Many unauthenticated user, writing to net after using show processlist command

Many unauthenticated user, writing to net after using show processlist command

Đặng Quang Hùng
Vastuste arv 6
Hi all,

I've got many unauthenticated user, writing to net, reading from net, ... when use "show processlist" command in myslql. It makes database server be full of processes and moodle's performance is so slow.

I've tried scp command to test data transfer speed between webserver and database server. The result that:
- It's very slow if mysql still running in db server (about 500KB/s).
- It's very fast if I stop mysql in db server (about 40MB/s)

What happen? Who can help me to solve that problem.

Thanks.
Keskmine hinnang: -
Vastuses Đặng Quang Hùng

Re: Many unauthenticated user, writing to net after using show processlist command

Jai Gupta
Few things you could check.
  1. LAN speed between servers (should be 1Gbps).
  2. Is mysql connection slow? (this could be because of DNS)
Vastuses Jai Gupta

Re: Many unauthenticated user, writing to net after using show processlist command

Đặng Quang Hùng
Yes, Lan speed is 1GBps and I'm using ip for connection. Any ideas?
Vastuses Đặng Quang Hùng

Re: Many unauthenticated user, writing to net after using show processlist command

Jai Gupta
This is the first time for me when network connection (with 1GBps LAN) has become a bottleneck for database.

Have you tried installing Memcached on webserver? This may reduce network bandwidth.
Vastuses Jai Gupta

Re: Many unauthenticated user, writing to net after using show processlist command

Đặng Quang Hùng
Thanks for your suggestion. Actually, I've not tried it yet. Plz guide me more in detail.

Thanks a lot.
Vastuses Đặng Quang Hùng

Re: Many unauthenticated user, writing to net after using show processlist command

Jai Gupta
http://en.wikipedia.org/wiki/Memcached

Memcached is basically a caching system for database. If you install it on webserver then it may cache a reasonable amount of data in webserver, reducing the calls to db server hence reducing bandwidth.

You can download it from http://www.danga.com/memcached/download.bml