090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)
090504 6:51:05 [ERROR] /usr/local/mysql/libexec/mysqld: Out of memory (Needed 1676960 bytes)

最有可能是进程空间不足引起，参考http://dev.mysql.com/doc/refman/5.1/en/freebsd.html 。

OS是FreeBSD 6.4 - p4 ：
echo "kern.maxdsiz=\"1073741824\"" >>/boot/loader.conf
echo "kern.dfldsiz=\"1073741824\"" >>/boot/loader.conf
echo "kern.maxssiz=\"134217728\"" >>/boot/loader.conf
reboot