Hi, I have a similar load problem when I start MySQL-4.0 and there is high number of apache process requesting MySQL connection. I had to shutdown and restart apache otherwise the load often goes up to 200 and more (!!). (there are more than 250 visitors always connected to the server, so it generates high stress for the server). This behaviour seems to occur since we upgrade the server from 2.2.x kernel to 2.4.x kernel (actually a 2.4.12-ac6 kernel). I'm wondering if this issue couldn't be linked to the new VM in 2.4.x kernel...
If someone have any idea about how to solve this problem... Thanks in advance :) Jocelyn Fournier Presence-PC ----- Original Message ----- From: "Arndt Jenssen" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, December 12, 2001 8:27 PM Subject: High load problem with 3.23.45 > Maybe some coding/mysql master out there knows an answer to this tricky > problem... > > We've recently migrated all our mysql servers from 3.23.42 to 3.23.45 without > any problems except for one server. > That linux server shows after startup of mysql after 1 or 2 minutes an > exceptionally high load and the load will rise until the server ends up in > nirvana (I've seen a load of 80 and more) > > Some infos on the server: > Distribution: Suse 7.2 > kernel: 2.4.4 > glibc: 2.2.2 > gcc: 2.9.53 > > We've profiled mysqld with following results (grpof): > > *********************************** > Flat profile: > > Each sample counts as 0.01 seconds. > % cumulative self self total > time seconds seconds calls us/call us/call name > 48.10 4.69 4.69 3682 1273.76 1273.76 _nl_get_alt_digit > 23.90 7.02 2.33 getpid > 20.92 9.06 2.04 regex_compile > 4.10 9.46 0.40 708096 0.56 0.56 __array_type_info > type_info function > 1.44 9.60 0.14 lock_update_insert > 0.31 9.63 0.03 12 2500.00 2500.09 chk_del > 0.21 9.65 0.02 288 69.44 69.44 find_best(JOIN *, > unsigned long, unsigned int, double, double) > 0.21 9.67 0.02 __mktime_internal > 0.10 9.68 0.01 285302 0.04 0.04 sort_get_next_record > 0.10 9.69 0.01 21066 0.47 0.47 _IO_vfscanf > 0.10 9.70 0.01 4106 2.44 9.73 > mysql_execute_command(void) > ******************* > As you can see most of the time is spend in the functions _nl_get_alt_digit, > getpid and regex_compile. > > The profile log of another server running mysql 3.23.45 looks completely > different. Most of the time on this server is spend in the select method what > seems to be just perfect. > > Here is the profile log of the functioning server: > *********************************** > Flat profile: > > Each sample counts as 0.01 seconds. > % cumulative self self total > time seconds seconds calls us/call us/call name > 13.92 0.11 0.11 select > 11.39 0.20 0.09 1 90000.00 93333.33 buf_pool_create > 7.59 0.26 0.06 memset > 6.33 0.31 0.05 __libc_accept > 6.33 0.36 0.05 __mcount_internal > 6.33 0.41 0.05 chunk_alloc > 6.33 0.46 0.05 vfprintf > 5.06 0.50 0.04 3363 11.89 11.89 init_io_cache > 5.06 0.54 0.04 > pthread_handle_sigrestart > 2.53 0.56 0.02 2721 7.35 7.35 create_new_thread(THD *) > 2.53 0.58 0.02 12 1666.67 1666.67 hash_create > 2.53 0.60 0.02 1 20000.00 21666.67 > recv_apply_hashed_log_recs > 2.53 0.62 0.02 __pthread_alt_unlock > ****************************************************** > > We've compiled mysql on both servers with following configure options: > > CFLAGS="-O3 -p -mpentiumpro" CXX=gcc CXXFLAGS="-O3 -p -mpentiumpro > -felide-constructors -fno-exceptions -fno-rtti" ./configure > --prefix=/usr/local/mysql --enable-assembler --with-debug > --with-mysqld-ldflags="-all-static -p" --localstatedir=/usr/local/mysql/da ta > -with-innodb > > And both servers are running the same system and (hopefully) the same > configuration. > > Any ideas.... > > Thanks in advance for your help. > > --------------------------------------------------------------------- > 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 > > --------------------------------------------------------------------- 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
