MySQL consuming all system memory on INSERT ... SELECT
- by siete
The mysql daemon is getting killed because Linux is reaching out of memory:
Oct 24 07:41:23 <hostname> kernel: [82297.673701] Out of memory: kill process 13816 (mysqld) score 1839626 or a child
There is a link with some workaround on this.
That only happen when executing a query INSERT ... SELECT with a very huge resulset.
MySQLTuner script displays that maximum theorical memory is less than 8GB, but top and munim shows that is getting over all RAM and swap available:
[--] Total buffers: 560.0M global + 72.2M per thread (100 max threads)
[OK] Maximum possible memory usage: 7.6G (43% of installed RAM)
I'm tried to tune some options with not results, there are the relevant ones:
skip-locking
max_connections = 100
key_buffer_size = 512M
max_allowed_packet = 32M
table_open_cache = 2000
open_files_limit = 3000
sort_buffer_size = 16M
read_buffer_size = 16M
read_rnd_buffer_size = 8M
myisam_sort_buffer_size = 64M
thread_cache_size = 4
query_cache_size = 16M
query_cache_limit = 2M
thread_concurrency = 4
join_buffer_size = 32M
tmp_table_size = 32M
max_heap_table_size = 32M
query_cache_limit = 8M
bulk_insert_buffer_size = 64M
myisam_max_sort_file_size = 50GB
myisam_mmap_size = 10GB
And there is a system resume:
OS: Linux Debian "Squeeze" 6.0.8 (upgraded yesterday)
RAM: 18GB
Swap: 18GB
MySQL: 5.1.72-2 (official Debain release)
At this moment, update or change OS or MySQL version is not possible, there is any option that can help and i missed?
Sorry by my english, and thank you in advance!
Edit: I'm only using MyISAM tables, and cannot change to InnoDB.