what causes core dumps, and how can I fix the problem?

[SoftDux]

Hi,

Every now and then I get a client saying their account is over-quota but they don't have much on their websites. Upon inspection, I often see core dump files (/home/webhost/public_html/core.11050)

What causes core dump files on shared hosting account, and how can I fix it? How can I even debug it?

 

[whplus]

You can use the strings command to process the core dump file.

strings /home/webhost/public_html/core.11050|head

susan,

 

[SoftDux]

Thank you Susan,

I get the following:

strings /home/webhost/public_html/core.11050|head
CORE
CORE
/usr/bin/php /home/webhost/public_html/showthread.php
CORE
CORE
 D
[email protected]
`&f&`
!!T^
"!L^

Which doesn't mean much to me. What causes the core dumps though?

 

[whplus]

It seems php cause core dumps. Use gdb to debug and see the result

gdb /usr/bin/php /home/webhost/public_html/core.11050

susan,

 

[SoftDux]

It seems php cause core dumps. Use gdb to debug and see the result

Thanx, now I got something:

warning: exec file is newer than core file.
Core was generated by `/usr/bin/php /home/webhost/public_html/showthread.php'.
Program terminated with signal 24, CPU time limit exceeded.
#0 0x000000000047feb1 in compile_regex (options=<value optimized out>, oldims=0, codeptr=0x20000000, ptrptr=0x0, errorcodeptr=0x1, lookbehind=32767,
reset_bracount=708, skipbytes=-1306236605, firstbyteptr=0xe8, reqbyteptr=0x166, bcptr=0xf230641, cd=0x3, lengthptr=0x0)
at /home/cpeasyapache/src/php-5.2.6/ext/pcre/pcrelib/pcre_compile.c:4070
4070 case OP_PLUS: *tempcode = OP_POSPLUS; break;

From this I can see that it's caused by "Program terminated with signal 24, CPU time limit exceeded."

So, what determines how much CPS time a script can use, and when to terminated it?