DRAM. If they had DRAM they would have to be continuously powered. Products like Disk on Module that are designed as hard drive replacements usually have better wear leveling capability than standard USB "thumb drives", as the directory meta data update issue is well known. SSDs take this to another level by "over provisioning" which means including more capacity than is advertised so that they will have enough spare capacity to make it to their rated lifetime. For applications where fast access is required nothing can beat a FLASH based device. Part of the equation there involves unit life; if you use a FLASH based device in an environment with lots of writes then you expect to be replacing it on an accelerated schedule. The write and read throughput is far above what a conventional spinning disk can provide, although the capacities are far smaller. Mike -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Op 3-11-2011 21:05, Jack schreef: > Absolutely UNBELIEVABLE to me that FLASH devices are used AT ALL in > hard-disk replacements!! Last I knew, FLASH devices are writeable > only about 10,000 times. That is a LOW number of writes for disks > if one considers DIRECTORY updates that any DOS system will do VERY > often!! Even using an old "Write Back" (delayed-write) cache like > SMARTDRV, or Norton NCACHE2, I doubt that writes could be minimized > enough to make limited-life FLASH device "disks" worth their cost!! It's individual cells that are only rewriteable a limited number of times (might be 10K indeed as you mention). A nice little technology called Wear Leveling spreads out the writes pretty well (though quite a lot of static data might mean this won't go that well). For all things besides cost and data recovery, a Solid State Disk is well worthwile (reduced access times, no noise, hardly any heat, etc). It acts same as a conventional harddisk, though the technology of NAND flash and controllers has its peculiarities. Disk-On-Module and simple USB flash drives are a whole different thing, they're quite basic (single-channel for example). The exception is some fancy expensive USB3.0 flash sticks which can do sequential reads and writes over 100MB per second. > If the DOM products have normal RAM chips (not FLASH types) and are > as "compatible" with IDE controllers as everyone seems to say, then > my next "hard disk" purchase shall be another actual HARD disk or a > DOM module if necessary, NOT any sort of FLASH type! Allows me to > stay with UIDE, which may not use delayed-writes but takes only 944 > bytes of upper/DOS memory [plus a bit of "invisible" HMA] and gives > me up to 4-GB caches! Try to get even 1-GB using any "Write Back" > cache, and I have 5 words for you: "Good LUCK -- You'll NEED IT"!! Best of both worlds would be a Seagate Momentus XT harddisk (not currently though, harddisk plants are underwater in thailand, causing huge price increases) as it's a conventional harddisk with a small amount of flash memory as buffer. SSDs are worthwile but a lot of investigation is needed so people look beyond best-case scenario's regarding sequential speed and disregard quality/reliability (hello OCZ/SandForce and ancient JMicron controllers) and features (buffers, powerloss, TRIM, SCSI unmap command, other ways of garbage collection) I tend to run DOS nowadays from either inside an emulator, or from a USB Flash drive. No access to my SSD in that last case, most drives nowadays are converted to the Windows world (100% capacity of drive as NTFS for Windows). -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
>> On the topic of wear leveling I would go with the DOM products, as >> they are designed as hard drive replacements. It's pretty easy to >> burn up FLASH so wear leveling is important. > > FWIW, they claim that FLASH has unlimited read capability, but is > limited in the number of writes. So, at least theoretically, > wear-leveling should only come into play when writing to disk. To > extend the life of the system, you should try to do as much as you can > in RAM (like using RAM disks for temporary files, etc.) and minimize > writes as much as possible. This is true for "regular" hard drives as > well. Absolutely UNBELIEVABLE to me that FLASH devices are used AT ALL in hard-disk replacements!! Last I knew, FLASH devices are writeable only about 10,000 times. That is a LOW number of writes for disks if one considers DIRECTORY updates that any DOS system will do VERY often!! Even using an old "Write Back" (delayed-write) cache like SMARTDRV, or Norton NCACHE2, I doubt that writes could be minimized enough to make limited-life FLASH device "disks" worth their cost!! If the DOM products have normal RAM chips (not FLASH types) and are as "compatible" with IDE controllers as everyone seems to say, then my next "hard disk" purchase shall be another actual HARD disk or a DOM module if necessary, NOT any sort of FLASH type! Allows me to stay with UIDE, which may not use delayed-writes but takes only 944 bytes of upper/DOS memory [plus a bit of "invisible" HMA] and gives me up to 4-GB caches! Try to get even 1-GB using any "Write Back" cache, and I have 5 words for you: "Good LUCK -- You'll NEED IT"!! -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
> On the topic of wear leveling I would go with the DOM products, as > they are designed as hard drive replacements. It's pretty easy to > burn up FLASH so wear leveling is important. FWIW, they claim that FLASH has unlimited read capability, but is limited in the number of writes. So, at least theoretically, wear-leveling should only come into play when writing to disk. To extend the life of the system, you should try to do as much as you can in RAM (like using RAM disks for temporary files, etc.) and minimize writes as much as possible. This is true for "regular" hard drives as well. -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Hi Eric, I don't have a lot of experience myself, but a lot of my fellow hackers who specialize in obsolete machines have reported problems with CF cards. While CF cards are supposed to emulate IDE devices, a lot of the newer ones do not support CHS addressing and do not work in older machines. The DOM style products are designed to be drop-in replacements, so there will not be an issue. Older CF cards generally work as IDE substitutes. Newer ones may not. On the topic of wear leveling I would go with the DOM products, as they are designed as hard drive replacements. It's pretty easy to burn up FLASH so wear leveling is important. Mike -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Hi again! Sorry to react in two mails, but flash disks are a nice topic :-) > Thanks Michael for the heads-up on DOM technology - it had completely > missed my radar and after a bit of research I agree with your advise > entirely to go with that rather than SDcard/CFcard+IDE adapter... In general, the performance of CF is better (fast PIO, some even UDMA) compared to SD (fast serial communication). But then, IDE is vanishing slowly while SD market is still growing, so that will change. You can use SDs card with a simple USB cardreader or full SD-IDE controllers. >> ...you should "test" UIDE on your systems using SSD disks... Yes, for example I encountered some CF which would just hang a while from time to time, really annoying when using them as disk on a PC. >> If not, only a minor loss, as SSD disks are so fast that they really >> should not need caching. You can then run UIDE with its /N1 switch >> which causes it to ignore hard-disks but continue to cache diskettes >> and CD/DVD drives. They need caching, for they are otherwise SLOW! Caching CD/DVD is a really good idea yes. However, CF and SD cannot be compared with dedicated SSD for PC: A modern SSD contains cache and a lot of clever firmware to load-balance and wear-balance to have a fast disk which lives for a long time. A low-end version of CF / SD may not have any caching / balancing at all, but your mileage may vary. In any case, flash based storage (CF, SD, USB sticks, SSD, DOM and so on) has often very fast read access time and nice BULK write speeds. Their bad side is that doing many small writes can be very slow, as each actual flash write takes quite some overhead in hardware and only caching and pooling and balancing done by the smart SSD (also, but in lower degree by the smart USB stick / other flash disk) itself hides that from you. So, just in case you happen to have a classic *write* pooling cache a la SMARTDRV or NWCACHE around, I would be happy to hear from you about performance effects of in particular lower "delayed write" settings as "at most 64 kB pending for at most 1/2 second", or "pool writes while inside one block of 16 kB (or even only 4 kB) if possible". Thanks :-) My theory is that, in particular for disks not tuned towards DOS use, pooling things a bit will make a difference. While DOS may update the FAT word by word, other filesystems and operating systems may pool all writes in units of 4 kB or much larger. Modern SSD and even harddisks may even be tuned towards having all I/O in aligned multiples of 4 kB. Of course this is also something that your software can work on a bit, without help from DOS and caches: Access data in larger chunks, try to change file properties less often in larger steps (e.g. file size) etc. Regards, Eric -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Hi Mike, Andrew, > You should look for a product called "Disk On Module". They are > composed of FLASH chips and are designed to be direct replacements for > IDE hard drives. Unlike a lot of CF cards that can be used with an CF > to IDE adapter but might not support CHS addressing, DOMs are designed > as IDE replacements so they do proper wear leveling and will fully > emulate an IDE device, including both CHS and LBA addressing. > (A lot of newer CF cards only do LBA addressing.) So far, I never had problems with CHS versus LBA and for me CF cards *would* be full replacements for IDE disks with a simple mechanical adapter... CF cards already "speak" IDE, no extra controller needed. HOWEVER, I get the impression that CF cards are optimized for use in digital SLR cameras: So they are fast when you write a few files of a few MB each while taking pictures... Yet they are not that fast if you write many small files or want to copy around ISO images etc ;-) On the other hand, running Windows 3 from USB sticks with BIOS USB 1 drivers is no fun either - slow transfer speed and low IOPS number of accesses per second. Something as old as Windows 3 of course will easily fit inside a RAMDISK today even on an old computer :-p I think DOM targets a very specific market, which you may also see in their prices. For a simple Child FreeDOS computer, any storage will be good enough, be it USB sticks (glue a micro one to the port if you worry about vandalism) or SD cards (even embedded system and server boot disks are happy enough with SD) or CF cards or DOM :-) And when you worry about speed - copy things to a RAM disk at boot. > DOMs come in both 40 and 44 pin varieties and range in size from 32MB > to 4 or 8GB. Actually you might even be able to find a bit of storage in the BIOS chip of something if you only need 32 MB of space, who knows? Hehe. > Assuming the BIOS of your machine can autodetect hard drives, using a > DOM as a replacement for a hard drive should be easy. Some early > machines restrict the choice of hard drive by hard coding the BIOS to > only accept certain models; those BIOSes need to be patched... Never happened to me, although 20 years ago, I had a BIOS which was only able to do CHS in the old "512 MB limit" style for DOS, with an extension for "more cylinder bits in the head number byte" which let you reach 8 GB in a totally incompatible way to the "up to 256 heads but only 1024 cylinders" way of modern BIOSes that DOS would expect. > But a conventional IDE BIOS should work fine with a DOM. Also worked fine with CF, just the performance even of the best CF that I have is much less exciting than that of a PC-oriented SSD ;-) Eric PS: SOME CF also have the problem to "hang" from time to time if you keep them too busy - cameras do not, but on PC it really annoyed me. -- RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Cheers Jack and Michael, Apologies, Jack, for my typo - yes I meant UIDE instead. Thank you for your clarification on its caching operation, and I look forward to testing it on a pet project “when my boat comes in”. (Actually, maybe FreeDOS users could justifiably consider themselves as “Frugal Kings” rather than “Charlie Poor-Boys”??) Fingers crossed that I won’t need a BIOS patching for the Toshiba Satellite Pro 430CDS’s - I’ve not yet spotted a motherboard I recognise on the FreeBIOS lists (or whatever they are called now) and patching sounds a bit drastic for my expertise level. Thanks Michael for the heads-up on DOM technology - it had completely missed my radar and after a bit of research I agree with your advise entirely to go with that rather than SDcard/CFcard+IDE adapter, and probably better value over the life of the unit. Looking at various product specs a DOM would probably outlive the laptops I have in mind for them - but any surviving components will just be added to the next candidate to rescue from landfill, Many Thanks Andrew Robins On Tuesday, November 01, 2011 6:39 PM, "Jack" wrote: > > Andrew, > > > I anticipate replacing the dying and clunky old hard-drives for SD > > cards on a 44-pin IDE adapter for better performance and improved > > efficiency. I imagine that the recent improvements with FreeDOS' > > EIDE would facilitate a hardware upgrade like that - am I > > understanding that correctly, please? > > I am the author of the UIDE disk/CD/DVD caching driver, and I assume > your reference to "EIDE" is in fact addressing the UIDE driver. > > I have not tested UIDE with "SSD" disks, nor has anyone commented on > such testing. FreeDOS users are often "Charlie Poor-Boys" with not > enough extra money for such "luxury" equipment. The best I can say > is that you should "test" UIDE on your systems using SSD disks. If > they "respond" the same as normal hard-disks, including all PCI init > functions, UIDE should "pick them up" and run them O.K. > > If not, only a minor loss, as SSD disks are so fast that they really > should not need caching. You can then run UIDE with its /N1 switch > which causes it to ignore hard-disks but continue to cache diskettes > and CD/DVD drives. They need caching, for they are otherwise SLOW! > > Jack R. Ellis > > > -- > RSA® Conference 2012 > Save $700 by Nov 18 > Register now! > http://p.sf.net/sfu/rsa-sfdev2dev1 > ___ > Freedos-user mailing list > Freedos-user@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/freedos-user > -- http://www.fastmail.fm - Faster than the air-speed velocity of an unladen european swallow -- RSA® Conference 2012 Save $700 by Nov 18 Register now! http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Andrew, You should look for a product called "Disk On Module". They are composed of FLASH chips and are designed to be direct replacements for IDE hard drives. Unlike a lot of CF cards that can be used with an CF to IDE adapter but might not support CHS addressing, DOMs are designed as IDE replacements so they do proper wear leveling and will fully emulate an IDE device, including both CHS and LBA addressing. (A lot of newer CF cards only do LBA addressing.) I replaced a dead 60MB laptop hard drive with a 512MB DOM. It was smaller, takes less power, has more capacity, and has no moving parts. DOMs come in both 40 and 44 pin varieties and range in size from 32MB to 4 or 8GB. Assuming the BIOS of your machine can autodetect hard drives, using a DOM as a replacement for a hard drive should be easy. Some early machines restrict the choice of hard drive by hard coding the BIOS to only accept certain models; those BIOSes need to be patched. But a conventional IDE BIOS should work fine with a DOM. Mike -- RSA® Conference 2012 Save $700 by Nov 18 Register now! http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] FreeDos4Kids (and Kids-at-heart)
Andrew, > I anticipate replacing the dying and clunky old hard-drives for SD > cards on a 44-pin IDE adapter for better performance and improved > efficiency. I imagine that the recent improvements with FreeDOS' > EIDE would facilitate a hardware upgrade like that - am I > understanding that correctly, please? I am the author of the UIDE disk/CD/DVD caching driver, and I assume your reference to "EIDE" is in fact addressing the UIDE driver. I have not tested UIDE with "SSD" disks, nor has anyone commented on such testing. FreeDOS users are often "Charlie Poor-Boys" with not enough extra money for such "luxury" equipment. The best I can say is that you should "test" UIDE on your systems using SSD disks. If they "respond" the same as normal hard-disks, including all PCI init functions, UIDE should "pick them up" and run them O.K. If not, only a minor loss, as SSD disks are so fast that they really should not need caching. You can then run UIDE with its /N1 switch which causes it to ignore hard-disks but continue to cache diskettes and CD/DVD drives. They need caching, for they are otherwise SLOW! Jack R. Ellis -- RSA® Conference 2012 Save $700 by Nov 18 Register now! http://p.sf.net/sfu/rsa-sfdev2dev1 ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
