… you will run out of file descriptors. “table_cache” is what defines how many tables will be opened and you can configure… kept open permanently which can waste a lot of memory but it is other problem. Speaking about “open_file_limit” which limits number of files MySQL can… it to rather high values. I used MySQL with other 100.000 of files opened at the same time with no problems. Shutdown…
Post: Filling the tmp partition with persistent connections
August 6, 2012 By 14 Comments
… than disk space so those kind of partitions are very limited in size and there are some cases were we can… [...] /dev/loop0 985M 961M 0 100% /tmp Lets see which files has MySQL opened: # lsof -p 6112|grep ML mysqld 6112 root 38u… killing system in the end. Conclusion MySQL can creates temporary files even thought those temporary files are not visible on the EXPLAIN or…
Comment: How fast is FLUSH TABLES WITH READ LOCK?
February 24, 2012 By 30 Comments
FLUSH TABLES WITH READ LOCK; also tries to close open files that obviously takes time too. I did not double check … http://www.geeksww.com/tutorials/database_management_systems/mysql/installation/mysql_tablecache_informationschema_and_open_files_limit.php says so. However, the things I do…
Post: How to debug long-running transactions in MySQL
March 8, 2011 By 6 Comments
…a long-running transaction. If a transaction remains open for a very long time without committing, ….processlist p on b.trx_mysql_thread_id = p.ID LIMIT 1′) if [ "${host}" ]; then echo “Host …tcpdump –no-report –print” on the resulting tcpdump file (after inspecting the captured SHOW INNODB STATUS …
Comment: Cache Performance Comparison
August 10, 2006 By 74 Comments
… it as plain files (as “/path/[chunkid]/[wordid]/vec.txtâ€? for example) would then hit the max open files limit which exists in many operating systems while storing it as blobs in mysql would only use 3 file handles (or how many mysql… something like 100.000 files in a single directory or more. A third thing is that storing in mysql you can have…
Comment: More on table_cache
September 7, 2010 By 7 Comments
@Jay Pipes, I agree with you its only a MyISAM specific issue for the most part. Another reason for using a smaller table_cache http://www.geeksww.com/tutorials/database_management_systems/mysql/installation/mysql_tablecache_informationschema_and_open_files_limit.php
Comment: table_cache negative scalability
September 7, 2010 By 23 Comments
we recently faced a similar issue so I wrote a tutorial here –> http://www.geeksww.com/tutorials/database_management_systems/mysql/installation/mysql_tablecache_informationschema_and_open_files_limit.php
Comment: table_cache negative scalability
November 17, 2009 By 23 Comments
Also, On setting table_cache online. Most time you can decrease it online, however increasing it may cause issues because MySQL will not change the number of open files limit in this case.
Comment: What to tune in MySQL Server after installation
March 10, 2007 By 118 Comments
MySQL – Standardkonfiguration (InnoDB)… Server Open File Limit > 10000 coredumps müssen funktionieren /etc/my.cnf Gute Referenz:…
Post: 10+ Ways to Crash or Overload MySQL
November 13, 2007 By 20 Comments
…MySQL server to run out of file descriptors. The same is true for Partitioned tables in MySQL… as temporary tables, so by opening large amount of cursors which …MySQL does not have much of resource utilization control you can simply run heavy queries to get MySQL Server barely functional. The limits…
