… to keep it compressed. Unfortunately MySQL does not provide compressed BLOB/TEXT columns (I would really love to have COMPRESSED attribute… you with true data size and performance gains, especially for Innodb tables. With Innodb tables BLOB gets its own page (allocated outside… over 5 times and performance gains were even better because much fewer rows required external storage now. The BLOB/TEXT column compression…
Post: Innodb Performance Optimization Basics
November 1, 2007 By 75 Comments
… of Hardware OS And Application optimization. I call this Innodb Performance Optimization Basics so these are general guidelines which work well… and good performance innodb_log_buffer_size=4M 4M is good for most cases unless you’re piping large blobs to Innodb… default as transaction-isolation=READ-COMMITTED. This option has some performance benefits, especially in locking in 5.0 and even more…
Post: How number of columns affects performance ?
September 28, 2009 By 12 Comments
… place when internal data structures are populated (everything but TEXTs/BLOBs is fixed length when it is being processed). This conversion…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
… area of optimization. I frequently see batch jobs killing server performance overtaking buffer pool. Though full table scan is only one… 8100 bytes InnoDB will not allocate additional space for blobs, even if each blob is larger than 768. 2. InnoDB will allocate…(thread_concurrency, srv_thread_concurrency, PLUGIN_VAR_RQCMDARG, “Helps in performance tuning in heavily concurrent environments. Sets the max\ imum number…
Comment: Falcon Storage Engine Design Review
January 12, 2007 By 19 Comments
… LRU would require a lock, which is unthinkable from a performance perspective. So Falcon keeps a cheap (but, alas, inaccurate) tally… phase index retrievals is one you identified in your performance study – bad performance in the “limit†case, particularly on indexes…€™t materialize blobs unless the blob is referenced and doesn’t rewrite blobs during an update unless the blob itself has changed. Blobs are also…
Post: Dynamic row format for MEMORY tables
September 6, 2011 By 5 Comments
…-length format, either wasting space (VARCHAR) or outright impossible (BLOB). Indexes on BLOB columns are not supported. While we do not consider… are not exhaustive and, of course, if you have a performance-critical application depending on MEMORY tables, they are no replacement…-specific tests. We start by checking if there is any performance regression when the variable-length records are not used, i…
Post: Falcon Storage Engine Design Review
January 12, 2007 By 19 Comments
… I do, and this can be only checked by comparing performance with your own optimized settings and one database engine would… are great. Huge indexes is where large portion of Innodb performance problems come however. We should however see how “compact” they… often. [+] Blob handling optimizations Jim loves BLOBs as his own child, so Falcon is optimized in Blob handling for example having direct blob writes…
Post: What exactly is read_rnd_buffer_size
July 24, 2007 By 4 Comments
… use many queries with ORDER BY, upping this can improve performance” which is cool but it does not really tell you…. Here is how it works: As sort is performed it can be performed having only row pointers together with key value – which… length can be converted to fixed size (basically everything but BLOB/TEXT) MySQL can use read_rnd_buffer to optimize data…
Post: Innodb undo segment size and transaction isolation
January 12, 2011 By 3 Comments
… of “garbage” accumulated in undo segment size which can cause performance degradation as well as increased disk space usage. Long transactions… lot of waste even with small history size if transactions performed large amount of changes. There is something else you need… undo space and it will contain correct pointer to appropriate blob version. Now lets move on to the main topic – how…
Comment: When should you store serialized objects in the database?
January 22, 2010 By 47 Comments
… able to create columns as easy as it does serialized blobs. YMMV, but I’m a little worried that with ‘Broken… a completely different kettle of fish. They don’t want performance, they want it to run anywhere. There’s lots of… of a tablescan and whatever I update. For the E-Blob users that’s a script that pulls everything out, examines…
