…, free, fast-paced and very technical MySQL educational event for wide range of people interested in MySQL – Developers, System Administrators, DBAs, etc. It will be held at Portland State University’s Smith Memorial Student Union… to the cities showing greatest interest. As usual space is limited, so Register Now!
Post: MySQL and the SSB - Part 2 - MyISAM vs InnoDB low concurrency
May 22, 2013 By Leave a Comment
… threads) with fast IO (OCZ R4 1.6TB) and 128GB memory. For the hot test, the data fits in the buffer…!. MyISAM may be good for raw performance, but there are limitations which MyISAM imposes that are difficult to work with. MyISAM… the working set fits in memory, InnoDB almost always performs better, at least for this workload. Notes MySQL version used: 5.6…
Post: Choosing a MySQL HA Solution - Post-Webinar Q&A
June 7, 2013 By Leave a Comment
… master. This can be useful if you’re trying to limit the amount of data sent over the wire, but it… that trouble is brewing. Or if you watch your MySQL server’s memory usage and you see that it’s starting to…: Incorrect information in file: ‘./mysql/servers.frm’ ERROR: 1033 Incorrect information in file: ‘./mysql/servers.frm’ Running mysql_install_db under strace, I…
Comment: ZFS on Linux and MySQL
May 31, 2013 By 17 Comments
… see this writeup on ZFS and MySQL. One question, why with 192GB of memory, did you limit the ARC to 4GB? Also wondering if any one is using ZFS and MySQL to thin…. Would be interested if someone wanted to contribute on the MySQL side. Interesting that on Wikipedia Data Virtualization is talked about…
Post: Galera Flow Control in Percona XtraDB Cluster for MySQL
May 2, 2013 By 5 Comments
… in a master/slave cluster might be: mysql> set global wsrep_provider_options=”gcs.fc_limit=500; gcs.fc_master_slave=YES… cost of increasing the fc_limit Keeping the fc_limit small has two three purposes: It limits the amount of delay any node… a hash table. A small fc_limit does however keep the certification index smaller in memory. It keeps the certification interval small…
Post: Memory allocators: MySQL performance improvements in Percona Server 5.5.30-30.2
April 15, 2013 By
…) memory allocation is an costly operation and if memory allocator has scalability problems (like allocator from glibc) this will notably slowdown MySQL-transaction… and jemalloc allocators. Observations: = MySQL 5.5.30 – throughput of MySQL 5.5.30 with glibc is limited first of all by inefficiency…
Post: trx descriptors: MySQL performance improvements in Percona Server 5.5.30-30.2
April 12, 2013 By 3 Comments
… states is then a matter of copying a relatively small memory block which, depending on many factors, can be from few… to the following kinds of transactions: MySQL transactions started with START TRANSACTION READ ONLY MySQL transactions created by a non-locking SELECT… read-only optimization in MySQL 5.6 to achieve even better scalability while removing the read-only limitations. Let’s take a…
Post: Is Synchronous Replication right for your app?
May 14, 2013 By 18 Comments
… or work around it with by fsyncing to memory (Battery or capacitor-backed write cache), etc…standard MySQL replication from this instance, since MySQL replication is asynchronous. What about semi-sync MySQL replication… This means more waiting, and after the limit is exceeded you will still get the…
Post: The write cache: Swap insanity tome III
April 19, 2013 By 5 Comments
…. In summary, you need to interleave the allocation of memory for the MySQL process using the numactl utility, drop the file cache… was especially puzzling since MySQL was not involved. The server was running with nearly 7GB of free memory but the push to… backup size is about 28GB and the file upload size limit is 5GB. So, about 28GB was written to disk in…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 5 Comments
… MySQL in wild. I also wanted to share some troubleshooting techniques I use. Plot Memory Usage First I would like to see MySQL memory consumption plotted. I use “VSZ” columns from “ps” output on Linux. It helps me to understand how this memory allocation…_heap_table_size variable which allows you to limit size of MEMORY tables (the limit applies both to implicit and explicit ones) but…
