… PXC for HP Cloud DNS. The post focuses on the key aspects of synchronous replication setup with high-availability guarantees like… up), which may not be feasible in a cloud environment. Next, the SST. Xtrabackup SST is used there. SST matters a…
Post: Percona XtraDB Cluster (PXC) in the real world: Share your use cases!
June 17, 2013 By Leave a Comment
Post: MySQL Query Patterns, Optimized - Webinar questions followup
June 3, 2013 By 2 Comments
… query in a suboptimal form. Q: Doesn’t the primary key solution for random selection only work when the IDs for…, and making lookups to the `kind_types` table by primary key, the result was a query that took half the time…. Join Percona and the MySQL community at our events. The next one is in London on November 11-12, 2013. We…
Post: Percona XtraDB Cluster for MySQL and encrypted Galera replication
May 3, 2013 By 2 Comments
… cert.pem Generating a 2048 bit RSA private key …………..+++ ……………………………………………………….+++ writing new private key to ‘key.pem’ —– You are about to be asked to… currently need to use the same cert and key on every node, so our next step is to copy these files to…
Post: Finally. How to verify if all MySQL records were recovered
April 25, 2013 By Leave a Comment
… in an unidirectional list. The list is sorted by primary key and starts with the internal record infinum and ends with… offset: 0×70 Next record at offset: 0x7F (127) Next record at offset: 0xA8 (168) Next record at offset: 0xCE (206) … Next record at offset…
Post: Is your MySQL buffer pool warm? Make it sweat!
April 16, 2013 By 6 Comments
… that match no rows or insert statements that have duplicate key errors may be faster than an actual database write. The…. All graphs looked like this (we did 39 measurements), the next graph shows chunk 4’s workload warmed up with chunk… graph, each chunk warmed up the buffer pool for the next one. As an additional experiment we tried replaying the same…
Post: Virident vCache vs. FlashCache: Part 2
May 17, 2013 By 3 Comments
…_write_io_threads = 16 We call this configuration B. The next one contained four SSD-specific optimizations based partially on some… these various tests. Clockwise from the top left in the next graph, we have “no cache”, “FlashCache”, “vCache with no time… thread_stack = 192K tmp_table_size = 64M serverid = 101 key_buffer_size = 8M read_buffer_size = 1M read_rnd_buffer…
Post: Repair MySQL 5.6 GTID replication by injecting empty transactions
March 26, 2013 By 1 Comment
… an error: Last_SQL_Error: Error ‘Duplicate entry ’4′ for key ‘PRIMARY” on query. Default database: ‘test’. Query: ‘insert into t… the GTID we want to skip. STOP SLAVE; SET GTID_NEXT=”7d72f9b4-8577-11e2-a3d7-080027635ef5:5″; BEGIN; COMMIT; SET GTID_NEXT=”AUTOMATIC”; START SLAVE; [...] Retrieved_Gtid_Set: 7d72f9b4-8577-11e2-a3d7-…
Post: Keynotes, BOFs, and the Community Networking Reception at Percona Live MySQL Conference and Expo
April 15, 2013 By 1 Comment
The Percona Live MySQL Conference and Expo begins next Monday and runs April 22-25, 2013. Attendees will see … limited number of $5 Expo Only passes. Use discount code “KEY” when registering for the Percona Live MySQL Conference. Hurry, though… the keynotes, BOFs, or Community Networking Reception, use discount code “KEY” for a $5 Expo Only pass. And if you cannot…
Post: Getting MySQL to use full key length
January 31, 2007 By 5 Comments
… table: msg132 type: ref possible_keys: group_id,thread_id,groupid_published,grp_subj key: group_id key_len: 8 ref: const,const… at least for simple ranges. Even if further restrictions by next key part will only barely increase selectivity it anyway does not… select_type: SIMPLE table: msg132 type: range possible_keys: group_id key: group_id key_len: 12 ref: NULL rows: 51 Extra: Using…
Post: To pack or not to pack - MyISAM Key compression
May 13, 2006 By 4 Comments
… uncompressing keys to find matching key value. This means the following will apply: Forward range/index scan will be fast (read_next) as… and will not uncompress block from the start to retrieve next value Reverse range/index scan will be slower (read_prev… NULL default ”, KEY `c` (`c`), KEY `id` (`id`) ) ENGINE=MyISAM Index size: PACK_KEYS=DEFAULT – 1550K PACK_KEYS=1 – 1453K PACK_KEYS=0 – 8176K As…
