…workload. So benchmark to be sure. In Innodb besides scalability changes in later …performance enhancement requests. It takes time for the patches to mature. We improved the …to a mechanical disk. I do not know how it is for sequential writes, like log flushes. A question is why to use a flash memory…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…how to build for massive scalability, how to do read-write splitting without breaking the user experience, how to…to know ahead of time so we don’t spend time on things you have no way to change…to allocate a lot of memory to mysqld. Next I look at a couple of all-in-one commands. For…flush…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…time. Also number of pending fsync operations is displayed. For writes Innodb has to ensure data makes it to the disk – just passing it to…changes up to which has been flushed from buffer pool. Changes having higher log sequences may still only be recored in logs and not flushed…
Post: Choosing innodb_buffer_pool_size
November 3, 2007 By 38 Comments
…to leave space for other MySQL needs while factoring this in. The next step would be to decide How Much Memory do you need for…to do anything. On Linux, FreeBSD, Solaris you need to set innodb_flush…to be less eager to swap things by echo 0 > /proc/sys/vm/swappiness is another helpful change…
Post: Disaster: MySQL 5.5 Flushing
September 18, 2011 By 27 Comments
…How to diagnose it? This is question I am asked, how do we know that stall we see is related to InnoDB flushing…for SSD in Percona Server we have “innodb_adaptive_flushing_method = keep_average”. Unfortunately on spinning disks…memory is better), the same way InnoDB will not be able to change…
Post: What to tune in MySQL Server after installation
September 29, 2006 By 116 Comments
…for most common workload. After you get these settings right other changes…time – it is not rare to see key_buffer being set to…flush log to the disk but only flush it to OS cache. The log is still flushed to the disk…to increase sort_buffer_size even if you have 64GB of memory to…
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 11 Comments
…Memory, BBU Present BBU | 100% Charged, Temperature 34C, isSOHGood= VirtualDev Size RAID Level Disks…for a customer so I just used the setting that they would have used anyway. One thing I did change…to IO alignment yourself. In this case offset is correct, but file system is unaware how to…
Post: When is it a time to upgrade memory ?
September 16, 2008 By 11 Comments
… busy sooner or later. How to figure out if it is time for upgrade when ? Look … dramatically or may be because queries changed their plans. Do the sizing This …flush_method=O_DIRECT) and see how performance depends on buffer size so you get and understanding what Memory-To-Disk ratio is optimal for…
Post: Falcon Storage Engine Design Review
January 12, 2007 By 19 Comments
…flushes on commit, plus ether you use XA to synchronize these which is expensive or it will be possible for your transaction changes to…memory to hold all transaction changes. I agree most transactions are small and should be fine but if you have long running transactions, for…
Post: InnoDB Flushing: a lot of memory and slow disk
March 31, 2011 By 57 Comments
…for a long time (minutes). This comes from the fact that MySQL performs changes in memory at a faster rate than it can write to disks…flushing to disk is not able to keep up with changes in memory, we need to have a throttling mechanism that will limit the rate of changes in memory…
