Blank Index.html - Loads Fine. Remove Index.html, Load Goes Up

[Bobsuch]

Hi,



I seem to be having a problem.

Seems the forum is crashing the server.


So I put in a blank index.html file and renamed my forum's index.php to index.php_
The load then seems to settle.

As soon as I rename the index.html file, and rename the forum's index.php to index.php the load goes up by the 2-4's per second.


What could be wrong?
Could it be a ddos attack? If it was, howcome the load is fine with the blank index.html file?

[bfarber]

Firstly, there is next to no processing by your server to load an html file, so if it were a ddos attack, you could see the same results. You'd have to check your access logs and or active network connections (while the issue is occurring) to know for sure.

When this sort of thing happens, check top output at command line - is it mysql or apache using up the processing? If it's mysql, run something like

watch mysqladmin processlist

Or login to mysql and run the query

show processlist

to see what queries are causing the problems. If it's apache, then you probably need to optimize your apache configuration somehow.

If it's anything else, it's probable that you just need to shut down that process and let it resume later. i.e. stats, database backups, and email programs can cause load issues if they have a lot of work to do during peak times.

[Bobsuch]

This is top when I let the forum run:

Tasks: 341 total, 31 running, 310 sleeping, 0 stopped, 0 zombie Cpu(s): 92.9% us, 6.8% sy, 0.0% ni, 0.2% id, 0.0% wa, 0.2% hi, 0.0% si Mem: 4146296k total, 3655524k used, 490772k free, 34004k buffers Swap: 2031608k total, 0k used, 2031608k free, 464676k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 5570 mysql 16 0 284m 141m 4016 S 15 3.5 0:53.07 /usr/libexec/mysqld --defaults-file=/etc/my.cnf --basedir=/usr --datadir=/var/lib 9175 apache 17 0 41148 23m 3612 R 7 0.6 0:00.63 /usr/sbin/httpd 9723 apache 17 0 34512 16m 3572 R 6 0.4 0:00.21 /usr/sbin/httpd 8468 apache 15 0 41208 23m 3836 S 5 0.6 0:02.40 /usr/sbin/httpd 9405 apache 17 0 41144 22m 3564 S 5 0.6 0:00.34 /usr/sbin/httpd 6101 apache 16 0 41268 23m 3848 S 4 0.6 0:03.05 /usr/sbin/httpd 9171 apache 16 0 41172 23m 3808 S 4 0.6 0:00.65 /usr/sbin/httpd 9367 apache 15 0 41144 22m 3564 S 4 0.6 0:00.33 /usr/sbin/httpd 9427 apache 17 0 41168 22m 3564 S 4 0.6 0:00.32 /usr/sbin/httpd 9535 apache 17 0 41144 22m 3564 S 4 0.6 0:00.33 /usr/sbin/httpd 9403 apache 17 0 35828 17m 3460 R 4 0.4 0:00.16 /usr/sbin/httpd 9413 apache 15 0 41140 22m 3536 S 4 0.6 0:00.34 /usr/sbin/httpd 9421 apache 16 0 41120 23m 3600 S 4 0.6 0:00.66 /usr/sbin/httpd 9507 apache 15 0 41172 22m 3564 S 4 0.6 0:00.34 /usr/sbin/httpd 9615 apache 16 0 37308 19m 3512 S 4 0.5 0:00.19 /usr/sbin/httpd 9693 apache 17 0 41124 22m 3520 R 4 0.6 0:00.29 /usr/sbin/httpd 9722 apache 16 0 33924 16m 3776 S 4 0.4 0:00.18 /usr/sbin/httpd 9212 apache 17 0 41148 23m 3612 S 4 0.6 0:00.73 /usr/sbin/httpd 9447 apache 17 0 41124 22m 3484 R 4 0.6 0:00.28 /usr/sbin/httpd 9539 apache 17 0 35856 17m 3464 R 4 0.4 0:00.16 /usr/sbin/httpd 9548 apache 15 0 41152 22m 3564 S 4 0.6 0:00.33 /usr/sbin/httpd 9558 apache 17 0 35828 17m 3460 R 4 0.4 0:00.16 /usr/sbin/httpd 9710 apache 16 0 33172 15m 3608 R 4 0.4 0:00.14 /usr/sbin/httpd 9718 apache 17 0 35828 17m 3460 R 4 0.4 0:00.16 /usr/sbin/httpd 9719 apache 17 0 35828 17m 3432 R 4 0.4 0:00.16 /usr/sbin/httpd 9508 apache 17 0 41156 22m 3520 R 3 0.6 0:00.28 /usr/sbin/httpd 9510 apache 16 0 41172 22m 3564 S 3 0.6 0:00.35 /usr/sbin/httpd 9639 apache 17 0 35828 17m 3460 R 3 0.4 0:00.15 /usr/sbin/httpd 9724 apache 17 0 35856 17m 3464 R 3 0.4 0:00.16 /usr/sbin/httpd 9407 apache 17 0 41124 22m 3484 R 3 0.6 0:00.27 /usr/sbin/httpd 9538 apache 17 0 41124 22m 3480 R 3 0.6 0:00.26 /usr/sbin/httpd 9660 apache 16 0 36612 18m 3428 R 3 0.5 0:00.15 /usr/sbin/httpd 6025 apache 16 0 41168 23m 3836 S 3 0.6 0:04.56 /usr/sbin/httpd

top - 11:33:34 up 15 min,  2 users,  load average: 12.12, 6.08, 5.39

So it has to be apache causing the problem?

[bfarber]

It looks like mysql in that output..