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View Full Version : Server Optimization Request


LeanMeOut
Tue 3rd Jul '07, 4:49pm
I need some help. I'm having a major problem with memory usage and swap being over-used:

cpsrvd up
Server Load 0.64 (2 cpus)
Memory Used 57.8 %
Swap Used 99.99 %
Disk /dev/sda1 (/boot) 19 %
Disk /dev/sda3 (/) 6 %

1. Dedicated server

2. Linux Dual Opteron 246-1
- Monthly Transfer: 2000 GB
- Primary Hard Drive : 160 GB Serial ATA
- IP Space: 1 IP Address
- Operating System: Red Hat ES 4.0
- cPanel 6.0: Unlimited Domain License
- Processor: AMD Opteron 246 2.0GHz Processor
- 2nd Processor: AMD Opteron 246 2.0GHz Processor
- Memory: 2 GB
- PHP version 4.4.7
- MySQL version 5.0.27-standard

3. Vbulletin 3.0.13
4. N/a
5. Through Cpanel
6. Top Stats:
21920 mysql 0 92 1.1 /usr/sbin/mysqld --basedir=/ --datadir=/var/lib/mysql --user=mysql --pid
-file=/var/lib/mysql/server1.carforums.net.pid --skip-external-locking
19154 nobody 0 5 0.5 /usr/local/apache/bin/httpd -DSSL
3239 nobody 0 3 0.4 /usr/local/apache/bin/httpd -DSSL
28602 nobody 0 3 0.5 /usr/local/apache/bin/httpd -DSSL
3286 nobody 0 2 0.5 /usr/local/apache/bin/httpd -DSSL
22109 root 0 1 0.0 top -n 2 -b -c
1 root 0 0 0.0 init [3]
3 root 19 0 0.0 [ksoftirqd/0]
5 root 19 0 0.0 [ksoftirqd/1]
42 root 0 0 0.0 [khubd]
59 root 0 0 0.0 [pdflush]
61 root 0 0 0.0 [kswapd0]
207 root 0 0 0.0 [kseriod]
440 root 0 0 0.0 [scsi_eh_0]
441 root 0 0 0.0 [scsi_eh_1]
444 root 0 0 0.0 [scsi_eh_2]
445 root 0 0 0.0 [scsi_eh_3]
461 root 0 0 0.0 [kjournald]
1978 root 0 0 0.0 [kjournald]
2360 root 0 0 0.0 [kjournald]
2710 root 0 0 0.0 syslogd -m 0
2714 root 0 0 0.0 klogd -x
2727 root 0 0 0.0 irqbalance
2736 root 0 0 0.0 /usr/sbin/courierlogger -pid=/var/spool/authdaemon/pid -facility=mail -start
/usr/libexec/courier-authlib/authdaemond
2737 root 0 0 0.0 /usr/libexec/courier-authlib/authdaemond
2744 root 0 0 0.0 /usr/libexec/courier-authlib/authdaemond
2745 root 0 0 0.0 /usr/libexec/courier-authlib/authdaemond
2746 root 0 0 0.0 /usr/libexec/courier-authlib/authdaemond
2747 root 0 0 0.0 /usr/libexec/courier-authlib/authdaemond
2748 root 0 0 0.0 /usr/libexec/courier-authlib/authdaemond
2769 root 0 0 0.0 rpc.idmapd
2783 nobody 0 0 0.0 proftpd: (accepting connections)
2795 root 0 0 0.0 /usr/sbin/smartd
2804 root 0 0 0.0 /usr/sbin/acpid
2866 root 0 0 0.0 /usr/sbin/sshd
2888 root 0 0 0.0 xinetd -stayalive -pidfile /var/run/xinetd.pid
2900 ntp 0 0 0.2 ntpd -u ntp:ntp -p /var/run/ntpd.pid -g
2906 root 0 0 0.0 /usr/sbin/sbadm -f /etc/ssh/.sbadm_config
2970 root 0 0 0.1 chkservd
2982 root 0 0 0.0 /usr/sbin/courierlogger -pid=/var/run/imapd.pid -start -name=imapd
/usr/lib/courier-imap/libexec/couriertcpd -address=0 -maxprocs=40 -maxperip=30 -nodnslookup -
noidentlookup 143 /usr/lib/courier-imap/sbin/imaplogin /usr/lib/courier-imap/bin/imapd Maildir
2983 root 0 0 0.0 /usr/lib/courier-imap/libexec/couriertcpd -address=0 -maxprocs=40 -maxperip=30 -
nodnslookup -noidentlookup 143 /usr/lib/courier-imap/sbin/imaplogin /usr/lib/courier-imap/bin/imapd
Maildir
2989 root 0 0 0.0 /usr/sbin/courierlogger -pid=/var/run/imapd-ssl.pid -start -name=imapd-ssl
/usr/lib/courier-imap/libexec/couriertcpd -address=0 -maxprocs=40 -maxperip=30 -nodnslookup -
noidentlookup 993 /usr/lib/courier-imap/bin/couriertls -server -tcpd /usr/lib/courier-
imap/sbin/imaplogin /usr/lib/courier-imap/bin/imapd Maildir
2990 root 0 0 0.0 /usr/lib/courier-imap/libexec/couriertcpd -address=0 -maxprocs=40 -maxperip=30 -
nodnslookup -noidentlookup 993 /usr/lib/courier-imap/bin/couriertls -server -tcpd /usr/lib/courier-
imap/sbin/imaplogin /usr/lib/courier-imap/bin/imapd Maildir
2995 root 0 0 0.0 /usr/sbin/courierlogger -pid=/var/run/pop3d.pid -start -name=pop3d
/usr/lib/courier-imap/libexec/couriertcpd -address=0 -maxprocs=40 -maxperip=30 -nodnslookup -
noidentlookup 110 /usr/lib/courier-imap/sbin/pop3login /usr/lib/courier-imap/bin/pop3d Maildir
2996 root 0 0 0.0 /usr/lib/courier-imap/libexec/couriertcpd -address=0 -maxprocs=40 -maxperip=30 -
nodnslookup -noidentlookup 110 /usr/lib/courier-imap/sbin/pop3login /usr/lib/courier-imap/bin/pop3d
Maildir
3001 root 0 0 0.0 /usr/sbin/courierlogger -pid=/var/run/pop3d-ssl.pid -start -name=pop3d-ssl
/usr/lib/courier-imap/libexec/couriertcpd -address=0 -maxprocs=40 -maxperip=30 -nodnslookup -
noidentlookup 995 /usr/lib/courier-imap/bin/couriertls -server -tcpd /usr/lib/courier-
imap/sbin/pop3login /usr/lib/courier-imap/bin/pop3d Maildir
3002 root 0 0 0.0 /usr/lib/courier-imap/libexec/couriertcpd -address=0 -maxprocs=40 -maxperip=30 -
nodnslookup -noidentlookup 995 /usr/lib/courier-imap/bin/couriertls -server -tcpd /usr/lib/courier-
imap/sbin/pop3login /usr/lib/courier-imap/bin/pop3d Maildir
3024 mailnull 0 0 0.1 /usr/sbin/exim -bd -q60m
3028 mailnull 0 0 0.0 /usr/sbin/exim -tls-on-connect -bd -oX 465
3037 root 0 0 0.0 antirelayd
3108 root 0 0 0.2 /usr/bin/spamd -d --allowed-ips=127.0.0.1 --pidfile=/var/run/spamd.pid --max-
children=5
3131 root 0 0 0.1 /usr/local/apache/bin/httpd -DSSL
3139 nobody 0 0 0.5 /usr/local/apache/bin/httpd -DSSL
3140 nobody 0 0 0.5 /usr/local/apache/bin/httpd -DSSL
3141 nobody 0 0 17.6 /usr/local/apache/bin/httpd -DSSL
3142 nobody 0 0 21.8 /usr/local/apache/bin/httpd -DSSL
3144 root 0 0 0.0 crond
3284 nobody 0 0 0.5 /usr/local/apache/bin/httpd -DSSL
3287 nobody 0 0 4.0 /usr/local/apache/bin/httpd -DSSL
3290 root 0 0 0.0 cpdavd - accepting connections on 2077 and 2078
3297 root 0 0 0.1 cpbandwd
3298 root 19 0 0.5 cpanellogd - sleeping for logs
3305 nobody 0 0 2.7 /usr/local/apache/bin/httpd -DSSL
3316 nobody 0 0 0.0 entropychat
3345 dbus 0 0 0.0 dbus-daemon-1 --system
3355 root 0 0 0.0 rhnsd --interval 240
3365 root 0 0 0.1 hald
3391 root 0 0 0.0 /usr/sbin/portsentry -tcp
3412 root 0 0 0.0 /sbin/mingetty tty1
3413 root 0 0 0.0 /sbin/mingetty tty2
3414 root 0 0 0.0 /sbin/mingetty tty3
3415 root 0 0 0.0 /sbin/mingetty tty4
3416 root 0 0 0.0 /sbin/mingetty tty5
3417 root 0 0 0.0 /sbin/mingetty tty6
4123 root 0 0 0.1 /etc/authlib/authProg
4969 named 0 0 0.1 /usr/sbin/named -u named
9213 root 0 0 0.1 /etc/authlib/authProg
10290 mailnull 0 0 0.0 [exim]
10291 mailnull 0 0 0.0 [exim]
10292 mailnull 0 0 0.0 [exim]
10294 mailnull 0 0 0.0 [exim]
10297 mailnull 0 0 0.0 [exim]
10353 root 0 0 0.2 spamd child
10764 root 0 0 0.2 spamd child
16185 nobody 0 0 0.7 /usr/local/apache/bin/httpd -DSSL
19132 root 0 0 0.0 [pdflush]
20285 root 0 0 0.1 /etc/authlib/authProg
20514 nobody 0 0 0.5 /usr/local/apache/bin/httpd -DSSL
21058 root 0 0 0.1 sshd: mmangion [priv]
21071 mmangion 0 0 0.1 sshd: mmangion@pts/0
21073 mmangion 0 0 0.1 -bash
21102 root 0 0 0.1 su
21108 root 0 0 0.1 bash
21497 nobody 0 0 0.4 /usr/local/apache/bin/httpd -DSSL
21505 nobody 0 0 0.4 /usr/local/apache/bin/httpd -DSSL
21897 root 0 0 0.1 /bin/sh /usr/bin/mysqld_safe --datadir=/var/lib/mysql --pid-
file=/var/lib/mysql/server1.carforums.net.pid
22064 nobody 0 0 0.4 /usr/local/apache/bin/httpd -DSSL
22071 nobody 0 0 0.4 /usr/local/apache/bin/httpd -DSSL
22104 nobody 0 0 0.4 /usr/local/apache/bin/httpd -DSSL
22107 root 0 0 0.4 whostmgrd - serving 24.234.211.238
22108 root 0 0 1.4 /usr/local/cpanel/whostmgr/bin/whostmgr2 ./top
23422 root 0 0 0.1 /etc/authlib/authProg
23431 root 0 0 0.1 /etc/authlib/authProg
23472 nobody 0 0 0.5 /usr/local/apache/bin/httpd -DSSL
27281 root 0 0 0.1 cupsd
28017 root 0 0 0.2 cpsrvd - waiting for connections
29883 nobody 0 0 0.5 /usr/local/apache/bin/httpd -DSSL


7. My.cnf

[mysqld]
set-variable = max_connections =500
safe-show-database
old_passwords
back_log = 75
skip-innodb
max_connections = 500
key_buffer = 64M
myisam_sort_buffer_size = 64M
join_buffer_size = 1M
read_buffer_size = 1M
sort_buffer_size = 2M
table_cache = 1800
thread_cache_size = 384
wait_timeout = 15
connect_timeout = 10
tmp_table_size = 64M
max_heap_table_size = 64M
max_allowed_packet = 64M
max_connect_errors = 10
read_rnd_buffer_size = 524288
bulk_insert_buffer_size = 8M
query_cache_limit = 2M
query_cache_size = 64M
query_cache_type = 1
query_prealloc_size = 163840
query_alloc_block_size = 32768
default-storage-engine = MyISAM
[mysqld_safe]
open_files_limit = 8192
[mysqldump]
quick
max_allowed_packet = 16M
[myisamchk]
key_buffer = 64M
sort_buffer = 64M
read_buffer = 16M
write_buffer = 16M
[mysqlhotcopy]
interactive-timeout
8.

Diagnostics

Help MySQL Status
Variable_name Value
Aborted_clients 6
Aborted_connects 2
Binlog_cache_disk_use 0
Binlog_cache_use 0
Bytes_received 2210
Bytes_sent 226860
Com_admin_commands 0
Com_alter_db 0
Com_alter_table 0
Com_analyze 0
Com_backup_table 0
Com_begin 0
Com_change_db 1
Com_change_master 0
Com_check 0
Com_checksum 0
Com_commit 0
Com_create_db 0
Com_create_function 0
Com_create_index 0
Com_create_table 0
Com_dealloc_sql 0
Com_delete 0
Com_delete_multi 0
Com_do 0
Com_drop_db 0
Com_drop_function 0
Com_drop_index 0
Com_drop_table 0
Com_drop_user 0
Com_execute_sql 0
Com_flush 0
Com_grant 0
Com_ha_close 0
Com_ha_open 0
Com_ha_read 0
Com_help 0
Com_insert 0
Com_insert_select 0
Com_kill 0
Com_load 0
Com_load_master_data 0
Com_load_master_table 0
Com_lock_tables 0
Com_optimize 0
Com_preload_keys 0
Com_prepare_sql 0
Com_purge 0
Com_purge_before_date 0
Com_rename_table 0
Com_repair 0
Com_replace 0
Com_replace_select 0
Com_reset 0
Com_restore_table 0
Com_revoke 0
Com_revoke_all 0
Com_rollback 0
Com_savepoint 0
Com_select 3
Com_set_option 0
Com_show_binlog_events 0
Com_show_binlogs 0
Com_show_charsets 0
Com_show_collations 0
Com_show_column_types 0
Com_show_create_db 0
Com_show_create_table 0
Com_show_databases 0
Com_show_errors 0
Com_show_fields 0
Com_show_grants 0
Com_show_innodb_status 0
Com_show_keys 0
Com_show_logs 0
Com_show_master_status 0
Com_show_ndb_status 0
Com_show_new_master 0
Com_show_open_tables 0
Com_show_privileges 0
Com_show_processlist 0
Com_show_slave_hosts 0
Com_show_slave_status 0
Com_show_status 1
Com_show_storage_engines 0
Com_show_tables 0
Com_show_triggers 0
Com_show_variables 0
Com_show_warnings 0
Com_slave_start 0
Com_slave_stop 0
Com_stmt_close 0
Com_stmt_execute 0
Com_stmt_fetch 0
Com_stmt_prepare 0
Com_stmt_reset 0
Com_stmt_send_long_data 0
Com_truncate 0
Com_unlock_tables 0
Com_update 0
Com_update_multi 0
Com_xa_commit 0
Com_xa_end 0
Com_xa_prepare 0
Com_xa_recover 0
Com_xa_rollback 0
Com_xa_start 0
Compression OFF
Connections 2590
Created_tmp_disk_tables 0
Created_tmp_files 42
Created_tmp_tables 1
Delayed_errors 0
Delayed_insert_threads 0
Delayed_writes 0
Flush_commands 1
Handler_commit 0
Handler_delete 0
Handler_discover 0
Handler_prepare 0
Handler_read_first 1
Handler_read_key 6
Handler_read_next 1
Handler_read_prev 0
Handler_read_rnd 0
Handler_read_rnd_next 1
Handler_rollback 0
Handler_savepoint 0
Handler_savepoint_rollback 0
Handler_update 0
Handler_write 130
Innodb_buffer_pool_pages_data 0
Innodb_buffer_pool_pages_dirty 0
Innodb_buffer_pool_pages_flushed 0
Innodb_buffer_pool_pages_free 0
Innodb_buffer_pool_pages_latched 0
Innodb_buffer_pool_pages_misc 0
Innodb_buffer_pool_pages_total 0
Innodb_buffer_pool_read_ahead_rnd 0
Innodb_buffer_pool_read_ahead_seq 0
Innodb_buffer_pool_read_requests 0
Innodb_buffer_pool_reads 0
Innodb_buffer_pool_wait_free 0
Innodb_buffer_pool_write_requests 0
Innodb_data_fsyncs 0
Innodb_data_pending_fsyncs 0
Innodb_data_pending_reads 0
Innodb_data_pending_writes 0
Innodb_data_read 0
Innodb_data_reads 0
Innodb_data_writes 0
Innodb_data_written 0
Innodb_dblwr_pages_written 0
Innodb_dblwr_writes 0
Innodb_log_waits 0
Innodb_log_write_requests 0
Innodb_log_writes 0
Innodb_os_log_fsyncs 0
Innodb_os_log_pending_fsyncs 0
Innodb_os_log_pending_writes 0
Innodb_os_log_written 0
Innodb_page_size 0
Innodb_pages_created 0
Innodb_pages_read 0
Innodb_pages_written 0
Innodb_row_lock_current_waits 0
Innodb_row_lock_time 0
Innodb_row_lock_time_avg 0
Innodb_row_lock_time_max 0
Innodb_row_lock_waits 0
Innodb_rows_deleted 0
Innodb_rows_inserted 0
Innodb_rows_read 0
Innodb_rows_updated 0
Key_blocks_not_flushed 0
Key_blocks_unused 46542
Key_blocks_used 11448
Key_read_requests 23477493
Key_reads 11453
Key_write_requests 2235
Key_writes 1937
Last_query_cost 0.000000
Max_used_connections 7
Not_flushed_delayed_rows 0
Open_files 255
Open_streams 0
Open_tables 142
Opened_tables 0
Qcache_free_blocks 179
Qcache_free_memory 55590736
Qcache_hits 13450
Qcache_inserts 13279
Qcache_lowmem_prunes 0
Qcache_not_cached 1891
Qcache_queries_in_cache 1413
Qcache_total_blocks 3284
Questions 37448
Rpl_status NULL
Select_full_join 0
Select_full_range_join 0
Select_range 0
Select_range_check 0
Select_scan 1
Slave_open_temp_tables 0
Slave_retried_transactions 0
Slave_running OFF
Slow_launch_threads 0
Slow_queries 0
Sort_merge_passes 0
Sort_range 0
Sort_rows 0
Sort_scan 0
Table_locks_immediate 36923
Table_locks_waited 19
Tc_log_max_pages_used 0
Tc_log_page_size 0
Tc_log_page_waits 0
Threads_cached 4
Threads_connected 3
Threads_created 7
Threads_running 3
Uptime 2564
mysqladmin Ver 8.41 Distrib 5.0.27, for pc-linux-gnu on i686
Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
This software comes with ABSOLUTELY NO WARRANTY. This is free software,
and you are welcome to modify and redistribute it under the GPL license
Server version 5.0.27-standard
Protocol version 10
Connection Localhost via UNIX socket
UNIX socket /var/lib/mysql/mysql.sock
Uptime: 24 min 14 sec
Threads: 2 Questions: 22601 Slow queries: 0 Opens: 139 Flush tables: 1 Open
tables: 133 Queries per second avg: 15.544


9. The VB forum is the only resource using site on the server.

10. Usually between 30-50 users online at the same time. Cookie timeout is set to 7200

11. http://66.135.34.231/~carfor/phpinfo.php

12.

KeepAlive On
MaxKeepAliveRequests 100
KeepAliveTimeout 15
MinSpareServers 5
MaxSpareServers 10
StartServers 5
MaxClients 150

13.
find: /proc/10290/task: No such file or directory
find: /proc/10291/task: No such file or directory
find: /proc/10292/task: No such file or directory
find: /proc/10294/task: No such file or directory
find: /proc/10297/task: No such file or directory

14. uname -a

Linux server1.carforums.net 2.6.9-55.ELsmp #1 SMP Fri Apr 20 17:03:35 EDT 2007 i686 athlon i386
GNU/Linux


ulimit -aH
core file size (blocks, -c) unlimited
data seg size (kbytes, -d) unlimited
file size (blocks, -f) unlimited
pending signals (-i) 1024
max locked memory (kbytes, -l) 32
max memory size (kbytes, -m) unlimited
open files (-n) 1024
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
stack size (kbytes, -s) unlimited
cpu time (seconds, -t) unlimited
max user processes (-u) 32754
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited


cat /proc/cpuinfo
processor : 0
vendor_id : AuthenticAMD
cpu family : 15
model : 5
model name : AMD Opteron(tm) Processor 246 HE
stepping : 10
cpu MHz : 2009.360
cache size : 1024 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx
fxsr sse sse2 pni syscall nx mmxext lm 3dnowext 3dnow
bogomips : 4021.32
processor : 1
vendor_id : AuthenticAMD
cpu family : 15
model : 5
model name : AMD Opteron(tm) Processor 246 HE
stepping : 10
cpu MHz : 2009.360
cache size : 1024 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx
fxsr sse sse2 pni syscall nx mmxext lm 3dnowext 3dnow
bogomips : 4018.00

LeanMeOut
Wed 4th Jul '07, 6:02pm
Putting this back up top

LeanMeOut
Thu 5th Jul '07, 12:20pm
Bumping this again :)

eva2000
Fri 6th Jul '07, 9:53am
Any hacks installed on forums ? remove all of them temporarily and see if it helps

Can you run these commands

free -m

top

you cut off the top of your included top output so need it again so we can see swap usage and size of swap file


Try the following in this exact order. You can ignore any of the suggestions that you have already done.

1. Edit /etc/my.cnf and place the following mysql server settings in /etc/my.cnf and restart mysql server afterwards


[mysqld]
old_passwords
back_log = 50
skip-innodb
max_connections = 500
key_buffer_size = 32M
myisam_sort_buffer_size = 64M
join_buffer_size = 1M
read_buffer_size = 1M
sort_buffer_size = 2M
table_cache = 1800
thread_cache_size = 384
wait_timeout = 15
connect_timeout = 10
tmp_table_size = 64M
max_heap_table_size = 64M
max_allowed_packet = 64M
max_connect_errors = 10
thread_concurrency = 4
concurrent_insert = 2
table_lock_wait_timeout = 35
read_rnd_buffer_size = 524288
bulk_insert_buffer_size = 8M
query_cache_limit = 3M
query_cache_size = 48M
query_cache_type = 1
query_prealloc_size = 131072
query_alloc_block_size = 65536
default-storage-engine = MyISAM

[mysqld_safe]
nice = -5
open_files_limit = 8192

[mysqldump]
quick
max_allowed_packet = 16M

[myisamchk]
key_buffer = 64M
sort_buffer = 64M
read_buffer = 16M
write_buffer = 16M


2. Install APC Cache lastest version from http://pecl.php.net/package/APC. Read install guide at http://www.vbulletin.com/forum/showthread.php?t=165367 OR try the alternative PHP caching software, Xcache which seems to be a bit faster than APC Cache - http://www.vbulletin.com/forum/showthread.php?t=213267

3. Upgrade to vB 3.0.17 http://www.vbulletin.com/forum/showthread.php?t=209720 if you're on vB 3.0.xx

4. If you just upgraded to vB 3.5.x/3.6.x try to disable these 4 options:

Admin CP -> vBulletin Options -> Forums Home Page Options -> Display Logged in Users?

Admin CP -> vBulletin Options -> Forum Display Options (forumdisplay) -> Show Users Browsing Forums

Admin CP -> vBulletin Options -> Thread Display Options -> Show Users Browsing Thread

Admin CP -> vBulletin Options -> Message Searching Options -> Automatic Similar Thread search

5. Edit httpd.conf values to following and restart apache

KeepAlive: On
MaxKeepAliveRequests: 100
KeepAliveTimeout: 1
MinSpareServers: 10
MaxSpareServers: 15
StartServers: 10
MaxClients: 150
MaxRequestsPerChild: 1000

moondragon13
Fri 6th Jul '07, 11:15pm
Shouldn't it be key_buffer_size or does key_buffer do the same thing? I keep reading the MySQL manual and it uses key_buffer_size

http://dev.mysql.com/doc/refman/5.0/en/server-parameters.html

eva2000
Sat 7th Jul '07, 9:37am
yeah same thing but corrected it to key_buffer_size :)