July 2005 - Darwin-dev - lists.apple.com

Re: Why does free() take 1,100 microseconds?
by neal olander 26 Jul '05

26 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Thanks for the suggestion. I suppose my question could be re-worded as: Or, is there a way for me to get access to the free() source code? _______________________________________________ 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've already run the Shark profiler on the application. I've pinpointed the slowness down to the free() function ... but I cant get details inside that. I'm posting to Darwin-dev rather than optimization because I figured that Darwin-dev peopole might have more insight into the internal operations of free(). What could free() be doing that could possibly take 1,100 microseconds, and is there any thing I can do to reduce that time? This email sent to site_archiver(a)lists.apple.com

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Re: Why does free() take 1,100 microseconds?
by Garth Cummings 26 Jul '05

26 Jul '05

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 smime.p7s

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Why does free() take 1,100 microseconds?
by neal olander 26 Jul '05

26 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com This single call to free() takes about 1,100 microseconds. Any suggestions would be appreciated! Thanks in advance! _______________________________________________ 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've got a time critical application that must run very, very fast. The application is written in C++ with Project Builder, running on MacOSX. The application runs fine, but there is a speed bottleneck I have: I've traced it down to a single call to free() which is freeing a memory buffer (approx 1 MB) that was earlier allocated with malloc(). A normal call to free() takes around 5 to 50 microseconds ... I've timed them in several test programs on the Mac and Windows. Even the other calls to free() within this program run fast. Does anyone have any suggestions why this one call to free might be taking so long? I need to get this call to free() to run much faster. The only clue I have is that this memory buffer has been heavily used (lots of reading and writing) and also this application is rather large (500 MB Vsize virtual memory) so I'm sure that virtual memory is getting paged in and out. I'm unable to get inside the free() call in the debugger, so I have no idea what it is doing inside that takes so long. There is no simple way to re-design the program to avoid the free(): I need to repeately allocate and free memory buffers, each of a variable size (and there is no way to predict ahead of time the sizes, even the maximum size). This email sent to site_archiver(a)lists.apple.com

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Re: Talking to MySQL from C
by Michael Maibaum 26 Jul '05

26 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com 26 jul 2005 kl. 10.21 skrev Mark Gilbert: Or just use PostgreSQL <http://www.postgresql.org/about/licence> see, nice, friendly licence. _______________________________________________ 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… On 26 Jul 2005, at 10:55, Pelle Johansson wrote: Other people have answered your question from a technical perspective, but also be aware that linking with the MySQL client library may impose licensing requirements (i.e. require you to GPL your application). I guess an option would be to create and open source an intermediate daemon application to run alongside my commercial app interfacing a generic query from my app with the MySQL C- library. Does anyone know if this type of thing exists already ? Apache and php... Notice that you're entering a gray area with regards to what constitutes linking and what is application i/o. If it is an opensource application but it's pretty much useless to everything but your commercial one I believe the FSF considers that to be linking even if there's no sharing of address space. This email sent to site_archiver(a)lists.apple.com

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Re: Talking to MySQL from C
by Pelle Johansson 26 Jul '05

26 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com 26 jul 2005 kl. 10.21 skrev Mark Gilbert: -- Finlay This is an interesting point. Apple uses the GPL as licence. _______________________________________________ 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… Other people have answered your question from a technical perspective, but also be aware that linking with the MySQL client library may impose licensing requirements (i.e. require you to GPL your application). Not completely true. MySQL has added an exception for some other opensource licences, even if incompatible with the GPL. My app is a commercial product - and would assume that the user will be connecting to MySQL pre-installed on Mac OSX Server (which presumably Apple have a license for ?) I guess an option would be to create and open source an intermediate daemon application to run alongside my commercial app interfacing a generic query from my app with the MySQL C-library. Does anyone know if this type of thing exists already ? Apache and php... Notice that you're entering a gray area with regards to what constitutes linking and what is application i/o. If it is an opensource application but it's pretty much useless to everything but your commercial one I believe the FSF considers that to be linking even if there's no sharing of address space. -- Pelle Johansson <morth(a)morth.org> This email sent to site_archiver(a)lists.apple.com

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Re: Talking to MySQL from C
by Mark Gilbert 26 Jul '05

26 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Folks. I am trying to write a very simple database client application in C which will connect to a MySQL server on OSXServer. Other people have answered your question from a technical perspective, but also be aware that linking with the MySQL client library may impose licensing requirements (i.e. require you to GPL your application). This is an interesting point. if this is too off-topic, perhaps someone could advise a more appropriate forum Cheers Mark -- mark(a)gallery.co.uk Tel: +44 208 340 5677 fax: +44 870 055 7790 http://www.gallery.co.uk New Product ! - Zen MetaCorder Location Sound Field Recorder http://www.metacorder.info _______________________________________________ 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… On 7/25/05, Mark Gilbert <mark(a)gallery.co.uk> wrote: -- Finlay My app is a commercial product - and would assume that the user will be connecting to MySQL pre-installed on Mac OSX Server (which presumably Apple have a license for ?) I guess an option would be to create and open source an intermediate daemon application to run alongside my commercial app interfacing a generic query from my app with the MySQL C-library. Does anyone know if this type of thing exists already ? This email sent to site_archiver(a)lists.apple.com

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Re: Talking to MySQL from C
by plumber 26 Jul '05

26 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com about mysql license http://www.mysql.com/search/?q=license&charset=iso-8859-1 -----BEGIN PLUMBER CODE BLOCK----- Version: 1.0 ¬ | | > Regards Plumber || GNU Darwin. ¬ \\\ plumber.gnu-darwin.org ¬ ¬ | | > OOP --\///\ (0)=(0) Darwin/Power Mac G4. ¬ | | > ( __ò ó__ ) The best for Fede ¬ \\\ federicafontana.it ¬ ------END PLUMBER CODE BLOCK------ -----BEGIN GEEK CODE BLOCK----- Version: 3.1 GMU/S d+@ s: a- K+++++ PGP++++ K---- dpu s--:-- C++++ C-- B L X U++++ P+++ C-- P! L--- E+++ W+++ P! L--- N+++ o-- K+++++ ------END GEEK CODE BLOCK------ Plain, Loving, Useful, Mischievous, Brutal, Explosive, Responsible _______________________________________________ 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"It's making my eyes better. And it's legal. I could walk up to the President and blow smoke in his stupid monkey face, and he'd just have to sit there groovin' on it!" Homer J Simpson, Springfield, Illinois, Massachusetts nobody knows :) This email sent to site_archiver(a)lists.apple.com

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Re: Talking to MySQL from C
by plumber 26 Jul '05

26 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Hi there, aka outlaw :) How are you ? i hope so fine Best R(crypted)ds -----BEGIN PLUMBER CODE BLOCK----- Version: 1.0 ¬ | | > Regards Plumber || GNU Darwin. ¬ \\\ plumber.gnu-darwin.org ¬ ¬ | | > OOP --\///\ (0)=(0) Darwin/Power Mac G4. ¬ | | > ( __ò ó__ ) The best for Fede ¬ \\\ federicafontana.it ¬ ------END PLUMBER CODE BLOCK------ -----BEGIN GEEK CODE BLOCK----- Version: 3.1 GMU/S d+@ s: a- K+++++ PGP++++ K---- dpu s--:-- C++++ C-- B L X U++++ P+++ C-- P! L--- E+++ W+++ P! L--- N+++ o-- K+++++ ------END GEEK CODE BLOCK------ Plain, Loving, Useful, Mischievous, Brutal, Explosive, Responsible _______________________________________________ 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"It's making my eyes better. And it's legal. I could walk up to the President and blow smoke in his stupid monkey face, and he'd just have to sit there groovin' on it!" Homer J Simpson, Springfield, Illinois, Massachusetts nobody knows :) This email sent to site_archiver(a)lists.apple.com

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Re: Talking to MySQL from C
by Finlay Dobbie 26 Jul '05

26 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Domainkey-signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:reply-to:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=t3jeAROKaU83fh5jf6pp1mjnPa3DpsJ7KVekWgAofUAHc4b/ycFHUMTihYPNS09dUcAuORkzgwzLNIPgkrJIjUBWdJ6v4roxMDSUHsBccTebS2HTj5LZd1D5jVAx1JhQVCX5YzkQY+cyOkipGi0Gy/BCIuwTBCpjbpgp0AjBPJI= On 7/25/05, Mark Gilbert <mark(a)gallery.co.uk> wrote: > Folks. > > I am trying to write a very simple database client application in C > which will connect to a MySQL server on OSXServer. Other people have answered your question from a technical perspective, but also be aware that linking with the MySQL client library may impose licensing requirements (i.e. require you to GPL your application). -- Finlay _______________________________________________ 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: Talking to MySQL from C
by plumber 26 Jul '05

26 Jul '05

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com work with libmysqlclient gcc -o test test.c /usr/local/lib/mysql/libmysqlclient.dylib you have to setup mysql to authorize extern connexions from the clients but i think it's not the mailing list to post this ? #include <stdio.h> #include <stdlib.h> #include "/usr/local/mysql/include/mysql.h" #define table "yourtable" #define host "localhost" #define user "user" #define pass "pass" #define db "database" int main() { MYSQL mysql; MYSQL_RES *res; MYSQL_ROW row; int i=0; char query[50]; /* store the result from our query */ res = mysql_store_result(&mysql); /* fetch each row from our result and print it */ while((row = mysql_fetch_row(res))) { for(i=0;i<mysql_num_fields(res);i++) printf("%s\n",row[i]); } /* clean up */ mysql_free_result(res); mysql_close(&mysql); } also http://mysql-cocoa.sourceforge.net/ Best Regards -----BEGIN PLUMBER CODE BLOCK----- Version: 1.0 ¬ | | > Regards Plumber || GNU Darwin. ¬ \\\ plumber.gnu-darwin.org ¬ ¬ | | > OOP --\///\ (0)=(0) Darwin/Power Mac G4. ¬ | | > ( __ò ó__ ) The best for Fede ¬ \\\ federicafontana.it ¬ ------END PLUMBER CODE BLOCK------ -----BEGIN GEEK CODE BLOCK----- Version: 3.1 GMU/S d+@ s: a- K+++++ PGP++++ K---- dpu s--:-- C++++ C-- B L X U++++ P+++ C-- P! L--- E+++ W+++ P! L--- N+++ o-- K+++++ ------END GEEK CODE BLOCK------ Plain, Loving, Useful, Mischievous, Brutal, Explosive, Responsible _______________________________________________ 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… Multiple client stations would be able to add records and view records from different Macs, all sharing the one central MySQL server database. Sounds pretty simple, right ? /* make connection to the database */ if(!(mysql_connect(&mysql,host,user,pass))) { fprintf(stderr,"mysql_connect() Failed: %s\n",mysql_error (&mysql)); exit(1); } /* the database we will use */ if(mysql_select_db(&mysql,db)) { fprintf(stderr,"mysql_select_db() Failed: %s\n", mysql_error (&mysql)); exit(1); } /* Setup the query */ sprintf(query,"select * from %s", table); if(mysql_query(&mysql,query)) { fprintf(stderr,"mysql_query() Failed: %s\n", mysql_error (&mysql)); exit(1); } I"It's making my eyes better. And it's legal. I could walk up to the President and blow smoke in his stupid monkey face, and he'd just have to sit there groovin' on it!" Homer J Simpson, Springfield, Illinois, Massachusetts nobody knows :) This email sent to site_archiver(a)lists.apple.com

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