[Off Topic] Mysql system optimization to work with Freeradius

[Michell Antunes]

Sorry for the off-topic,

I have a problem with the authentication regarding the Radius with MySQL
database.
There are about 12k users who authenticate to 2 Radius servers and 1 MySQL.
Accounting is done every 5 minutes and the IPs are in a PostgreSQL base.

How much of the network is wireless during storms (I live in a tropical
country) have to disconnect multiple users and when the station is restored
have problems of "No DB Handles" which creates duplication of IP addresses
in some cases.

I have made some tests with various settings in MySQL, different file
systems and when increasing the number of clients connecting to the system
IO Wait begins to increase.
When I make an appointment for an extract over a period of time a little
bigger or my system performs the calculation of access franchise the
situation worsens.

See setups reports of Freeradius + MySQL in larger environments.
Would advise evaluate PostgreSQL? Any suggestions to optimize the system?

In the tests used a softraid (I know) and deactivated the Ext4 journaling
on which gave me a good improvement. But do not feel comfortable working
with the double filesystem + softraid, the more without journaling.

I thank in advance the opinions on this subject.

Under my system:
OS: CentOS 7
Mem: 12G
CPU: Xeon (R) CPU E5620 @ 2:40
BD: MariaDB 10.0.16
FS: EXT4 or XFS
Raid: 10 (6 SATA disks 2TB 7200 RPM 64MB WD2003FYYS Cache SATA 3.0Gb / s)

att

Michell