… The cache devices were flushed to disk …cache” test run as well using the base HDD MySQL…cached (i.e., no special treatment of sequential writes… dirty-page ratios on device performance…cache_size = 0 query_cache_type = 0 ft_min_word_len = 4 thread_stack = 192K tmp_table_size = 64M serverid = 101 key…
Post: What MySQL buffer cache hit rate should you target
June 29, 2006 By 5 Comments
… case global key hit ratio may be 99.99% but you would still have problems with key buffer efficiency….writes, how good was OS or SAN cache hit rate – something you would not see otherwise. The bad luck is – MySQL… of them make it to the disk. In some configurations OS cache may take all of them. In…
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
…writes to the same page, then fewer disk writes are needed. But if your write…disk controller write-back cache does the same thing. PZ: First Indeed writes are slower with Flash disks… etc). But the ratio of RAM used for these non-mysql …/s HT: Strange, primary key equality searches should work…
Post: What to tune in MySQL Server after installation
September 29, 2006 By 118 Comments
… as MySQL DBAs or be involved with MySQL … incremental performance improvements. key_buffer_size – Very …size Very important for write intensive workloads especially for…disk but only flush it to OS cache. The log is still flushed to the disk…. For certain workloads cache hit ratio is lower than…
Post: MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark
March 11, 2013 By 7 Comments
… 4 disk 7200RPM RAID 10 array with 512MB write-back cache Star Schema Benchmark – Scale Factor 1 – Mysql 5.5…a lower buffer pool hit ratio during the MySQL 5.6 runs and MySQL 5.6.10 was doing… C_MktSegment varchar(10), KEY(C_Name), KEY(C_City), KEY(C_Region), KEY(C_Phone), KEY(C_MktSegment) ); DROP …
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
…gets over 16:1 compression ratio(compared to Innodb, 8:…. This frees disk to use on-disk temporary storage for … innodb-write-io-threads=4 join-buffer-size=16M key-…cache=16384 table-open-cache=128 thread-cache-size=32 thread-stack=256K tmp-table-size=64M transaction-isolation=READ-COMMITTED user=mysql…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…MySQL thread id 9697561, query id 188161264 localhost root update insert into child values(2,2) Foreign key… For writes Innodb has to ensure data makes it to the disk – just passing it to OS cache is…pool. Finally you can see buffer pool hit ratio which measures buffer pool efficiency. 1000/1000 …
