Toror

speed-core:
Например: Оверсан.

sladkydze:
ПолуОФФ. Учитывая текущее положение дел, рекомендовал бы не покупать сервер, а все же арендовать.

Andreyka:
mount -o remount,noatime,nodiratime /blablabla

lealhost:
Включено журналирование файловой системы. Кстати, отключение его может существенно повысить производительность. :)

1004 be/3 root 0.00 B/s 11.63 K/s 0.00 % 31.27 % [jbd2/sda3-8]
995 be/3 root 0.00 B/s 31.01 K/s 0.00 % 8.48 % [jbd2/sda2-8]
986 be/3 root 0.00 B/s 27.14 K/s 0.00 % 6.07 % [jbd2/sda5-8]

12:56:44 1004 be/3 root 0.00 B/s 3.94 K/s 0.00 % 34.13 % [jbd2/sda3-8]
12:56:45 1004 be/3 root 0.00 B/s 0.00 B/s 0.00 % 42.64 % [jbd2/sda3-8]
12:56:46 1004 be/3 root 0.00 B/s 0.00 B/s 0.00 % 17.85 % [jbd2/sda3-8]
12:56:46 977 be/3 root 0.00 B/s 180.04 K/s 0.00 % 10.26 % [jbd2/sda8-8]
12:56:47 1004 be/3 root 0.00 B/s 19.63 K/s 0.00 % 45.85 % [jbd2/sda3-8]
12:56:48 1004 be/3 root 0.00 B/s 27.32 K/s 0.00 % 19.98 % [jbd2/sda3-8]
12:56:48 986 be/3 root 0.00 B/s 35.12 K/s 0.00 % 10.09 % [jbd2/sda5-8]
12:56:48 995 be/3 root 0.00 B/s 0.00 B/s 0.00 % 6.70 % [jbd2/sda2-8]
12:56:49 995 be/3 root 0.00 B/s 47.15 K/s 0.00 % 51.02 % [jbd2/sda2-8]
12:56:49 1004 be/3 root 0.00 B/s 102.16 K/s 0.00 % 44.55 % [jbd2/sda3-8]
12:56:50 1004 be/3 root 0.00 B/s 77.96 K/s 0.00 % 31.40 % [jbd2/sda3-8]
12:56:51 1004 be/3 root 0.00 B/s 19.70 K/s 0.00 % 20.49 % [jbd2/sda3-8]
12:56:51 977 be/3 root 0.00 B/s 94.54 K/s 0.00 % 19.37 % [jbd2/sda8-8]
12:56:52 1004 be/3 root 0.00 B/s 35.03 K/s 0.00 % 76.54 % [jbd2/sda3-8]
12:56:53 986 be/3 root 0.00 B/s 31.37 K/s 0.00 % 20.24 % [jbd2/sda5-8]
12:56:53 417 be/3 root 0.00 B/s 47.06 K/s 0.00 % 18.57 % [jbd2/sda6-8]
12:56:53 1004 be/3 root 0.00 B/s 3.92 K/s 0.00 % 10.79 % [jbd2/sda3-8]
12:56:53 995 be/3 root 0.00 B/s 70.59 K/s 0.00 % 9.07 % [jbd2/sda2-8]

tmpfs 12G 0 12G 0% /dev/shm
/dev/sda1 96M 85M 6.3M 94% /boot
/dev/sda8 664G 92G 539G 15% /home
/dev/sda5 29G 678M 27G 3% /tmp
/dev/sda2 99G 17G 77G 18% /usr
/dev/sda3 99G 19G 75G 20% /var

Vin_cent:
Я в конфиге mysql не увидел у вас путь к tmpdir (не диск должен быть, а память). Его нужно прописать.

Vin_cent:
Тут Большое пространство для тюнинга.

Со старта, сделайте:
1. 'tmpdir=/mnt/ramdisk':
> mkdir -p /mnt/ramdisk
> chown mysql:mysql /mnt/ramdisk
> mount -t tmpfs -o size=1024M tmpfs /mnt/ramdisk
#/etc/fstab
#tmpfs /mnt/ramdisk tmpfs rw,noatime,mode=1777,size=1024M 0 0

2.
max_heap_table_size=1024M
tmp_table_size=1024M

3. Проверить запросы с JOIN, там есть поля без индексов. Проставить индексы.

4.
slow-query-log
long_query_time=2
slow_query_log_file=/tmp/slow-queries-log
И мониторить этот лог, исправляя кривопопые (например без индексов) запросы.

[OK] Currently running supported MySQL version 5.5.40-cll
[OK] Operating on 64-bit architecture

-------- Storage Engine Statistics -------------------------------------------
[--] Status: +ARCHIVE +BLACKHOLE +CSV -FEDERATED +InnoDB +MRG_MYISAM
[--] Data in MyISAM tables: 2G (Tables: 18722)
[--] Data in InnoDB tables: 439M (Tables: 7579)
[--] Data in PERFORMANCE_SCHEMA tables: 0B (Tables: 17)
[--] Data in MEMORY tables: 5M (Tables: 250)
[!!] Total fragmented tables: 820


-------- Performance Metrics -------------------------------------------------
[--] Up for: 7d 14h 50m 54s (128M q [194.690 qps], 5M conn, TX: 704B, RX: 20B)
[--] Reads / Writes: 68% / 32%
[--] Total buffers: 256.0M global + 4.5M per thread (500 max threads)
[OK] Maximum possible memory usage: 2.4G (10% of installed RAM)
[OK] Slow queries: 0% (704/128M)
[OK] Highest usage of available connections: 9% (45/500)
[OK] Key buffer size / total MyISAM indexes: 32.0M/1.4G
[OK] Key buffer hit rate: 99.8% (20B cached / 45M reads)
[OK] Query cache efficiency: 73.2% (67M cached / 92M selects)
[!!] Query cache prunes per day: 1147838
[OK] Sorts requiring temporary tables: 0% (42K temp sorts / 7M sorts)
[!!] Joins performed without indexes: 236783
[!!] Temporary tables created on disk: 27% (1M on disk / 6M total)
[OK] Thread cache hit rate: 99% (45 created / 5M connections)
[!!] Table cache hit rate: 0% (500 open / 125M opened)
[OK] Open file limit used: 1% (877/50K)
[OK] Table locks acquired immediately: 99% (48M immediate / 48M locks)
[!!] InnoDB buffer pool / data size: 128.0M/439.8M
[OK] InnoDB log waits: 0
-------- Recommendations -----------------------------------------------------
General recommendations:
Run OPTIMIZE TABLE to defragment tables for better performance
Enable the slow query log to troubleshoot bad queries
Adjust your join queries to always utilize indexes
When making adjustments, make tmp_table_size/max_heap_table_size equal
Reduce your SELECT DISTINCT queries without LIMIT clauses
Increase table_open_cache gradually to avoid file descriptor limits
Read this before increasing table_open_cache over 64: http://*******/1mi7c4C
Variables to adjust:
query_cache_size (> 64M)
join_buffer_size (> 2.0M, or always use indexes with joins)
tmp_table_size (> 16M)
max_heap_table_size (> 16M)
table_open_cache (> 500)
innodb_buffer_pool_size (>= 439M)

[mysqldump]
quick
max_allowed_packet=16M
[myisamchk]
read_buffer=16M
key_buffer=64M
write_buffer=16M
sort_buffer=32M
[mysqld]
join_buffer_size=2M
default-storage-engine=MyISAM
connect_timeout=60
max_connect_errors=10
max_allowed_packet=268435456
wait_timeout=180
query_cache_limit=2M
innodb_file_per_table=1
interactive_timeout=180
table_cache=500
max_user_connections=100
query_cache_size=64M
key_buffer=32M
query_cache_type=1
open_files_limit=50000
sort_buffer_size=1M
myisam_sort_buffer_size=32M
max_connections=500
read_buffer_size=1M
thread_cache_size=128
innodb_buffer_pool_size=134217728
[mysql]
no-auto-rehash

twinlv:
Сделайте отдельную виртуалку с mysql и конектитесь к ней а не к локальной. Нагрузка упадет.