I am database novice.
I recently upgraded to version 1.8.
The following are red flags( the value parameters are in red) on my MYSQL database. I would be greatful if I could get some simple instructions or scripts to run on fixing these problems. Thanks in advance.
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Slow_queries 53 k The number of queries that have taken more than long_query_time seconds. MySQL - Documentation
Handler_read_rnd 1,229 M The number of requests to read a row based on a fixed position. This is high if you are doing a lot of queries that require sorting of the result. You probably have a lot of queries that require MySQL to scan whole tables or you have joins that don't use keys properly.
Handler_read_rnd_next 4,043.72 M The number of requests to read the next row in the data file. This is high if you are doing a lot of table scans. Generally this suggests that your tables are not properly indexed or that your queries are not written to take advantage of the indexes you have.
Qcache_lowmem_prunes 35 M The number of queries that have been removed from the cache to free up memory for caching new queries. This information can help you tune the query cache size. The query cache uses a least recently used (LRU) strategy to decide which queries to remove from the cache.
Created_tmp_disk_tables 1,339 k The number of temporary tables on disk created automatically by the server while executing statements. If Created_tmp_disk_tables is big, you may want to increase the tmp_table_size value to cause temporary tables to be memory-based instead of disk-based.
Select_full_join 1,081 k The number of joins that do not use indexes. If this value is not 0, you should carefully check the indexes of your tables.
Select_range_check 3,738 The number of joins without keys that check for key usage after each row. (If this is not 0, you should carefully check the indexes of your tables.)
Sort_merge_passes 748 The number of merge passes the sort algorithm has had to do. If this value is large, you should consider increasing the value of the sort_buffer_size system variable.
Opened_tables 6,595 k The number of tables that have been opened. If opened tables is big, your table cache value is probably too small.
Table_locks_waited 60 M The number of times that a table lock could not be acquired immediately and a wait was needed. If this is high, and you have performance problems, you should first optimize your queries, and then either split your table or tables or use replication.
