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#81
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Has your memory card ever worn out?
In article , Floyd L. Davidson
wrote: Any OS that cannot do that is abjectly insecure. There's no correlation between being able to boot and run from read-only media and security. You are clueless. If the boot device is an R/O device, there is no such thing as compromising the booted OS. Think about it... oh yes there is. you won't be able to compromise the contents of the actual read-only drive (and who cares), but you can compromise the *booted* *system* itself once it's up and running. think about it. |
#82
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
In article , Floyd L. Davidson
wrote: Doesn't that make it a bit difficult to add kernel extensions (drivers)? It makes it impossible to durably add anything, since any changes require a write to non-volatile media. That has nothing to do with adding kernel extensions. The in memory kernel is modified by loadable modules. The kernel on disk is not modified at all. and where do those loadable modules go? what's on the read-only disk can't be modified, which means you can't add anything to it. the *only* way you can add an extension or anything else is by writing to a volume, somewhere on the system. |
#83
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
In article , Floyd L. Davidson
wrote: Doesn't that make it a bit difficult to add kernel extensions (drivers)? It makes it impossible to durably add anything, since any changes require a write to non-volatile media. That has nothing to do with adding kernel extensions. The in memory kernel is modified by loadable modules. The kernel on disk is not modified at all. and where do those loadable modules go? what's on the read-only disk can't be modified, which means you can't add anything to it. the *only* way you can add an extension or anything else is by writing to a volume, somewhere on the system. |
#84
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
In article , Floyd L. Davidson
wrote: Pretty hard for the "boot" (system) drive to avoid being written on as the system operates. There is no reason that it needs to be written to. In fact it is very easy to have a system that boots from a DVD! Doesn't that make it a bit difficult to add kernel extensions (drivers)? Drivers and other kernel extensions are linked dynamically in RAM, not on disk (which indeed is the way it was accomplished up through the 1980's). but to add them, you must have a writeable volume. No, you must have a *readable* volume. no, you must have a *writeable* volume. how do you add something to a volume that is only readable? you *can't*. it is *not* possible. there has be a way to *write* the new kernel extensions or whatever else you're adding to the system. |
#85
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
In article , Floyd L. Davidson
wrote: Look at all those distribution "live DVD" disks. They're pretty common. what about them? how many people boot off a live dvd as part of their normal day to day usage? nowhere near as many who boot off a hard drive or ssd. some computers, namely ultrabooks, don't even have dvd drives. sure you could hook one up, but that defeats the point of having an ultrabook. just because something is possible doesn't mean it's commonly done. Look at Android. bad example. android writes back to flash, as does ios. Look at all those millions of WIFI routers. why? embedded devices are single purpose devices and do not have swap space, so they do not count. Sheesh, even the WT-5 wireless from Nikon runs Linux that boots from a read only device. see above regarding embedded devices. So you do admit it is not at all rare! It's easy to do, commonly done, and if security is the most significant issue... it is definitely rare. who boots off a dvd as part of their day to day computer usage? almost nobody. Who boots in day to day computer usage? who said anything about booting every single day? the point is that a typical computer is almost always booted off a hard drive, except in the rare case when a new operating system is being installed to the hard drive from a dvd, and even that is going away since operating systems are now dowloadable, no dvds needed at all. nevertheless, many people do shut down at night and boot in the morning for reasons i don't understand, mainly windows users. I rebooted my computers last week due to an extended power outage. It was the first time in more than a year that any of them had been rebooted. and you no doubt booted off a hard drive, not a dvd. With the single exception of my WIFI router that gets rebooted about once every two weeks. It of course boots from the r/o device you say is so rare as to never be used. you clearly need a better wifi router. anything that needs to be rebooted every two weeks has some serious problems. i have several wifi routers and they all run 24/7 and i don't remember the last time they were rebooted. it's been years. The point still remains that there are multimillions of systems out there being boot *every day* from r/o devices. and multi-billions that aren't. |
#86
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
nospam wrote:
In article , Floyd L. Davidson wrote: enough to burn through some SSDs in short order. If you can afford SSD for swap/paging, you can afford enough RAM to make I/O to swap or paging unnecessary (in many cases). That is true. it's not true. ssd may be more expensive than a similar capacity hard drive, but it's not *that* expensive unless you get really huge capacities. 128-256 gig ssd are very affordable. Not the point - it would be even faster with no backing store at all. A quick google shows 16 GB of DDR3 for roughly $100. I have 4 or 8 GB RAM on this machine, and I never see it use more than 1.5 GB. -- Les Cargill |
#87
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
nospam wrote:
In article , Floyd L. Davidson wrote: enough to burn through some SSDs in short order. If you can afford SSD for swap/paging, you can afford enough RAM to make I/O to swap or paging unnecessary (in many cases). That is true. it's not true. ssd may be more expensive than a similar capacity hard drive, but it's not *that* expensive unless you get really huge capacities. 128-256 gig ssd are very affordable. You say first that it is not true... and then recite exactly that it is in fact true. Logic escapes you? -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#88
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
nospam wrote:
In article , Floyd L. Davidson wrote: Any OS that cannot do that is abjectly insecure. There's no correlation between being able to boot and run from read-only media and security. You are clueless. If the boot device is an R/O device, there is no such thing as compromising the booted OS. Think about it... oh yes there is. you won't be able to compromise the contents of the actual read-only drive (and who cares), but you can compromise the *booted* *system* itself once it's up and running. think about it. That's not the point. The point absolutely was that you can't compromise the booted OS. And that means that if it gets compromised after it is booted the cure is quick and simple: reboot. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#89
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
nospam wrote:
In article , Floyd L. Davidson wrote: Doesn't that make it a bit difficult to add kernel extensions (drivers)? It makes it impossible to durably add anything, since any changes require a write to non-volatile media. That has nothing to do with adding kernel extensions. The in memory kernel is modified by loadable modules. The kernel on disk is not modified at all. and where do those loadable modules go? what's on the read-only disk can't be modified, which means you can't add anything to it. the *only* way you can add an extension or anything else is by writing to a volume, somewhere on the system. You need to learn how it works and stop posting nonsense. The module to be loaded need never appear on a disk assessible to the system. It could, as an example, exist only in RAM and be downloaded via a network. In fact there need not even be an r/o boot device in that sense, because it can be loaded from another system via a network. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#90
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
nospam wrote:
In article , Floyd L. Davidson wrote: Pretty hard for the "boot" (system) drive to avoid being written on as the system operates. There is no reason that it needs to be written to. In fact it is very easy to have a system that boots from a DVD! Doesn't that make it a bit difficult to add kernel extensions (drivers)? Drivers and other kernel extensions are linked dynamically in RAM, not on disk (which indeed is the way it was accomplished up through the 1980's). but to add them, you must have a writeable volume. No, you must have a *readable* volume. no, you must have a *writeable* volume. how do you add something to a volume that is only readable? you *can't*. it is *not* possible. there has be a way to *write* the new kernel extensions or whatever else you're adding to the system. The question was not about adding to the boot volume, it was about adding to the kernel. The kernel, after it is booted, can and typically is modified. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#91
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
nospam wrote:
In article , Floyd L. Davidson wrote: Look at all those distribution "live DVD" disks. They're pretty common. what about them? how many people boot off a live dvd as part of their normal day to day usage? nowhere near as many who boot off a hard drive or ssd. some computers, namely ultrabooks, don't even have dvd drives. sure you could hook one up, but that defeats the point of having an ultrabook. just because something is possible doesn't mean it's commonly done. Look at Android. bad example. android writes back to flash, as does ios. Look at all those millions of WIFI routers. why? embedded devices are single purpose devices and do not have swap space, so they do not count. Sheesh, even the WT-5 wireless from Nikon runs Linux that boots from a read only device. see above regarding embedded devices. So you do admit it is not at all rare! It's easy to do, commonly done, and if security is the most significant issue... it is definitely rare. who boots off a dvd as part of their day to day computer usage? almost nobody. Who boots in day to day computer usage? who said anything about booting every single day? So you admit your point was non-sequitur to begin with. the point is that a typical computer is almost always booted off a hard drive, except in the rare case when a new operating system is being installed to the hard drive from a dvd, and even that is going away since operating systems are now dowloadable, no dvds needed at all. That is true for what *you* do. But it is not necessarily true for what many computers do. The typical firewall does not do that. nevertheless, many people do shut down at night and boot in the morning for reasons i don't understand, mainly windows users. I rebooted my computers last week due to an extended power outage. It was the first time in more than a year that any of them had been rebooted. and you no doubt booted off a hard drive, not a dvd. But that still misses the point. Whether you or I commonly boot our desktops from a hard disk is not the point in question. Note that I did *not* boot my router from a hard disk! With the single exception of my WIFI router that gets rebooted about once every two weeks. It of course boots from the r/o device you say is so rare as to never be used. you clearly need a better wifi router. anything that needs to be rebooted every two weeks has some serious problems. You clearly don't have a clue do you. i have several wifi routers and they all run 24/7 and i don't remember the last time they were rebooted. it's been years. So. That has no significance to the discussion. The point still remains that there are multimillions of systems out there being boot *every day* from r/o devices. and multi-billions that aren't. That has no significance to the discussion. It's is not a question of whether virtually all systems do this or that, or even if most do this or that. Try using a little logic and to be focused on the discussion. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#92
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
nospam wrote:
In article , Floyd L. Davidson wrote: Pretty hard for the "boot" (system) drive to avoid being written on as the system operates. There is no reason that it needs to be written to. In fact it is very easy to have a system that boots from a DVD! Doesn't that make it a bit difficult to add kernel extensions (drivers)? Drivers and other kernel extensions are linked dynamically in RAM, not on disk (which indeed is the way it was accomplished up through the 1980's). but to add them, you must have a writeable volume. No, you must have a *readable* volume. no, you must have a *writeable* volume. how do you add something to a volume that is only readable? you *can't*. it is *not* possible. there has be a way to *write* the new kernel extensions or whatever else you're adding to the system. If I have an os running from a DVD I can load a module into the running kernel from that read only media. I can also remove a module from that running kernel. No writing involved, just reading. I don't know technically how it is achieved, I'm just a thicky builder, but even I can do the loading/unloading modules thing. -- sid RLU 300284 2010.2 |
#93
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
On Sat, 21 Jul 2012 18:10:57 -0400, "Soundhaspriority"
wrote: : : : "Mxsmanic" wrote in message : news : Just out of curiosity, have you ever actually experienced a memory card : failure due to simple wear and tear? : : I know that flash memory allows for only a limited number of write cycles, : but : I'm curious as to how often this limit has actually affected people in : real : life. : : I've never experienced a memory-card failure of any kind [knocking on : wood], : and hopefully I never will, although a simple inability to write to the : card : would probably be less of a disaster than an inability to read what's : written : (apparently wear and tear only impedes writing, but reading still works). : I : always have several cards with me at least, and I try to cycle through : them to : even out the wear and tear. I've been lucky so far. : : Memory cards use NAND flash, which is a very strange medium. When NAND is : used in a memory card, it is written only in large blocks; individual : addressing is not possible in this application. The illusion that a single : address can be rewritten is provided by rewriting the block. : : NAND cells are inherently unreliable. When a block is written, there almost : CERTAINLY will be errors. The user does not see the errors because the block : is written using a very robust error correcting code. : : Nota bene: flash is an unreliable physical device, with clever engineering : used to provide the appearance of a reliable end user device. : : NAND is pattern sensitive to READ disturbance. When cells nearby are read : [sic], it actually disturbs the reliability of the cell, which should, in : theory, be rewritten at intervals. : : Consumer NAND flash now uses MLC (multi-level-cell) architecture, which has : a much shorter lifetime than what used to be the gold-standard, SLC (single : level cell.) SLC is now available only for enterprise apps. The short cell : lifetime is allegedly disguised by wear-leveling algorithms, but when the : block error rate exceeds the ECC capability, and READ disturbances : occur...who knows? : : All this might be too complicated for the microcontroller embedded in a : flash device to handle reliably. With flash, clever engineering created a : problem that isn't simple. But the consumer needs flash. Providing it at a : price the consumer is prepared to pay has resulted in a product that doesn't : fail predictably. Predictable wear out has been replaced by catastrophic : failure, as the rule, rather than the exception. : : In some cases, a memory requirement can be addressed by either flash or hard : drive. In the case of a Sound Devices 744T, I chose to stick with the hard : drive. My personal "feeling", which I can't substantiate with any hard info, : is that some hard drives, selected for both make and particular model, and : handled and mounted to avoid mechanical shock, are more reliable than flash : alternatives. Well, that's an entertaining thought, but hard drives in CF format have been tried. And my recollection (though I never owned one) is that they were expensive and quite fragile. : Bob Morein : (310) 237-6511 I will say this: you've got the nerve to use your real name and even your phone number. Some of the naysayers who have already lined up to tell you off are far too gutless to do that. ;^) Bob |
#94
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
On Tue, 24 Jul 2012 06:07:15 -0700, "William Sommerwerck"
wrote: It's gotten worse as Microsoft increasingly attempts to hide the hard disk's contents from the user. (I want to put things where I think they should go, and be able to find them.) Hear hear! -- Regards, Eric Stevens |
#95
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
"Neil Gould" wrote in message ... Files from audio apps can be very large and get re-written frequently, so it would be difficult, if not impossible to "guarantee" that such operations would not happen, which is why I asked. Al the good programs I have used give you setup options on where to place temp files, data files, backup files, autosave files, multiple scratch disk usage etc. There will always be poorly written programs that don't, your mission is to find something else if you don't like how they behave. Trevor. |
#96
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Floyd L. Davidson writes:
And technically "every swap" does not require physical disk I/O, simply because every program's executable code is *already* available on disk. Swaps typically include all code and data, except for pure procedure code segments that can be shared or reused. So there's always physical I/O. If it *has* available swap it slows to a crawl. If there is no swap it necessarily either crashes or kills off processes. Not in my experience. RAM that is not being used by running processes is typically used for disk cache, and the more that is available the better. That depends on the OS, and on the logical access profile of running processes and the OS. Sometimes disk cache is a waste of memory. Sometimes logical disk I/O must also be physical I/O for reasons of security, and disk cache for large databases with completely random access often have such a low hit ratio that they serve no real purpose. Therefore any program data segments that are never being accessed can and should be paged to the swap device, thus freeing up physical RAM that allows the system to run faster by caching disk reads. Paging and swapping are not quite the same thing. A swap normally involves an entire process. Paging is below the process level and may only involve certain portions of a process. Swapped processes are typically ineligible for dispatch, whereas a process being paged remains eligible for dispatch. Note that that applies only to the data segements, because program code that executes is never put into the swap space to begin with, as it is just directly read in from the already available program binary file. That depends on whether the code is pure procedure or not. Some operating sysems facilitate pure procedure code, some do not. |
#97
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
nospam writes:
In article , Mxsmanic wrote: Precisely! Virtual memory has become almost superfluous with such large address spaces available so cheaply. Backing a 64-bit address space without a swapping or paging file requires 17,179,869,184 gigabytes of RAM, so virtual memory isn't likely to become superfluous any time soon. nonsense. 64 bit address space can address *significantly* more memory than 16 gig, which actually is not that much these days. I do not see your point. As I just pointed out in the post you are backquoting, 64 bits can address 17,179,869,184 gigabytes, which is indeed significantly more than 16. you are going to have swap if you do anything major with your computer, even with that much memory. It depends on the OS design, the process profile, the type of disk access, and so on. |
#98
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
nospam writes:
except, they don't. They are invariably highly active, if they are needed at all. |
#99
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Floyd L. Davidson writes:
That is not true of any modern OS. It is true of every operating system that has more processes than RAM, no matter when it was designed. |
#100
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
nospam writes:
it's not true. ssd may be more expensive than a similar capacity hard drive, but it's not *that* expensive unless you get really huge capacities. 128-256 gig ssd are very affordable. If the system requires substantially more backing store or swap than it has physical RAM, it will run slowly no matter what type of device is used for the backing store or swap. |
#101
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Les Cargill writes:
Not the point - it would be even faster with no backing store at all. Yes. If there is enough RAM to accommodate all running processes without page faults or running out of memory, then the backing store/swap area is not needed, and system performance can be increased by orders of magnitude. |
#102
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
nospam writes:
you absolutely want swap on ssd because it's significantly faster than hd. stop worrying about wearing out ssd. you'll be wanting to replace the computer with a better model long before an ssd wears out. On production systems, you don't replace anything with a "better model" unless the workload changes in a way that is no longer served by the existing model. Replacing SSDs that wear out due to write failure with high physical writes can be prohibitively expensive. |
#103
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Floyd L. Davidson writes:
Perhaps with OS's from MicroSoft, but every other OS can and does do exactly that. All modern operating systems are similar in this respect. |
#104
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Floyd L. Davidson writes:
Mxsmanic wrote: isw writes: Doesn't that make it a bit difficult to add kernel extensions (drivers)? It makes it impossible to durably add anything, since any changes require a write to non-volatile media. That has nothing to do with adding kernel extensions. The in memory kernel is modified by loadable modules. The kernel on disk is not modified at all. Thank you for explaining my point. |
#105
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Floyd L. Davidson writes:
You need to learn how it works and stop posting nonsense. The module to be loaded need never appear on a disk assessible to the system. It is impossible to load a module that is not accessible to the system. It could, as an example, exist only in RAM and be downloaded via a network. In that case, it is accessible to the system, isn't it? Although loading drivers from a network is rather odd. In fact there need not even be an r/o boot device in that sense, because it can be loaded from another system via a network. The network is a read/only boot device. But again, this is quite exceptional for standard desktops (and generally to a lesser extent). |
#106
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Has your memory card ever worn out?
Floyd L. Davidson writes:
Drivers and other kernel extensions are linked dynamically in RAM, not on disk (which indeed is the way it was accomplished up through the 1980's). If there is no non-volatile storage medium available, drivers and extensions that are not compiled into the OS must be reloaded at every boot, QED. |
#107
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Floyd L. Davidson writes:
No, you must have a *readable* volume. If you want to add them across boots, you need a writable, non-volatile device. |
#108
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Floyd L. Davidson writes:
The question was not about adding to the boot volume, it was about adding to the kernel. The kernel, after it is booted, can and typically is modified. Without writable, non-volatile storage media, not only must all drivers and extensions be reloaded at every boot, but the OS must exhaustively poll and discover hardware at every boot, which can take an extremely long time. |
#109
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Floyd L. Davidson writes:
If the boot device is an R/O device, there is no such thing as compromising the booted OS. Think about it... I've actually written operating systems, as opposed to just thinking about them. An operating system can be compromised just as easily when booted from a read-only device as in other cases. Remember, the OS code in memory is not read-only. |
#110
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Floyd L. Davidson writes:
nospam wrote: In article , Floyd L. Davidson oh yes there is. you won't be able to compromise the contents of the actual read-only drive (and who cares), but you can compromise the *booted* *system* itself once it's up and running. think about it. That's not the point. It invalidates your assertion. The point absolutely was that you can't compromise the booted OS. And that means that if it gets compromised after it is booted the cure is quick and simple: reboot. How can it be compromised after it is booted if "you can't compromise the booted OS." These two statements contradict each other. |
#111
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Mxsmanic wrote:
Floyd L. Davidson writes: And technically "every swap" does not require physical disk I/O, simply because every program's executable code is *already* available on disk. Swaps typically include all code and data, except for pure procedure code segments that can be shared or reused. So there's always physical I/O. False. The program code segment is *never* written to a "swap file" on any modern OS. Of course all such segments today can be "shared or reused". So there is not "always physical I/O". If it *has* available swap it slows to a crawl. If there is no swap it necessarily either crashes or kills off processes. Not in my experience. You do not appear to have any experience with kernel code. What else can an OS do if an app requests more memory than exists? It can simply return an error, and in that case any sane program has no choice but to exit. Or the OS can kill some other process to obtain the memory requested. Or it can simply lose sanity, and crash. RAM that is not being used by running processes is typically used for disk cache, and the more that is available the better. That depends on the OS, Yes. And of course modern OS's are the ones being discussed. and on the logical access profile of running processes and the OS. Sometimes disk cache is a waste of memory. Sometimes logical disk I/O must also be physical I/O for reasons of security, and disk cache for large databases with completely random access often have such a low hit ratio that they serve no real purpose. And that is why large databases typically manage their own filesystems, and do not use disk caching. Of course that would be for the database data, not for the program data used by the process as it runs. Therefore any program data segments that are never being accessed can and should be paged to the swap device, thus freeing up physical RAM that allows the system to run faster by caching disk reads. Paging and swapping are not quite the same thing. Gee whiz, Sherlock, nice that you know that. But since nobody said they were, what's yoour point. Regardless of the fact that paging is what is being done, it is still called a swap device. A swap normally involves an entire process. Paging is below the process level and may only involve certain portions of a process. Swapped processes are typically ineligible for dispatch, whereas a process being paged remains eligible for dispatch. The whole point is that most processes have significant code and data that need not be kept in RAM. The data is paged to the swap device, the program code is merely released and marked as available from the original binary file. Note that that applies only to the data segements, because program code that executes is never put into the swap space to begin with, as it is just directly read in from the already available program binary file. That depends on whether the code is pure procedure or not. Some operating sysems facilitate pure procedure code, some do not. We aren't talking about legacy systems or inferior systems. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#112
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Has your memory card ever worn out?
Mxsmanic wrote:
Floyd L. Davidson writes: That is not true of any modern OS. It is true of every operating system that has more processes than RAM, no matter when it was designed. And nobody in their right mind, given the price of RAM today, operates any computer in that manner. I remember folks doing modeling with a Sun 4 workstation back in the late 80's or early 90's, using a 300MB swap device on a system with a whopping 6MB of RAM. The process they ran took about 30 days to complete. Disk space may be cheap, but so is RAM today. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#113
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Has your memory card ever worn out?
Mxsmanic wrote:
Floyd L. Davidson writes: Mxsmanic wrote: isw writes: Doesn't that make it a bit difficult to add kernel extensions (drivers)? It makes it impossible to durably add anything, since any changes require a write to non-volatile media. That has nothing to do with adding kernel extensions. The in memory kernel is modified by loadable modules. The kernel on disk is not modified at all. Thank you for explaining my point. When was that ever *your* point? You never said any such thing, and what you did say did not relate to the discussion! -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#114
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Has your memory card ever worn out?
Mxsmanic wrote:
Floyd L. Davidson writes: Drivers and other kernel extensions are linked dynamically in RAM, not on disk (which indeed is the way it was accomplished up through the 1980's). If there is no non-volatile storage medium available, drivers and extensions that are not compiled into the OS must be reloaded at every boot, QED. So? They need not be on a R/W disk. Typically a modern desktop system might load anything from a dozen to a many dozens of modules at every boot. The machine that I'm writing this article on has 31 kernel modules loaded as I'm writing. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#115
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Has your memory card ever worn out?
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#116
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Has your memory card ever worn out?
Mxsmanic wrote:
Floyd L. Davidson writes: The question was not about adding to the boot volume, it was about adding to the kernel. The kernel, after it is booted, can and typically is modified. Without writable, non-volatile storage media, not only must all drivers and extensions be reloaded at every boot, but the OS must exhaustively poll and discover hardware at every boot, which can take an extremely long time. Bull**** kid. It doesn't take "an extremely long time". In fact auto loading of modules is the norm. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#117
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Has your memory card ever worn out?
Mxsmanic wrote:
Floyd L. Davidson writes: If the boot device is an R/O device, there is no such thing as compromising the booted OS. Think about it... I've actually written operating systems, as opposed to just thinking about them. Then explain why you have so many silly misconceptions about how a real OS works. An operating system can be compromised just as easily when booted from a read-only device as in other cases. Remember, the OS code in memory is not read-only. Oh, really? So just any user can write to it? -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#118
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
Mxsmanic wrote:
Floyd L. Davidson writes: nospam wrote: In article , Floyd L. Davidson oh yes there is. you won't be able to compromise the contents of the actual read-only drive (and who cares), but you can compromise the *booted* *system* itself once it's up and running. think about it. That's not the point. It invalidates your assertion. The point absolutely was that you can't compromise the booted OS. And that means that if it gets compromised after it is booted the cure is quick and simple: reboot. How can it be compromised after it is booted if "you can't compromise the booted OS." These two statements contradict each other. Learn to read and understand what people are saying, and don't twist the meaning of what they say. It's just not indicative of high ethical standards when you do that. -- Floyd L. Davidson http://www.apaflo.com/ Ukpeagvik (Barrow, Alaska) |
#119
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Has your memory card ever worn out?
"Floyd L. Davidson" wrote in message
... Mrs wrote: Floyd L. Davidson writes: If the boot device is an R/O device, there is no such thing as compromising the booted OS. Think about it... I've actually written operating systems, as opposed to just thinking about them. Then explain why you have so many silly misconceptions about how a real OS works. Tony the Troll (aka Mrs. Maniac) loves to troll by spewing **** about subject of which he has no knowledge. His head is permanently stuck in his asshole. You'll never get a rational discussion with this particular semi-human vermin. |
#120
Posted to rec.video.desktop,rec.photo.digital,rec.audio.pro
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Has your memory card ever worn out?
"Floyd L. Davidson" wrote in message
... Mrs wrote: Floyd L. Davidson writes: nospam wrote: In article , Floyd L. Davidson oh yes there is. you won't be able to compromise the contents of the actual read-only drive (and who cares), but you can compromise the *booted* *system* itself once it's up and running. think about it. That's not the point. It invalidates your assertion. The point absolutely was that you can't compromise the booted OS. And that means that if it gets compromised after it is booted the cure is quick and simple: reboot. How can it be compromised after it is booted if "you can't compromise the booted OS." These two statements contradict each other. Learn to read and understand what people are saying, and don't twist the meaning of what they say. It's just not indicative of high ethical standards when you do that. Mrs Maniac (Anthony ****head) has no moral or ethical standards. |
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