… Unix at a time. On Windows, InnoDB uses native async I/O, and can perform many read-aheads at the same time… see the full write speed of the disk for throughput. INNODB uses fuzzy checkpointing to commit data to disk. The problem that weâ…% of the raw disk write speed. Since the commit isn’t perfectly serial it’s having to seek on disk which slows down…
Comment: Using netcat to copy MySQL Database
June 1, 2009 By 25 Comments
… change the speed in the middle of transfer in case of the machine’s disk I/O is hot. You can limit disk transfer at any moment during copy process using simple throttle tool. Just put it between pipes like this (I suggest…|bar|nc $destination_host $tcp_port and to limit the speed to for example to 20Mbit: throttle -t /tmp/throttle.ctl…
Post: MySQL performance on EC2/EBS versus RDS
August 4, 2011 By 11 Comments
… the number and speed of CPU cores you can get, and I/O performance can be highly variable. You can mask I/O problems on… do, the limitations on the core counts and effective CPU speeds can be a bottleneck. My experience and intuition are that… as compared to directly attached disks or SSD devices. InnoDB doesn’t handle this very well, because I/O tends to be a…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
… are, both in terms of size and spindle speed. I need to know how many physical spindles are … values for Created_tmp_tables and Created_disk_tmp_tables, I‘ll paste in mysql> show global variables like… know a lot about the I/O subsystem. And by now I know that I should concentrate in certain areas –…
Post: Recovery deleted ibdata1
August 10, 2012 By 9 Comments
…until all dirty pages are flushed on disk. For that we will monitor checkpoint age…at 363096003 Max checkpoint age 7782360 To speed up flushing we can set dirty …I/O ——– I/O thread 0 state: waiting for i/o request (insert buffer thread) I/O thread 1 state: waiting for i/o request (log thread) I/O…
Comment: Tokyo Tyrant - The Extras Part I : Is it Durable?
August 20, 2010 By 5 Comments
… end of the data tables or tranlog). Also tuning your I/O buffers & cache to actually be *smaller* might help, avoiding the… disk heads against a big writer. Although RAID10 brings 2x (or 3x) overhead in terms of disk usage, if it’s reliability & speed you want then hardware to the rescue…. As for speed, the type of…
Comment: Benchmarks of new innodb_flush_neighbor_pages
July 3, 2012 By 8 Comments
….6.html These improvements sound interesting to page flush and i/o problems? Explicit Partition Selection, Split Kernel Mutex, Multi-Threaded Purge… to disk not ram for mysql like varnish for http webserver should speed up mysql since its already technically on the disk. Also btw does anyone know when percona 5.6 is going to be released or if I should switch…
Post: How to load large files safely into InnoDB with LOAD DATA INFILE
July 3, 2008 By 29 Comments
… between its buffer pool and the tablespace on disk. Most seriously, if something should happen and the…speed up the load? Not appreciably. There actually was a tiny speedup, but it’s statistically insignificant IMO. I… rows and that’s why it causes less I/O overall. I also used ‘time’ to run the Perl…
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 13 Comments
…Speed Form Factor Type Type Detail ========= ======== ================= ============= ============= =========== DIMM_A1 4096 MB 1333 MHz (0.8 ns) DIMM {OUT OF SPEC} Other … # Disk…, not different MySQL configurations, I didn’t try out … = 2 innodb_flush_method = O_DIRECT innodb_log_buffer_size…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…I/O ——– I/O thread 0 state: waiting for i/o request (insert buffer thread) I/O thread 1 state: waiting for i/o request (log thread) I/O… to ensure data makes it to the disk – just passing it to OS cache is … index Innodb builds for some pages to speed up row lookup replacing btree search with …
