tuning.cnf

[mysqld]
max_allowed_packet = 16M

# Sort buffer is used to perform sorts for some ORDER BY and GROUP BY
# queries. If sorted data does not fit into the sort buffer, a disk
# based merge sort is used instead - See the "Sort_merge_passes"
# status variable. Allocated per thread if sort is needed.
# Comment out for now, the default in MariaDB 10.2 is 2M
#sort_buffer_size = 1M

# Size of the buffer used for doing full table scans.
# Allocated per thread, if a full scan is needed.
read_buffer_size = 1M

# When reading rows in sorted order after a sort, the rows are read
# through this buffer to avoid disk seeks. You can improve ORDER BY
# performance a lot, if set this to a high value.
# Allocated per thread, when needed.
read_rnd_buffer_size = 8M

join_buffer_size = 8M # should be equal to read_rnd_buffer_size?

# Maximum allowed size for a single HEAP (in memory) table. This option
# is a protection against the accidential creation of a very large HEAP
# table which could otherwise use up all memory resources.
max_heap_table_size = 64M
tmp_table_size = 64M # Should be equal to max_heap_table_size

## Generally, it is unwise to set the query cache to be larger than 64-128M
## as the costs associated with maintaining the cache outweigh the performance
## gains.
## The query cache is a well known bottleneck that can be seen even when
## concurrency is moderate. The best option is to disable it from day 1
## by setting query_cache_size = 0 (now the default on MySQL 5.6)
## and to use other ways to speed up read queries: good indexing, adding
## replicas to spread the read load or using an external cache.
query_cache_type = on
query_cache_size  = 32M
query_cache_strip_comments = on
query_cache_min_res_unit = 2K
# query_cache_limit = 256K # Default is 1M now

thread_cache_size = 16
table_open_cache = 4096
table_definition_cache = 1024

#
# InnoDB
#
# The buffer pool is where data and indexes are cached: having it as large as possible
# will ensure you use memory and not disks for most read operations.
# Typical values are 50..75% of available RAM.
innodb_buffer_pool_size = 768M # 75% of 1GB RAM
innodb_log_file_size = 192M # 25% of innodb_buffer_pool_size
innodb_flush_method	= O_DIRECT

# This setting should be set to 0 (disabled) on SSDs which do not have
# any performance gains with sequential IO.
innodb_flush_neighbors = 0

# The default setting of 1 means that InnoDB is fully ACID compliant.
# It is the best value when your primary concern is data safety, for instance on a master.
# However it can have a significant overhead on systems with slow disks because of the
# extra fsyncs that are needed to flush each change to the redo logs.
# Setting it to 2 is a bit less reliable because committed transactions will be
# flushed to the redo logs only once a second, but that can be acceptable on some situations
# for a master and that is definitely a good value for a replica. 0 is even faster
# but you are more likely to lose some data in case of a crash: it is only a good value for a replica.
innodb_flush_log_at_trx_commit = 0

# Conquer an InnoDB crash with `InnoDB: A long semaphore wait` error
# See http://stackoverflow.com/questions/24860111/warning-a-long-semaphore-wait
# See http://www.markleith.co.uk/2009/05/13/innodb_stats_on_metadata-innodb_adaptive_hash_index/
innodb_adaptive_hash_index = off

# Kill iddle connections after 10min
wait_timeout = 600

[mysqldump]
max-allowed-packet = 16M