This post comes from Vadim Tkachenko at the MySQL Performance Blog.
This post is a continuation of my research into TokuDB’s storage engine to understand if it is suitable for timeseries workloads.
While inserting LOAD DATA INFILE into an empty table shows great results for TokuDB, it would be more interesting to see some realistic workloads.
So this time let’s take a look at the INSERT benchmark.
What I am going to do is insert data in 16 parallel threads into the table from the previous post:
CREATE TABLE `sensordata` ( `ts` int(10) unsigned NOT NULL DEFAULT '0', `sensor_id` int(10) unsigned NOT NULL, `data1` double NOT NULL, `data2` double NOT NULL, `data3` double NOT NULL, `data4` double NOT NULL, `data5` double NOT NULL, `cnt` int(10) unsigned NOT NULL, PRIMARY KEY (`sensor_id`,`ts`) )
The inserts are bulk inserts with sequentially increasing
ts and with
sensor_id from 1 to 1000.
While the inserts are not fully sequential, because the primary key is
(sensor_id, ts), it is enough to have in memory workload, so I do not expect performance degradation when data exceeds memory. This will play in favor for InnoDB, as it is known that TokuDB performs worse in CPU-bound benchmarks.
The benchmark executes one million events, each event inserts 1,000 records in bulk. When it's finished we should have about one billion records in the table.
So InnoDB comes with the following numbers:
- InnoDB with no compression averages at 350 inserts per second with a response time of 80-100 ms per transaction. The final table size is 82 GB
- InnoDB with 8K compression has a throughput of 130 inserts per second with a response time 250 ms. The final table size is 60 GB
Now, we have a pretty bad compression rate because I used uniform distribution for values of data1-data5 columns, and uniform may not be good for compression. And, actually, in the real case I expect much more repeating values, so I am going to re-test with pareto (zipfian) distribution.
For TokuDB (tested tokudb_fast and tokudb_small formats):
- After an initial warmup, TokuDB shows quite inconsistent performance with both tokudb_fast and tokudb_small formats.
- For tokudb_fast, the throughput is topping at ~150 inserts per second, and 95% response time at ~160 ms. However, there are periodical stalls when throughput drops almost to zero and response times jump to 10 seconds (!!!) per transaction.
- For tokudb_small, the throughput is even less stable jumping around 100 inserts per second and response times start at 300 ms per transaction, with stalls up to 30 seconds per transaction
File sizes for TokuDB:
- tokudb_fast: 50 GB
- tokudb_small: 45 GB.
Again, I correspond a bad compression rate to uniform distribution. If we switch to pareto, the file size for tokudb_fast is 21 GB, and tokudb_small is 13 GB
Now, I consider these stalls in TokuDB as severe and I do not think I can recommend using it in production under such workload conditions until the problem is fixed.
You can find the scripts for the timeseries benchmark for sysbench v0.5 here.
Software versions for InnoDB: Percona Server 5.6-RC3, for TokuDB: mariadb-5.5.30-tokudb-7.0.4
UPDATE (September 5, 2013):
By many requests I'm updating the post with following information:
TokuDB throughput (tokudb_small row format) with Pareto distribution, for two cases:
- 1. PRIMARY KEY (
ts) (on graph:
- 2. PRIMARY KEY (
sensor_id), KEY (
ts) (on graph:
We can see that the top throughput for
tokudb_small_key is less than for
tokudb_small, but there is also less variance in throughput.
The my.cnf Files
[mysqld] # gdb log-error=error.log innodb_file_per_table = true innodb_data_file_path = ibdata1:100M:autoextend innodb_flush_method = O_DIRECT innodb_log_buffer_size = 256M innodb_flush_log_at_trx_commit = 1 innodb_buffer_pool_size = 40G innodb_buffer_pool_instances=1 innodb_file_format = Barracuda innodb_checksum_algorithm = crc32 innodb_log_file_size = 4G innodb_log_files_in_group = 2 #innodb_log_block_size=4096 #####plugin options innodb_read_io_threads = 16 innodb_write_io_threads = 4 innodb_io_capacity = 4000 #not innodb options (fixed) port = 3306 back_log = 50 max_connections = 2000 max_prepared_stmt_count=500000 max_connect_errors = 10 table_open_cache = 2048 max_allowed_packet = 16M binlog_cache_size = 16M max_heap_table_size = 64M sort_buffer_size = 4M join_buffer_size = 4M thread_cache_size = 1000 query_cache_size = 0 query_cache_type = 0 thread_stack = 192K tmp_table_size = 64M server-id = 10 key_buffer_size = 8M read_buffer_size = 1M read_rnd_buffer_size = 4M bulk_insert_buffer_size = 8M myisam_sort_buffer_size = 8M myisam_max_sort_file_size = 10G myisam_repair_threads = 1 myisam_recover socket=/var/lib/mysql/mysql.sock user=root
For TokuDB (pretty much default):
[mysqld] gdb skip-innodb #not innodb options (fixed) port = 3306 back_log = 50 max_connections = 2000 max_prepared_stmt_count=500000 max_connect_errors = 10 table_open_cache = 2048 max_allowed_packet = 16M binlog_cache_size = 16M max_heap_table_size = 64M sort_buffer_size = 4M join_buffer_size = 4M thread_cache_size = 1000 query_cache_size = 0 query_cache_type = 0 ft_min_word_len = 4 #default_table_type = InnoDB thread_stack = 192K tmp_table_size = 64M server-id = 10 key_buffer_size = 8M read_buffer_size = 1M read_rnd_buffer_size = 4M bulk_insert_buffer_size = 8M myisam_sort_buffer_size = 8M myisam_max_sort_file_size = 10G #myisam_max_extra_sort_file_size = 10G myisam_repair_threads = 1 myisam_recover socket=/var/lib/mysql/mysql.sock user=root