… over multiple ports, and with a two-NIC bonded pair you’ll get roughly 1.67x the throughput of a single port… can actually result in performance that’s worse than a single NIC.] The other two NIC ports should be bonded with… and PRM simply attempt to connect and run a simple query, but it’s always possible to build something more involved…
Post: Why MySQL Performance at Low Concurrency is Important
March 27, 2013 By 8 Comments
… the best response times (MySQL server does not use multiple threads to execute query in parallel at this point). Response times at… happen — many batch jobs are written to be single-threaded. MySQL replication is single-thread too, and MySQL 5.6 brings some… database maintenance operations such as “alter table” are run in single-thread too. In fact, chances are your system actually runs…
Post: How multiple disks can benefit for single client workload ?
April 26, 2008 By 4 Comments
… original article I mentioned having multiple hard drives does not help if you have single query (or stream of queries) which you need to… can result in multiple outstanding requests to the disk. Though this does not help dramatically for many “random” update queries. After pages… – single client work load does not necessary means single outstanding disk IO request at all times. So natively it can benefit from multiple…
Post: Shard-Query turbo charges Infobright community edition (ICE)
May 6, 2011 By 23 Comments
… multiple files (for each shard, for later loading) or it can load files directly, in parallel, to multiple hosts. Shard-Query will execute queries… will be described in another post. Complex queries Shard-Query was tested with the simple single table version of this data set in… your data over multiple machines, scaling out to improve query response times significantly. These queries are a great test of Shard-Query features. It…
Post: Cache Performance Comparison
August 9, 2006 By 74 Comments
… on different level (ie single object constructed from multiple query results) MySQL Query Cache may improve performance of your application. Multiple layers of caching may do well Same as CPUs have multiple…
Post: Multiple column index vs multiple indexes
August 22, 2008 By 13 Comments
… on Multiple Indexes vs Two Column Index efficiency. I mentioned in most cases when query can use both of the ways using multiple… however as it is currently implemented so they would use single index range scan. The 2 indexes however benefits to Q3… difference large BETWEEN can make. Conclusion: For benchmarked queries we can see Multiple Column index beats Index Merge in all cases when…
Post: Using Multiple Key Caches for MyISAM Scalability
November 26, 2008 By 8 Comments
… use multiple Key Caches to reduce or virtually eliminate key cache contention. Too bad you can only map single table to single key cache – it would be so much more helpful if you could use multiple key caches… min 23.67 sec) A bit more query hacking and we get a query which will return statements to initialize key buffers…
Post: Fighting MySQL Replication Lag
September 22, 2008 By 7 Comments
… remember is MySQL Replication is single threaded, which means if you have any long running write query it clogs replication stream and… running updates. Queries or transactions containing multiple update queries which add up to long time. I would keep the maximum query length at about… per batch in multiple row insert statement or Fetching data you’re planning to update/delete and having multiple queries to delete it…
Post: Why MySQL could be slow with large tables ?
June 9, 2006 By 141 Comments
… 100 rows/sec. Note multiple drives do not really help a lot as we’re speaking about single thread/query here. So difference…. In MySQL single query runs as single thread (with exeption of MySQL Cluster) and MySQL issues IO requests one by one for query execution, which means if single query…
Post: Distributed Set Processing with Shard-Query
May 14, 2011 By 27 Comments
… to views that are based on only a single base table. Knowing this, the query result set is treated as a materialized… the results back together again. This set logic allows to multiple levels of reduction of the set, all in parallel. All…% of the work, due to the multiple levels of result set reduction. Finally, Shard-Query can automatically partition sets into subsets using…
