How to change the read/write ratio of sysbench oltp_read_write script - sysbench

Question

I'm using the sysbench(1.1.0) to test the performance of MySQL, and I want to test the scene that read:write is 95%:5%. Are there any parameters to change the read/write ratio?

Answer 1

You can have a look at the oltp_read_write script:
function event()
if not sysbench.opt.skip_trx then
begin()
end
execute_point_selects()
if sysbench.opt.range_selects then
execute_simple_ranges()
execute_sum_ranges()
execute_order_ranges()
execute_distinct_ranges()
end
execute_index_updates()
execute_non_index_updates()
execute_delete_inserts()
if not sysbench.opt.skip_trx then
commit()
end
check_reconnect()
end
This script define the query in a transaction, and the options are below(sysbench oltp_read_write.lua help):
oltp_read_write.lua options:
--auto_inc[=on|off] Use AUTO_INCREMENT column as Primary Key (for MySQL), or its alternatives in other DBMS. When disabled, use client-generated IDs [on]
--create_secondary[=on|off] Create a secondary index in addition to the PRIMARY KEY [on]
--create_table_options=STRING Extra CREATE TABLE options []
--delete_inserts=N Number of DELETE/INSERT combinations per transaction [1]
--distinct_ranges=N Number of SELECT DISTINCT queries per transaction [1]
--index_updates=N Number of UPDATE index queries per transaction [1]
--mysql_storage_engine=STRING Storage engine, if MySQL is used [innodb]
--non_index_updates=N Number of UPDATE non-index queries per transaction [1]
--order_ranges=N Number of SELECT ORDER BY queries per transaction [1]
--pgsql_variant=STRING Use this PostgreSQL variant when running with the PostgreSQL driver. The only currently supported variant is 'redshift'. When enabled, create_secondary is automatically disabled, and delete_inserts is set to 0
--point_selects=N Number of point SELECT queries per transaction [10]
--range_selects[=on|off] Enable/disable all range SELECT queries [on]
--range_size=N Range size for range SELECT queries [100]
--reconnect=N Reconnect after every N events. The default (0) is to not reconnect [0]
--secondary[=on|off] Use a secondary index in place of the PRIMARY KEY [off]
--simple_ranges=N Number of simple range SELECT queries per transaction [1]
--skip_trx[=on|off] Don't start explicit transactions and execute all queries in the AUTOCOMMIT mode [off]
--sum_ranges=N Number of SELECT SUM() queries per transaction [1]
--table_size=N Number of rows per table [10000]
--tables=N Number of tables [1]
So, the default read/write ratio is 10+4/1+1+2+2, and you can change the read/write ratio just by changing the option number. For example:
sysbench oltp_read_write.lua --range_selects=off --point_selects=100 xxx
Then the read/write ratio is 100+4/1+1+2+2.