Hi,
MYSQL 3.23.39 on Linux 7.3 is returning an error 12 while creating temporary
tables. Application works fine as long as RAM is available, and fails when
free memory becomes less than 25MB. Temp tables are not bigger than 23 MB.
We are reluctant to use tmp_table_size/big_tables for performance reasons.
Errors:
1. [TCX][MyODBC]Got error 12 from table handler
* perror 12 say: Error code 12: Cannot allocate memory
2. [TCX][MyODBC]Out of memory (Needed 400 bytes)
I understand, that, there is not enough memory. The server has 8GB SWAP;
however ZERO size is being used. We have tried all sorts of swap commands
(mkswap, swapon, swapoff) to setup SWAP partitions as well as swap file. It
didn't work.
Anyone is using 8GB RAM with 8GB/16GB SWAP?
Any info why MYSQL is not using SWAP?
Is there limitation on memory usage by MYSQL?
http://www.spack.org/index.cgi/LinuxRamLimits
<http://www.spack.org/index.cgi/LinuxRamLimits>
Above article explains about Kernel limitation to use bigger memory. Is it
true anymore? Is there MYSQL parameter to setup to use bigger memory?
-------System info----------------------
Server: Quad (8 partitioned) Xeon 2.0GHz, 8GB RAM, 8GB SWAP, 200GB RAID.
Four 2GB separate partitions for swap.
OS: Linux 2.4.18-26.7
Database: MYSQL 3.23.39 Binary install
-------top command output -----------------
Mem: 7483272K av, 7023340K used, 459932K free, 0K shrd, 96448K
buff
Swap: 8388544K av, 0K used, 2097136K free 5443376K
cached
Note: Gives error 12 as soon as memory free becomes less than 25MB.
----------------------Mysql.cnf ------------------
set-variable = key_buffer=4096M
set-variable = max_allowed_packet=1M
set-variable = table_cache=1024
set-variable = max_connections=256
set-variable = sort_buffer=400M
set-variable = join_buffer=64M
set-variable = tmp_table_size=100M
set-variable = record_buffer=256M
set-variable = myisam_sort_buffer_size=512M
set-variable = thread_cache=8
set-variable = thread_concurrency=4
set-variable = myisam_max_extra_sort_file_size=512M
set-variable = myisam_max_sort_file_size=512M
set-variable = max_connect_errors=999999999
tmpdir = /home1/mysql/tmp # 36GB SCSI disk.
--------------end cnf---------------
