From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 11174e,acfad2f7f67e34e3,start X-Google-Attributes: gid11174e,public X-Google-Thread: 103376,19140af19dfa6e01 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2003-09-23 18:46:49 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!newsmi-us.news.garr.it!NewsITBone-GARR!news.mailgate.org!newsfeed.stueberl.de!fu-berlin.de!uni-berlin.de!82-43-33-75.cable.ubr01.croy.blueyonder.co.UK!not-for-mail From: "Nick Roberts" Newsgroups: comp.lang.ada,alt.os.development Subject: Re: Ada 0Y plans for garbage collection? Date: Wed, 24 Sep 2003 02:46:44 +0100 Message-ID: References: <1127954.kcBZz6amlf@linux1.krischik.com> <3F60E747.40805@attbi.com> <1557617.vUiuI5kIPQ@linux1.krischik.com> <3F6F1A93.50709@attbi.com> <2q30nv4fain641rin9dia3onjr7ut01our@4ax.com> NNTP-Posting-Host: 82-43-33-75.cable.ubr01.croy.blueyonder.co.uk (82.43.33.75) X-Trace: news.uni-berlin.de 1064368008 4161659 82.43.33.75 (16 [25716]) X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 5.50.4807.1700 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4807.1700 Xref: archiver1.google.com comp.lang.ada:42832 alt.os.development:38675 Date: 2003-09-24T02:46:44+01:00 List-Id: "Dmitry A. Kazakov" wrote in message news:2q30nv4fain641rin9dia3onjr7ut01our@4ax.com... [re booting and sleeping] > Yep. Especially interesting it becomes with plug'n'play devices. You > have, say a USB or PCMCIA device attached, before your Windoze > hibernates. While it peacefully sleeps, you archly eject the hardware > and then wake it up! The effect might be amazing, though predictable > ... > Of course in a truly memory-mapped OS, the present concept of > hardware drives is out of place. One more reason for Ada OS? I think the broad scheme I would like to adopt for AdaOS would be as follows. Each device driver, having at least once gone through a complete hardware configuration procedure, would record the hardware configuration upon shutdown. Upon the next reboot, the device driver would reinstate this configuration, and would perform a quick check that the configuration still accords with the detectable hardware (if this check failed, the full configuration procedure would be activated). With a bit of care, this technique should make it possible to fully shutdown and then reboot very rapidly, but it would still be safe in the case of intervening hardware changes (which would automatically cause reconfiguration). I intend to design the user application software for AdaOS so that it (normally) remembers its important state in between the user logging off and back on again. This is primarily to encourage users to log off whenever they leave the workstation, but it also means that a user can log off, shutdown, reboot, and log on, and all (or most) of their work (open windows) will be reinstated as it was when the user logged off. I don't know why operating systems (Windows, SunOS, and Linux in my direct experience) are so slow at booting up, but I suspect it has a lot to do with device drivers intialising themselves and their hardware. If this initialisation can be either avoided (by the above tactics) or deferred (to be done in the background after the boot procedure has got the system to a usable stage), the user will perceive a fast boot process. If the user can shutdown and reboot quickly (within a few seconds, I suppose), and does not have to go through the rigmarole of closing a lot of programs (windows) and then restarting them, I suspect the demand for a 'sleep mode' would be largely obviated. If any OS is to be really secure, it must be basically reliable. I think Dmitry has neatly illustrated the dangers of such fundamental complications as sleep modes and other forms of partial shutdown. If a machine supports a sleep mode, I think that's okay (especially as part of an overall power management regime), but a full shutdown is better. However, I'm open to debate! -- Nick Roberts Jabber: debater@charente.de [ICQ: 159718630] [CROSS POSTED! Please ensure replies go only to alt.os.development - thanks.]