September 2008 - Darwin-dev

Re: Memory management and mmap
by Michael Smith 05 Sep '08

05 Sep '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Sep 4, 2008, at 5:15 PM, darwin-dev-request(a)lists.apple.com wrote: Or perhaps someone has a better memory management system in mind? = Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… I'm developing an app that must handle thousands of image thumbnails. Obviously I need some method of handling all these thumbnails in memory. I'm building this app for Tiger so I can't use any spiffy Leopard features. It is my understanding that 32-bit apps cannot address more than 4 GB of virtual memory. Right now our app simply keeps these thumbnails in a backing store file, and as thumbnails are displayed, their respective chunk is mmap'd into memory from the backing store file. (We're mmap'ing instead of simply reading from the file to decrease loading times, so the thumbnail data is read lazily on a need basis). Here lies our problem: if too many photos are imported, there won't be enough virtual memory to handle all the thumbnail data, and the app will crash. Actually, your problem is that you think that by using mmap, you will get better performance than if you read the thumbnails explicitly. It's understandable why you might think this, but it's not correct. In your case, you have a better idea than the VM does about what thumbnails you are (and aren't) going to need in the immediate future, and you know better than the VM what data in the file translates to those bitmaps. So I need a way to cap how much of the thumbnail backing store file is kept in memory. Not really; what you need to do is implement your own thumbnail pager. There is no way for you to hint the VM such that it will do a better job than you can do by paging thumbnails yourself. mmap() is a convenient way of avoiding doing work in some general cases. Your workload isn't one of them, I'm sorry. This email sent to site_archiver(a)lists.apple.com

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Re: Darwin / OSX USB sniffer source?
by Jonas Maebe 05 Sep '08

05 Sep '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On 05 Sep 2008, at 01:47, John Zorko wrote: Jonas _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… I'm interested in sniffing the USB communications between my Mac and various devices connected to it. Is there source (even if in basic "example" form) that demonstrates USB sniffing on Darwin / OSX? /Developer/Applications/Utilities/USB Prober.app (when you install the developer tools). This email sent to site_archiver(a)lists.apple.com

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Darwin / OSX USB sniffer source?
by John Zorko 05 Sep '08

05 Sep '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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Re: hanging bluetooth driver? (well, user progs opening it)
by Eli Bach 05 Sep '08

05 Sep '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:from:to :in-reply-to:content-type:content-transfer-encoding:mime-version :subject:date:references:x-mailer; bh=8Fu1ZHDtDVwAZGaduPHNxpOn2mvuHFAxgXIV+A6DxoI=; b=kiWan3UezPwmAnHRlxfo8QY7oOYpGST7pm+LdN/y8FXhVLWsXAOjvc7Eh4wRLfDZZ6 nqdHLd7u7u/mDhXJ8xAeledZdqONB+JFJfmHgfae6WazHLrhC/e8VdwHI5i9QabugTx5 bSlWK7lb7dUPmXMRNPIXT87nYCNIpieKKei0A= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:from:to:in-reply-to:content-type :content-transfer-encoding:mime-version:subject:date:references :x-mailer; b=BUxuPxwQg8cLdCPOJNYTEg5xLObcRWVUIm4UupIrPry7IjvfHgaY5rlmaSLH650m++ 2Uy5bJgKgOf3aY7SqhUtnks93PD4+5L/Ncqou83IauaZj7X+iKEQMEDrfV/dWnlT4AU8 1iiTTkGDa+cq/Y8nEYCiiIyleG4QYPqIc8YtI= On Sep 4, 2008, at 5:15 PM, Brad Parker wrote: The only way I have found to clear this state is to reboot. Any ideas? Any way to kill the zombie? _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… I have not tried this in 10.5, but I will at some point. You could try turning BlueTooth off, then back on again in System Preferences. This email sent to site_archiver(a)lists.apple.com

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hanging bluetooth driver? (well, user progs opening it)
by Brad Parker 05 Sep '08

05 Sep '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Organization: Heeltoe Consulting Thought I bounce this off people here: I'm running 10.4.11 on a 64 bit ppc imac. I recently connected a bluetooth serial port. It associates and creates several /dev/cu.xxx and /dev/tty.xxx device nodes. It sort of works ok, but after a while the user process accessing it hangs. (it's running, ahem, zmodem; what can I say) I try and kill the user process and it does not die. The zombie is left in state 'E' according to ps, which is "trying to exit". I assume, basedc on some unixy notions, that a driver is sleeping in some uninterpretable way on the close or maybe last write or read. I would, however, assume that if I turned off bluetooth the proc would exit, but it does not. Also, if another proc opens the /dev/ node, when this zombie is present, it also hangs and can not be killed. It hangs in 'U', which is (surprise) uninterruptable wait. I thought we got ride of uninterruptable sleeps in serial ports in the early '90s :-) The only way I have found to clear this state is to reboot. Any ideas? Any way to kill the zombie? I have not tried this in 10.5, but I will at some point. -brad _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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Re: calling select, via syscall, on 64 bit Leopard. (solved)
by Jean-Daniel Dupas 03 Sep '08

03 Sep '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Le 3 sept. 08 à 14:01, Luke Daley a écrit : Again, when in doubt, RTFM (when will I learn?)… http://developer.apple.com/documentation/DeveloperTools/Conceptual/DynamicL… _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… I was able to get this to work by using the method outlined in that article (i.e. using dlsym()) and avoiding syscall() altogether. Thanks to everyone who helped out. Yep, you right, using dlsym(RTLD_NEXT, "symbol"); is probably a better solution than the one I provided. It is part of the public API and it is supported ;-) This email sent to site_archiver(a)lists.apple.com

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Re: calling select, via syscall, on 64 bit Leopard. (solved)
by Luke Daley 03 Sep '08

03 Sep '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Again, when in doubt, RTFM (when will I learn?)… http://developer.apple.com/documentation/DeveloperTools/Conceptual/DynamicL… Thanks to everyone who helped out. -- LD. _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… I was able to get this to work by using the method outlined in that article (i.e. using dlsym()) and avoiding syscall() altogether. This email sent to site_archiver(a)lists.apple.com

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Re: calling select, via syscall, on 64 bit Leopard.
by Jean-Daniel Dupas 03 Sep '08

03 Sep '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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calling select, via syscall, on 64 bit Leopard.
by Luke Daley 03 Sep '08

03 Sep '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Hi, #include <libc.h> #include <mach-o/nlist.h> typedef int (*__syscall_t)(quad_t number, ...); return 0; } Looking at mach-o/nlist.h… struct nlist { union { #ifndef __LP64__ char *n_name; /* for use when in-core */ #endif int32_t n_strx; /* index into the string table */ } n_un; uint8_t n_type; /* type flag, see below */ uint8_t n_sect; /* section number or NO_SECT */ int16_t n_desc; /* see <mach-o/stab.h> */ uint32_t n_value; /* value of this symbol (or stab offset) */ }; That looks to me line n_name isn't there on 64 bit architectures. Can I get at this any other way? -- LD. _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This was the select and svn discussion, but we have narrowed the problem down to syscall() on 64 bit Leopard so I am starting a new thread. `man syscall` tells us that you need to use __syscall() on 64 bit architectures. The problem with that though is that __syscall() is in libSystem, but is not exported. Jean-Daniel Dupas then contributed this code to get to __syscall()… int main(int argc, const char * argv[]) { struct nlist nl[1]; bzero(&nl, sizeof(struct nlist) * 2); nl[0].n_un.n_name = (char *)"___syscall"; if (nlist("/usr/lib/libSystem.dylib", nl) < 0 || nl[0].n_type == N_UNDF) { fprintf(stderr, "nlist(%s, %s) failed\n", "/usr/lib/libSystem.dylib", nl[0].n_un.n_name); return -1; } __syscall_t fcn = (__syscall_t)nl[0].n_value; Except that gives "error: ‘union <anonymous>’ has no member named ‘n_name’". This email sent to site_archiver(a)lists.apple.com

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Re: Safe Boot with Local-Root driver on Leopard?
by Duane Murphy 03 Sep '08

03 Sep '08

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Thanks Soren, - --- At Tue, 2 Sep 2008 14:19:57 -0700, Soren Spies wrote: > >On Aug 29, 2008, at 20:28, Duane Murphy wrote: > >> I did some more testing and I think it's not the kext, but rather >> that I >> am safe booting on a boot!=root disk. > >Yeah, there are some known issues with Safe Boot and Boot!=Root. :( <rdar://problem/6191789> ...Duane -----BEGIN PGP SIGNATURE----- Version: PGP Desktop 9.8.3 (Build 4028) Charset: ISO-8859-1 wsBVAwUBSL3qb0rg9acQ4r2CAQh4ZggA5wSlh1uJiaSO+J2/HUvK8rN2xVy3xuc6 ka6kKAa91Sl6uYqfv9ufuwHPOg8Y8xze376a8xqnr2l+BhEy5n48h7qs5k/Jss1u 7FobYoA8VL2T+Wpyy70s6KiDlzFC8bC5nt+qBwpMdsnDZPLeDh3Rn1kEpcY/AnF0 KqldD/SKfBIe4wn9LuDD6waETIxTzCdLA7V85+aTF6JvJf7OL6fohOClBV1Km8Iy 5SkvKi1YN1FlsJCbdrpH832jT8aIpeHe9xr45+ByCiHVpbQSivm1CNJSkDekfnUZ 8vP35LU99QmvwGXzLDWO2U1M+/pYWvoeSzZ0kSFwETzokfUJTEYhSw== =uTth -----END PGP SIGNATURE----- _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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