Jihad needs scientists
in [Design]
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From: Eeyore on 25 Feb 2007 12:53 Ken Smith wrote: > <jmfbahciv(a)aol.com> wrote: > > kensmith(a)green.rahul.net (Ken Smith) wrote: > >> <jmfbahciv(a)aol.com> wrote: > >> > >>>VM isn't swapping. VM allows the OS to manage smaller chunks > >>>of memory rather than segments. > >> > >>That is completely and totally worng. "Virtual memory" means quite > >>literally "memory that is not real". > > > >No. It is memory whose addressing is larger than available physical > >memory. > > No, not only the addressing appears larger. The total memory appears to > be more. Merely allowing an address space that is larger is merely > address translation. You only get into virtual memory when it appears the > programs as though the machine has more memory than there is physical RAM. > This is exactly what I was telling you when I directed you to how the word > "virtual" is defined. To the processor itself the VM should be transparent. It should 'look' and behave like acres of RAM. A good example of where the such a task should be offloaded from the CPU itself. Graham
From: Ken Smith on 25 Feb 2007 12:59 In article <ers3rf$8qk_001(a)s1016.apx1.sbo.ma.dialup.rcn.com>, <jmfbahciv(a)aol.com> wrote: >In article <erpov3$c02$3(a)blue.rahul.net>, > kensmith(a)green.rahul.net (Ken Smith) wrote: [.....] >>You are assuming that I don't know about things I don't care about this is >>a serious error on your part. I know that there are many people out there >>who have not yet seen the light and still run Windows. I know that these >>people are doomed to lose valuable data at some time in the future. I >>know that fixing this will require some software that gets around things >>Windows does. I don't run Windows. I run Linux. As a result, I want to >>back up my data on a Linux box. I also want to protect my self from the >>bad effects of Windows losing data on someone else's machine. This is why >>I raise the issue. > >And you keep assuming, erroneously, that this type of usage is the >majority of computing in the world. It is not. Yes, it is. Look at how many homes have PCs in them today. This is the big market for computers today. It massively out weights the business usage. > I am trying to >talk about the day when everybody has to have a computer to do any >financial transactions. You are changing the subject to the future. In fact your transactions do require a computer. It is the one at the bank and not yours however. >>Either, you just lack imagination about what an evil person can do or you >>over estimate the problem caused by something like a lightning strike. An >>evil person can destroy any copy on any machine he has the ability to >>write to. This means that he can delete all the data on the remote >>machines too. This is why you need a write only memory in the system. > >This subject is too complex to discuss without some basic computing >knowledge. You don't seem to have that specialized knowledge. I've >spent man-years on these kinds of problems. You are attempting to get out of discussing an issue because you know that you have already made enough errors in the area to discredit everything you say. You claim a lot of knowledge. Your knowledge is from a very narrow base. You also claim to have spent "man years" this doesn't mean you got it right or even that you know anything. It just means you spent a lot of time. [....] >>>YOu seem to be talking about a bit-to-bit copy. That will also >>>copy errors which don't exist on the output device. >> >>I am talking of a complete and total and correct image of the drive. > >I know you are. A complete and total and correct image of the >drive will also include its bad spots. It is possible (and >likely) that the reason you are rebuilding your system is becaues >a bad spot happened on a crucial point of the file system. The >you are describing will simply restore the problem that wiped >out your disk. It does the restore. The repair is another issue. Putting the system back as it was in the first step. >> It >>is a bit by bit copy. Usually it is stored onto a larger drive without >>compression. If something goes bad, you can "loop back and mount" the >>image. This gives you a read only exact copy of the file system as it >>was. You then can simply fix the damaged file system. > >Now go back to my reply ^up there^. You have a flaw in your >backup strategy. No, I don't. You have confused doing a repair with doing a restore. The restore method I suggested is correct. If you now want to discuss the new topic of repair, then we can begin that topic. >>>>No great amount of care is needed. I've done that sort of restore a few >>>>times with no great trouble. Since files are stored with the modification >>>>date, a copy command that checks dates does the hard part. >>> >>>You are very inexperience w.r.t. this computing task. >> >>You seem to be claiming knowledge you don't have. > >I am not claiming; it is a fact that I have the knowledge..and >extensive work experience. You have also made claims about hardware issues, that are easy to prove to be false. [....] >>It in fact can be easier. I knew someone who wrote a lot of the software >>used by banks and insurance companies. They stored the data transaction >>by transaction, daily and incrementals, monthly near full backups and >>yearly total backups. The system for recovery was very well tested and >>automated. After every software change, they had to requalify the code. >>This meant restoring an old back up and making a new one and restoring >>that. I assume that software like that is still the common practice. > >It's even more complicated. I yak daily with a guy who does this work. I doubt that it has become seriously more complex. The issues all existed at that time. The amount of data is all that has increased not the complexity of the question. [....] >>It doesn't matter if you bank on line or in person. If you bank's >>computers fail, you can't do a transaction. If they lose all their >>computer data, you will have a devil of a time getting at your money. >>This is why I always try to keep more than one bank, a couple of credit >>cards and some cash. I know that there is some risk that a bank may have >>a windows machine connected to the important information. > >Your backup strategy for this type of computing is mulitple copies. Yes, muliple copies of the data in one form or another is what you need. The information must be stored more than once if you expect to be able to put back the data that has been lost. There is no way around this. Error correcting codes are just ways of storing the information more than once so even the storage systems and modern RAM chips do this. >Most people don't have enough money to maintain multiple accounts. Most people can do it. You don't need to put a lot of money into a bank to have an account there. With most banks, just having had an account for a while will get you some form of loan on just your say so. Overdraft protection is the common loan situation. >Most people don't check their single account activity; having >many accounts will not solve this problem but mutiply instances >of it. It protects against the mere failure of the bank's computer. This can strand you. > To use your stategy, you have to keep up with your backup >maintenance for many accounts rather than one. Every bank's timing >is different. This is not a solution. It solves the problem of failure. Evil activity is solved by checking the balances etc. There are two problems that must be covered. You ignore one and don't assume I've already thought of how to solve the other. -- -- kensmith(a)rahul.net forging knowledge
From: Eeyore on 25 Feb 2007 13:01 Ken Smith wrote: > Eeyore <rabbitsfriendsandrelations(a)hotmail.com> wrote: > >jmfbahciv(a)aol.com wrote: > > > >> Doesn't it bother you that electronic checks can be applied against > >> your account without any physical permission written by you? > > > >You mean a debit ? > > > >I could hardly live without it. > > Even if you did try, at the bank the check causes an electronic transfer > of money. These days, the checks don't travel. It has been a long time > since physical money went from bank to bank in reaction to a check. Back in 1971 when I opened my first bank account, they still posted you the paid cheques. That soon disappeared. Electronic debits are invaluable. I just signed up to a telecoms provider whose call charges are insanely cheap. They won't accept cheques and stuff. It all has to be done electronically. http://www.call1899.co.uk/index2.php# I'm still having some trouble believing this. Landline calls inside the UK are 4 pence regardless of duration ! Calling the USA / Canada / France / Germany / Singapore even ! costs 1p per minute plus 4p connection charge. Graham
From: Ken Smith on 25 Feb 2007 13:12 In article <45E1CD23.26249F55(a)hotmail.com>, Eeyore <rabbitsfriendsandrelations(a)hotmail.com> wrote: [....] >> No, not only the addressing appears larger. The total memory appears to >> be more. Merely allowing an address space that is larger is merely >> address translation. You only get into virtual memory when it appears the >> programs as though the machine has more memory than there is physical RAM. >> This is exactly what I was telling you when I directed you to how the word >> "virtual" is defined. > >To the processor itself the VM should be transparent. It should 'look' and >behave like acres of RAM. A good example of where the such a task should be >offloaded from the CPU itself. No, that isn't done. VM systems are also usually multitaskers. You could create one that isn't but the rule is that they are. Here's how it the operation breaks down in a multitask environment. - Running Task A - Task A does a page fault on the real memory - OS gets an interrupt - Perhaps some checking is done here - OS looks for the page to swap out - Complex issue of priority on swapping skipped here. - OS marks the outgoing page to be not usable - OS starts swap actions going - OS looks for a task that can run now - OS remembers some stuff about task priorities - OS switches to new context - Task B runs - Swap action completes - OS gets interrupt - OS marks the new page as ready to go - OS checks the task priority information - OS maybe switches tasks - Task A or B runs depending on what OS decided. This way, a lower priority task can do useful stuff while we wait for the pages to swap. -- -- kensmith(a)rahul.net forging knowledge
From: Dirk Bruere at NeoPax on 25 Feb 2007 13:31
Eeyore wrote: > > Ken Smith wrote: > >> Eeyore <rabbitsfriendsandrelations(a)hotmail.com> wrote: >>> jmfbahciv(a)aol.com wrote: >>> >>>> Doesn't it bother you that electronic checks can be applied against >>>> your account without any physical permission written by you? >>> You mean a debit ? >>> >>> I could hardly live without it. >> Even if you did try, at the bank the check causes an electronic transfer >> of money. These days, the checks don't travel. It has been a long time >> since physical money went from bank to bank in reaction to a check. > > Back in 1971 when I opened my first bank account, they still posted you the paid > cheques. That soon disappeared. > > Electronic debits are invaluable. I just signed up to a telecoms provider whose > call charges are insanely cheap. They won't accept cheques and stuff. It all has > to be done electronically. > > http://www.call1899.co.uk/index2.php# > > I'm still having some trouble believing this. Landline calls inside the UK are 4 > pence regardless of duration ! Calling the USA / Canada / France / Germany / > Singapore even ! costs 1p per minute plus 4p connection charge. > > Graham > I use Skype for all international and local calling these days. 1.2p anywhere. It's esp valuable for business calling those 800 numbers in the US - they're free. -- Dirk http://www.onetribe.me.uk - The UK's only occult talk show Presented by Dirk Bruere and Marc Power on ResonanceFM 104.4 http://www.resonancefm.com |