Tune Mysql

I am running on a VPS which so far seems to be great, but at times I see some pauses. I have been working to tune mysql and so far have seen some good improvements. I am confused some sample my.cnf's which show dedicated myisamchk buffers. Do the normal buffers not count?

My current VPS has 768MB of dedicated ram, and is on a new 8 way server utilizing virtuozzo. On Unix bench I receive between a 190 - 240.

I am running 3 sites, and only one of which has notable traffic. it is a phpBB2 site with 30-50 concurrent users. The database is roughly 300MB and 4million records.

As stated at times there seems to be pauses and I am unsure if is simple related to the nature of the VPS or if I have some tuning left to do. Below are the stats I have gathered and I can provide more information if needed.

I will say that query cache does not seem to benefit phpBB2 as I was only getting 1-2:1 hit ratio.

my.cnf:

Quote:

[mysqld]
max_connections = 120
table_cache = 500
key_buffer_size = 80M
join_buffer_size = 1M
read_rnd_buffer_size = 768K
thread_cache_size = 50
thread_concurrency = 2
safe-show-database

tuning-primer.sh:

Quote:

MySQL Version 4.1.22-standard i686

Uptime = 0 days 20 hrs 56 min 1 sec
Avg. qps = 7
Total Questions = 535268
Threads Connected = 5

Warning: Server has not been running for at least 48hrs.
It may not be safe to use these recommendations

To find out more information on how each of these
runtime variables effects performance visit:
[url]

SLOW QUERIES
Current long_query_time = 10 sec.
You have 996 out of 535280 that take longer than 10 sec. to complete
The slow query log is NOT enabled.
Your long_query_time may be too high, I typically set this under 5 sec.

WORKER THREADS
Current thread_cache_size = 50
Current threads_cached = 46
Current threads_per_sec = 0
Historic threads_per_sec = 0
Your thread_cache_size is fine

MAX CONNECTIONS
Current max_connections = 120
Current threads_connected = 4
Historic max_used_connections = 50
The number of used connections is 41% of the configured maximum.
Your max_connections variable seems to be fine.

MEMORY USAGE
Max Memory Ever Allocated : 292 M
Configured Max Per-thread Buffers : 486 M
Configured Max Global Buffers : 90 M
Configured Max Memory Limit : 576 M
Total System Memory : 768.00 M
Max memory limit seem to be within acceptable norms

KEY BUFFER
Current MyISAM index space = 117 M
Current key_buffer_size = 80 M
Key cache miss rate is 1 : 30980
Key buffer fill ratio = 70.00 %
Your key_buffer_size seems to be too high.
Perhaps you can use these resources elsewhere

QUERY CACHE
Query cache is supported but not enabled
Perhaps you should set the query_cache_size

SORT OPERATIONS
Current sort_buffer_size = 2 M
Current record/read_rnd_buffer_size = 764 K
Sort buffer seems to be fine

JOINS
Current join_buffer_size = 1.00 M
You have had 2779 queries where a join could not use an index properly
You should enable "log-queries-not-using-indexes"
Then look for non indexed joins in the slow query log.
If you are unable to optimize your queries you may want to increase your
join_buffer_size to accommodate larger joins in one pass.

Note! This script will still suggest raising the join_buffer_size when
ANY joins not using indexes are found.

OPEN FILES LIMIT
Current open_files_limit = 1130 files
The open_files_limit should typically be set to at least 2x-3x
that of table_cache if you have heavy MyISAM usage.
Your open_files_limit value seems to be fine

TABLE CACHE
Current table_cache value = 500 tables
You have a total of 204 tables
You have 438 open tables.
The table_cache value seems to be fine

TEMP TABLES
Current max_heap_table_size = 16 M
Current tmp_table_size = 32 M
Of 45794 temp tables, 4% were created on disk
Effective in-memory tmp_table_size is limited to max_heap_table_size.
Created disk tmp tables ratio seems fine

TABLE SCANS
Current read_buffer_size = 128 K
Current table scan ratio = 929 : 1
read_buffer_size seems to be fine

TABLE LOCKING
Current Lock Wait ratio = 1 : 47
You may benefit from selective use of InnoDB.
If you have long running SELECT's against MyISAM tables and perform
frequent updates consider setting 'low_priority_updates=1'

mysqlreport:

Code:
MySQL 4.1.22-standard uptime 0 20:57:20 Thu Dec 13 18:07:02 2007

__ Key _________________________________________________________________
Buffer used 50.00M of 80.00M %Used: 62.50
Current 59.10M %Usage: 73.87
Write hit 37.16%
Read hit 100.00%

__ Questions ___________________________________________________________
Total 536.23k 7.1/s
DMS 466.89k 6.2/s %Total: 87.07
Com_ 37.48k 0.5/s 6.99
COM_QUIT 31.83k 0.4/s 5.94
+Unknown 28 0.0/s 0.01
Slow 997 0.0/s 0.19 %DMS: 0.21
DMS 466.89k 6.2/s 87.07
SELECT 398.63k 5.3/s 74.34 85.38
UPDATE 43.35k 0.6/s 8.08 9.28
DELETE 17.53k 0.2/s 3.27 3.75
INSERT 7.38k 0.1/s 1.38 1.58
REPLACE 11 0.0/s 0.00 0.00
Com_ 37.48k 0.5/s 6.99
change_db 30.51k 0.4/s 5.69
show_status 2.11k 0.0/s 0.39
show_proces 2.08k 0.0/s 0.39

__ SELECT and Sort _____________________________________________________
Scan 192.22k 2.5/s %SELECT: 48.22
Range 12.28k 0.2/s 3.08
Full join 2.78k 0.0/s 0.70
Range check 0 0/s 0.00
Full rng join 0 0/s 0.00
Sort scan 79.22k 1.1/s
Sort range 29.26k 0.4/s
Sort mrg pass 1.13k 0.0/s

__ Table Locks _________________________________________________________
Waited 14.12k 0.2/s %Total: 2.08
Immediate 666.09k 8.8/s

__ Tables ______________________________________________________________
Open 438 of 500 %Cache: 87.60
Opened 452 0.0/s

__ Connections _________________________________________________________
Max used 50 of 120 %Max: 41.67
Total 31.83k 0.4/s

__ Created Temp ________________________________________________________
Disk table 1.95k 0.0/s
Table 45.86k 0.6/s
File 2.27k 0.0/s

__ Threads _____________________________________________________________
Running 1 of 4
Cached 46 of 50 %Hit: 99.84
Created 50 0.0/s
Slow 0 0/s

__ Aborted _____________________________________________________________
Clients 4 0.0/s
Connects 0 0/s

__ Bytes _______________________________________________________________
Sent 1.11G 14.7k/s
Received 182.99M 2.4k/s