Re: swap not a substitute for virtual memory
For what it is worth, after I removed /usr/bin/metalayer-crawler, my system went from being completely unusable for anything but being a broken alarm clock to being relatively useful. metalayer-crawler's generally only a system-hog at bootup, so shouldn't cause many problems unless you completely shut down and reboot your device rather than just suspending it. I must admit to being surprised how badly it slows the system down, since according to the init file, it apparently should be running with a niceness of 19, so should pretty much only get CPU time when nothing else requires it. The only other time I've found it kicks in is on the odd occasion I've copied large number of files onto the device, but apart from that it never gives me any hassle except if I want to use my device straight after booting. -- Tony Green Ipswich, Suffolk, England http://www.beermad.org.uk http://no2id-ip.web-brewer.co.uk ** This message is digitally signed. If your email client is unable to read digital signatures, you may see an attachment that you cannot open. See http://www.gnupg.org/(en)/documentation/faqs.html for more information. You can validate my PGP key from my website: http://www.beermad.org.uk/ * No Micro$oft products were used in the generation of this communication -- Tony Green Ipswich, Suffolk, England http://www.beermad.org.uk http://no2id-ip.web-brewer.co.uk ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
Re: swap not a substitute for virtual memory
On Thu, Apr 17, 2008 at 04:13:54PM +0100, Tony Green wrote: For what it is worth, after I removed /usr/bin/metalayer-crawler, my system went from being completely unusable for anything but being a broken alarm clock to being relatively useful. metalayer-crawler's generally only a system-hog at bootup, so shouldn't cause many problems unless you completely shut down and reboot your device rather than just suspending it. I must admit to being surprised how badly it slows the system down, since according to the init file, it apparently should be running with a niceness of 19, so should pretty much only get CPU time when nothing else requires it. Perhaps it should be ionice'd as well? Heavy I/O may hog the system down even if the process is niced. What I/O scheduler does Maemo use? ionice only works with CFQ. Marius Gedminas -- IBM motto: If you can't read our assembly language, you must be borderline dyslexic, and we don't want you to mess with it anyway -- Linus Torvalds signature.asc Description: Digital signature ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
Re: swap not a substitute for virtual memory
The subject line is incorrect. Swap is the portion of virtual memory which is not physical. What you should have said is swap not a substitute for *physical* memory. -- Allen Brown http://brown.armoredpenguin.com/~abrown At Wed, 16 Apr 2008 13:18:29 -0400, Ian Lawrence wrote: Hi, The issue is more that the whole Web 2.0 hasn't been planned to be run in 64MB of RAM. There are sites out there where a single Flash object or JavaScript script consumes more memory. Even 128MB is tight. But, I mean it is possible to increase the amount of memory available for a 770 using an MMC card, right?. I am not sure what the upper limit is but 128MB + 64MB of system memory seems feasible. You are confused about what swap is. Swap allows the memory manager to page (save) anonymous memory to backing store (which in this case is your disk). If union of the working set of the active applications (the memory they need to run with only a trivial amount of faults, i.e., page-ins) exceeds the amount of *RAM*, then your system thrashes. As disk is several orders of magnitude slower than RAM, in such a case, your system makes no useful progress and will appear to you to have frozen. The advantage of swap then, is that if you are running e.g. Mozilla and its working set is large, then the memory manager can page the anonymous memory of background applications (as well as the anonymous memory that Mozilla uses, which is hopefully inactive). Without swap, the only data that the memory manager can page is that associated with files. So, program and library text, data files, etc. The problem is that most programs don't use the disk format for the data they use: on bringing it into memory, they convert it to a form useful for in-memory operations. Thus, a lot of the memory on your system will be occupied by such computed data, which, without swap, is locked in memory until it is explicitly freed. For what it is worth, after I removed /usr/bin/metalayer-crawler, my system went from being completely unusable for anything but being a broken alarm clock to being relatively useful. ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
Re: swap not a substitute for virtual memory
At Thu, 17 Apr 2008 11:02:53 -0700 (PDT), Allen Brown wrote: The subject line is incorrect. Swap is the portion of virtual memory which is not physical. What you should have said is swap not a substitute for *physical* memory. Yes. ___ maemo-developers mailing list maemo-developers@maemo.org https://lists.maemo.org/mailman/listinfo/maemo-developers
