Re: -fno-implicit-templates, -fno-exceptions,-fno-rtti problems
Hi! You may want to try out Intel's C++ compiler for Linux if you are using an ix86 CPU. We used it here at work and it resulted in code that ran more than twice as fast, though we have never tried it with MySQL. I wonder whether Intel's C++ compiler accept those flags. Are those flags included in some standards? My problem is that I don't want the mysqld crashed randomly when I do benchmarking on it. I compiled MySQL with the Intel compiler a year ago. There was no noticeable difference in speed compared to GCC. And greetings to a fellow UofA student (though I've now graduated). thank you. I am honored. -- Regards Peng -- Peng Zhao [EMAIL PROTECTED] http://www.cs.ualberta.ca/~pengzhao TEL (Lab): (780)492-3725 Lab: CSC251 Best regards, Heikki Tuuri Innobase Oy --- Order technical MySQL/InnoDB support at https://order.mysql.com/ See http://www.innodb.com for the online manual and latest news on InnoDB - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
-fno-implicit-templates, -fno-exceptions,-fno-rtti problems
Can somebody tell me why these 3 flags must be added when I compile mysql from source code? I am trying to use another compiler instead gcc to compile mysql. But it doesnot accept these three flags. From the readme, it seems to me that these flags (especially -fno-exceptions must be used). I want to find a workaround for this issue, but first I need to know why these flags are needed. Can you explain me this? Can I eliminate these options and make mysql still runs well? thanks. Peng - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
Re: -fno-implicit-templates, -fno-exceptions,-fno-rtti problems
On Tuesday 19 February 2002 4:31 pm, Peng Zhao wrote: Can somebody tell me why these 3 flags must be added when I compile mysql from source code? I am trying to use another compiler I see no reason that these should be required. -fno-implicit-templates simply requires all templates to be explicit. -fno-exceptions tells the compiler that the code does not use exceptions (throw, catch, etc.) and results in a speed increase. -fno-rtti is for runtime type information, often used along with dynamic_cast and the like. Again, a speed increase and/or compiled code decrease if that is selected. instead gcc to compile mysql. But it doesnot accept these three flags. I'm curious... what are you using? Anyway, in summary and unless someone else speaks up, I see no reason why you'd actually need these flags. With gcc, these flags will improve performance a little but that is about all. - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
Re: -fno-implicit-templates, -fno-exceptions,-fno-rtti problems
Thanks for your reply. But You can find something from http://www.mysql.com/doc/I/B/IBM-AIX.html : If you are using gcc or egcs to compile MySQL, you must use the -fno-exceptions flag, as the exception handling in gcc/egcs is not thread safe! (This is tested with egcs 1.1.) And it also says the mysqld will crash radmonly without -fno-exceptions flag. I wonder recent gcc maybe can go on without the flags? I am using orcc to compile mysql. Can you tell me how gcc improve speed via avoiding exceptions? I mean if the source code contains throw-catch stuff, how gcc avoid that? And why throw-catch stuff is not performance friendly (just because the exception handling mechanism? but usually exceptions are very rare, there is no need to avoid exception, from this point of view)? thanks. Peng - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
Re: -fno-implicit-templates, -fno-exceptions,-fno-rtti problems
On Tuesday 19 February 2002 4:56 pm, Peng Zhao wrote: Thanks for your reply. But You can find something from http://www.mysql.com/doc/I/B/IBM-AIX.html : Thanks, I hadn't noticed that. If you are using gcc or egcs to compile MySQL, you must use the -fno-exceptions flag, as the exception handling in gcc/egcs is not thread safe! (This is tested with egcs 1.1.) And it also says the mysqld will crash radmonly without -fno-exceptions flag. I wonder recent gcc maybe can go on without the flags? To be honest, I am not sure about the later versions of gcc. It surprises me somewhat that exceptions aren't thread-safe in egcs. Still, it would be worth trying out with gcc 2.95.x or gcc 3.x. I am using orcc to compile mysql. Can you tell me how gcc improve speed via avoiding exceptions? I mean if the source code contains throw-catch stuff, how gcc avoid that? And why throw-catch stuff is not performance If the source code contains throw-catch, you are stuck. You _must_ turn on exception handling in order to use them. However, many people write code without any exceptions at all and in this case, the compiler can save some effort by not supporting them. Note, though, that most modern implementations of iostream, etc. etc. probably use exceptions. You may want to try out Intel's C++ compiler for Linux if you are using an ix86 CPU. We used it here at work and it resulted in code that ran more than twice as fast, though we have never tried it with MySQL. And greetings to a fellow UofA student (though I've now graduated). - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
Re: -fno-implicit-templates, -fno-exceptions,-fno-rtti problems
somewhat that exceptions aren't thread-safe in egcs. Still, it would be worth trying out with gcc 2.95.x or gcc 3.x. I used 2.95.3 to compile mysql, it is fine, just because it accepts those flags. I didnot try to switch those flags off and compile. I am using orcc to compile mysql. Can you tell me how gcc improve speed via avoiding exceptions? I mean if the source code contains throw-catch stuff, how gcc avoid that? And why throw-catch stuff is not performance If the source code contains throw-catch, you are stuck. You _must_ turn on exception handling in order to use them. However, many people write code without any exceptions at all and in this case, the compiler can save some effort by not supporting them. Will this improve the performance? I mean just by not supporting them, no optimization to the code? You may want to try out Intel's C++ compiler for Linux if you are using an ix86 CPU. We used it here at work and it resulted in code that ran more than twice as fast, though we have never tried it with MySQL. I wonder whether Intel's C++ compiler accept those flags. Are those flags included in some standards? My problem is that I don't want the mysqld crashed randomly when I do benchmarking on it. And greetings to a fellow UofA student (though I've now graduated). thank you. I am honored. -- Regards Peng -- Peng Zhao [EMAIL PROTECTED] http://www.cs.ualberta.ca/~pengzhao TEL (Lab): (780)492-3725 Lab: CSC251 - Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail [EMAIL PROTECTED] To unsubscribe, e-mail [EMAIL PROTECTED] Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
