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I am trying to partition a table with 200 million records in it. This table already exists:

CREATE TABLE linkmap_ntoken (
  target_nToken varchar(200) NOT NULL,
  ntoken_hashcode int(15) NOT NULL,
  targeturl varchar(2000) NOT NULL,
  targetbreadcrumb varchar(400) NOT NULL,
  sourceurl varchar(2000) NOT NULL,
  sourcebreadcrumb varchar(400) NOT NULL
 ) ENGINE=InnoDB. 

Now I am trying to create 500 partition with this statement.

ALTER TABLE linkmap_ntoken partition by HASH (ntoken_hashcode) partitions 500;

And it throws exception as total number of locks exceeded the lock table size.

I read few suggestions online and changed my.cnf file.Here are the configurations:

# bit high but I got tons of ram here #
sort_buffer_size                = 2M
read_buffer_size                = 2M
binlog_cache_size               = 1M
wait_timeout                    = 31536000
interactive_timeout             = 300
max_allowed_packet              = 12M
thread_stack                    = 128K
table_cache                     = 1024
myisam_sort_buffer_size         = 1M
tmp_table_size                  = 12M
max_heap_table_size             = 12M

log_queries_not_using_indexes  = 1
slow_query_log                 = 1
slow_query_log_file            = /var/lib/mysql/slowquery.log

# MyISAM #
key_buffer_size                = 32M
myisam_recover                 = FORCE,BACKUP

max_allowed_packet             = 16M
max_connect_errors             = 1000000

log_bin                        = /var/lib/mysql/mysql-bin
expire_logs_days               = 14
sync_binlog                    = 1

tmp-table-size                 = 32M
max-heap-table-size            = 32M
query-cache-type               = 0
query-cache-size               = 0
max-connections                = 500
thread-cache-size              = 50
open-files-limit               = 65535
table-definition-cache         = 1024
table-open-cache               = 2048

innodb-flush-method            = O_DIRECT
innodb-log-files-in-group      = 2
innodb-log-file-size           = 512M
innodb-flush-log-at-trx-commit = 1
innodb-file-per-table          = 1
innodb-buffer-pool-size        = 40G

I have restarted mysql after making these changes. Still it throws the exception. My server has 12 cores and 48GB Ram and I can dedicate this server for this partitioning process for time being. are there any suggestions to bypass this exception(total number of locks exceeded)?

share|improve this question
The only variable relevant to this error is innodb_buffer_pool_size because that's where the table of lock structures lives. The first step might be to SHOW GLOBAL VARIABLES LIKE 'innodb_buffer_pool_size'; to verify that your configuration is actually setting the pool as large as you intend... but also, what are you thinking messing around with partitioning on such a relatively small table when you don't even have a primary key or any indexes? –  Michael - sqlbot Jan 25 at 5:37
when I did show global variables, it is showing buffer pool size as 8388608. And regarding your question about why partitioning, I do not have a unique column to have a primary key. Even If I add one I wont be able to query with it. I am using this table to query for a online application. I want my query to return results in less than a second. –  user2611221 Jan 26 at 7:20
I think I need to make changes with in [mysqld] block for my changes to take effect. let me try that. Thanks for pointing that out. –  user2611221 Jan 26 at 7:42
I changed innodb_buffer_pool_size under [mysqld] block and restarted. It doesn't seems to be effected. It is still 8388608. –  user2611221 Jan 27 at 14:16

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