… to know how all these settings work together it can be tricky knowing how the specific change will affect overall memory usage. This… kill mysqld… So I’d like a way of seeing how much memory the different settings will use on the box and if… my.cnf or SHOW GLOBAL VARIABLES) and just tells you how much memory will be allocated for those settings.
Post: MySQL performance on EC2/EBS versus RDS
August 4, 2011 By 11 Comments
… buffer pool, which means you need it to fit in memory. The largest instances currently have a bit less than 70GB… the inserts go into one partition, whose indexes fit in memory. The more elaborate you get with this — such as putting… think about. The physical and logical database design influences greatly how much memory and disk resources are required. The application’s access patterns…
Post: The tool I've been waiting for years
March 18, 2008 By 10 Comments
… cached. You can also use it with Innodb to see how much memory are you wasting with double buffering by not using of… own cache memory – Innodb, Falcon, Maria. Having information about how large portion of table is cached would allow optimizer to take much smarter… pattern to the file you can draw some conclusions about how much IO pressure we have on this server. P.S If…
Post: How expensive is USER_STATISTICS?
June 2, 2012 By 14 Comments
… how expensive it is. There are two dimensions to the question. One is how much slower the server becomes, and the other is how much more memory it uses. The second question… the gperf heap profiler and /proc/pmap to help examine memory usage. The results? After running the benchmark on 25,000…
Post: Predicting how long data load would take
May 24, 2007 By 14 Comments
… cause much longer downtime than planned. Hardware Configuration If you need to load data quick do it on decent hardware. Especially memory… 3600; du -sh” in the database data directory to see how much data is loaded per hour (assuming your Innodb tablespace did… 15GB in size (allowing to fit all BTREE indexes in memory) plus we loaded data in parallel and our rows were…
Post: When is it a time to upgrade memory ?
September 16, 2008 By 11 Comments
…=O_DIRECT) and see how performance depends on buffer size so you get and understanding what Memory-To-Disk ratio is optimal…_size you can use it as guidance to add more memory or more servers. Of course this is all oversimplifications – you… CPU scalability in particular if you have many cores, consider how much IO bandwidth you have etc but these factors already should…
Post: InnoDB memory allocation, ulimit, and OpenSUSE
August 23, 2010 By 7 Comments
… requested allocations I added a debugging fprintf() to tell me how much was being allocated and whether it was successful. I discovered…. Apparenly OpenSUSE defaults are set in proportion to physical memory to keep the memory-hungry applications from taking the system down. On… physical memory, 2 GB swap it decided to set the virtual memory ulimit (-v) to 77.27 GB, and the physical memory (-m…
Comment: Choosing innodb_buffer_pool_size
April 15, 2010 By 39 Comments
…-10 G (probably closer to 8, and then monitor system memory usage before raising more, because I’m careful like that… as well. You must leave at least 10% of your memory for your system to run smoothly, especially with that small… have to do the math to see how many connections you have at once and how much memory each connection takes up…I’m…
Post: How expensive is a WHERE clause in MySQL?
October 31, 2008 By 17 Comments
… I’ve been wanting to test for some time. How much overhead does a trivial WHERE clause add to a MySQL… enough to test, but small enough to fit wholly in memory: CREATE TABLE `t` ( `a` date NOT NULL ) ENGINE=InnoDB DEFAULT… clauses, but I’m not really interested enough to spend much time on it. I just wondered whether the WHERE clause…
Comment: Falcon Storage Engine Design Review
January 12, 2007 By 19 Comments
… also a great deal cheaper to reference a record in memory than in the page cache. The record cache also holds… a fixed asset, such as memory. There configuration management makes sense because the user probably knows how much memory can be allocated to Falcon… index. Clustered indexes are a vestige from the small, expensive memory past. No “using indexâ€. First, the record cache greatly…
