Modifying my.cnf to make my board and server work better

[SecondSight]

Hello !

I've made modifications to my.cnf and then restarted mysql.

At the same time I was looking at the server status and I noticed that :
- before I restarted the server, the "Memory used" value was 20 % (with 80 users online), the "Server load" value was about 0.30/0.70, and the "Swap used" value was 5 %.
- after I restarted the server, the "Memory used" value was between 8 and 9 % and the "Swap used" value was 0.28 %.

Now (45 minutes after I restarted the server), I have 280 users online and the values are about the same (the "Memory used" value is now between 9 and 10 %).

As for the "memory used" value, what can explain the difference ? It was 20 % with only 80 users online, before I restarted the server. Does it mean there is something wrong in my.cnf ?

Anyway, I have white pages at moments (as if something is timing out) and I wonder how I can resolve this problem.

My my.cnf is :

[mysqld]

max_user_connections=500

max_connections=850

max_allowed_packet=1M

key_buffer_size=1024M

sort_buffer_size=8M

join_buffer_size=2M

read_buffer_size=6M

read_rnd_buffer_size=6M

max_heap_table_size=64M

table_cache=2000

thread_cache_size=512

tmp_table_size=64M

myisam_sort_buffer_size=512M

query_cache_size=512M

query_cache_limit=6M

interactive_timeout=60

wait_timeout=100

My server is :
Dual Processor Quad Core Xeon 5345 - 2.33GHz,
Second Processor Quad Core Xeon 5345 - 2.33GHz
6 Giga de Ram and 2 RAID 1 SCSI disks

Thank you for your help ! :)

[bfarber]

If you have whitepages, that would explain why memory used is so low - it's not using any memory because it can't serve anything. Find out what the white pages are caused by (error logs perhaps would help).

[SecondSight]

Hello ! :)

Now the "Memory used" value is about 13 or 14 % with 550 users online.

But I didn't explain myself very well about the white pages problem : in fact, I've been having white pages since several days.
The "wait_timeout" value was 60 and today I changed it to 100...

[SecondSight]

In fact, there must be a problem somewhere :

Server Load 6.57 (8 cpus)
Memory Used 45.5 %
Swap Used 21.87 %

I will open a support ticket.