…_per_table = 1 ## Disabling query cache query_cache_size = 0 query_cache_type = 0 You can see that the buffer pool is sized at 55G and I am… performance. Other then that, I have also disabled query cache to avoid contention caused by query cache on write heavy workload. OK, so that… to reduce chances of log flush storms and disabling the query cache.
Comment: Announcement of Percona XtraDB Cluster 5.5.20 GA release
May 1, 2012 By 10 Comments
… all of the configuration go for example default_storage_engine, query_cache_size, e.t.c…. Is it something built in or we…
Comment: Too many connections? No problem!
March 15, 2012 By 28 Comments
…-slow-queries=/var/log/mysql-slow-queries.log long_query_time=15 log-queries-not-using-indexes query_cache_type=1 query_cache_size=32M thread_cache_size=30 table_cache=4096 join_buffer_size=6M key_buffer_size…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
…) with a Scale Factor of 2 (InnoDB dataset size ~5G). Note that query cache is disabled during these benchmark runs and that the…_size increased to 6M, the query time was ~300s while when both the join_buffer_size and the read_rnd_buffer_size/mrr_buffer_size were set to 6M, the query time dropped to ~40s…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
I have been working with Peter in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a look at and benchmarking optimizer enhancements one by one. So in the same way this blog post is aimed at a new optimizer enhancement Index Condition …
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
… a different variable to control the MRR buffer size mrr_buffer_size. Both buffer sizes default to 256K in MySQL 5.6 and… 2 (InnoDB dataset size ~5G). I did not use Scale Factor of 40 (InnoDB dataset size ~95G), because the query was taking far… of MySQL 5.6 and MariaDB 5.5. Note that query cache is disabled during these benchmark runs and that the disks…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
… for query execution, which size can be controlled by tmp_table_size and which also only exist for duration of query execution …Adaptive hash index 4422068288 (2039977928 + 2382090360) Page hash 127499384 Dictionary cache 512619219 (509995888 + 2623331) File system 294352 (82672 + 211680) Lock …
Post: Beware large Query_Cache sizes
March 23, 2007 By 3 Comments
… ? If you set query_cache_size relatively high at 256MB or more. It can be seen worse if your query cache size is in Gigabytes. At the same time check how many queries do you have in cache – Qcache_queries_in_cache – if it… to solve the problem ? The easiest solution is to decrease query cache size – smaller values do not have such problems but also often…
Post: table_cache negative scalability
November 16, 2009 By 23 Comments
… – we’ve seen performance issues with large query_cache_size also sort_buffer_size and read_buffer_size may not give you better performance if… well cached so the cost of table cache miss is not very high, you may be better of with significantly reduced table cache size… – in this version table_cache was significantly redone and split in table_open_cache and table_definition_cache and I assumed the behavior…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
… Queriesblogpercona.commanual query_alloc_block_sizeblogpercona.commanual query_cache_limitblogpercona.commanual query_cache_min_res_unitblogpercona.commanual query_cache_sizeblogpercona.commanual query_cache_typeblogpercona.commanual query_cache_wlock_invalidateblogpercona.commanual query_prealloc…
