Why mysqld keep crashing (cannot start MAMP)? - mysql

Question

I can't start MAMP server.
Apache is just works, but MySQL keep crashing, the error log is just growing, and never stop.
Can I recover this issue somehow?
Can I reinstall MySQL components without losing my data?
16:29:21 UTC - mysqld got signal 6 ;
This could be because you hit a bug. It is also possible that this binary
or one of the libraries it was linked against is corrupt, improperly built,
or misconfigured. This error can also be caused by malfunctioning hardware.
We will try our best to scrape up some info that will hopefully help
diagnose the problem, but since we have already crashed,
something is definitely wrong and this may fail.
key_buffer_size=8388608
read_buffer_size=131072
max_used_connections=0
max_threads=151
thread_count=0
connection_count=0
It is possible that mysqld could use up to
key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 338490 K bytes of memory
Hope that's ok; if not, decrease some variables in the equation.
Thread pointer: 0x0
Attempting backtrace. You can use the following information to find out
where mysqld died. If you see no messages after this, something went
terribly wrong...
stack_bottom = 0 thread_stack 0x40000
0 mysqld 0x000000010027ee9c my_print_stacktrace + 44
1 mysqld 0x0000000100021434 handle_fatal_signal + 692
2 libsystem_c.dylib 0x00007fff9148090a _sigtramp + 26
3 mysqld 0x00000001002f5d77 mtr_memo_push + 23
4 libsystem_c.dylib 0x00007fff914d7f61 abort + 143
5 mysqld 0x00000001002c049a dict_foreign_add_to_cache + 1018
6 mysqld 0x00000001002c602c dict_load_foreigns + 1436
7 mysqld 0x00000001002c81b8 dict_load_table + 1720
8 mysqld 0x00000001002c859b dict_load_table_on_id + 459
9 mysqld 0x000000010032bd1d row_purge_step + 381
10 mysqld 0x0000000100308856 que_thr_step + 534
11 mysqld 0x0000000100308a6d que_run_threads + 125
12 mysqld 0x000000010034223c trx_purge + 636
13 mysqld 0x000000010033816c srv_master_do_purge + 44
14 mysqld 0x0000000100338ed1 srv_master_thread + 2513
15 libsystem_c.dylib 0x00007fff91492772 _pthread_start + 327
16 libsystem_c.dylib 0x00007fff9147f1a1 thread_start + 13
The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains
information that should help you find out what is causing the crash.
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Answer 1

You can install MySQL without losing data but you have to backup the contents of (MySQL-home-folder)/data folder (of course)
But the fundamental problem seems to be using the ready-made MAMP set. Try installing each (apache, mysql, php) separately into their native home folders. As an example from my perfectly running AMP setup:
Apache --> /usr/local/apache2/bin/httpd
MySQL --> /usr/local/mysql-5.1.40-osx10.5-powerpc/bin/mysqld
PHP --> /usr/local/apache2/modules/libphp5.so
For further details on this kind of setup, see diymacserver.com.
If you want nothing but ready-made MAMP package, then try different versions of MAMP.