Is it a good idea to deploy your database into the cloud? It depends. I have seen it work well many times, and cause trouble at other times. In this blog post I want to examine cloud-based I/O. I/O matters a lot when a) the database’s working set is bigger than the server’s memory, or [...]
MySQL 5.5.8 and Percona Server: being adaptive
December 20, 2010 By 25 Comments
As we can see, MySQL 5.5.8 comes with great improvements and scalability fixes. Adding up all the new features, you have a great release. However, there is one area I want to touch on in this post. At Percona, we consider it important not only to have the best peak performance, but also stable and predictable performance. I refer you [...]
Percona white paper: Forecasting MySQL Scalability
November 16, 2010 By 6 Comments
Ewen and I have just published Percona’s latest white paper, Forecasting MySQL Scalability with the Universal Scalability Law. This is essentially a streamlined walk-through of Dr. Neil J. Gunther’s book Guerrilla Capacity Planning, with examples to show how you can apply it to MySQL servers. One thing alluded to in the paper is extracting the [...]
RAID throughput on FusionIO
March 24, 2010 By 7 Comments
Along with maximal possible fsync/sec it is interesting how different software RAID modes affects throughput on FusionIO cards. In short conclusion, RAID10 modes really disappoint me, the detailed numbers to follow. To get numbers I run
1 | sysbench fileio |
test with 16KB page size, random read and writes, 1 and 16 threads, O_DIRECT mode. FusionIO cards are [...]
Why you should ignore MySQL’s key cache hit ratio
February 28, 2010 By 28 Comments
I have not caused a fist fight in a while, so it’s time to take off the gloves. I claim that somewhere around of 99% of advice about tuning MySQL’s key cache hit ratio is wrong, even when you hear it from experts. There are two major problems with the key buffer hit ratio, and [...]
FusionIO – time for benchmarks
December 8, 2009 By 10 Comments
I posted about FusionIO couple times RAID vs SSD vs FusionIO and Testing FusionIO: strict_sync is too strict…. The problem was that FusionIO did not provide durability or results were too bad in strict mode, so I lost interest FusionIO for couple month. But I should express respect to FusionIO team, they did not ignore [...]
NILFS – may be not yet
August 8, 2009 By 5 Comments
Inspired by NILFS: A File System to Make SSDs Scream and some customers asked if they should try NILFS on their SSD disks I decided to run quick tests to see how it performs. Installation on our Ubuntu 8.10 with SSD disk (Intel X25-E, 32GB) was pretty plain and I got partition with NILFS without [...]
Dissection of EC2 / EBS volume
August 7, 2009 By 4 Comments
So during preparation of XtraDB template for EC2 I wanted to understand what IO characteristics we can expect from EBS volume ( I am speaking about single volume, not RAID as in my previous post). Yasufumi did some benchmarks and pointed me on interesting behavior, there seems several level of caching on EBS volume.
RAID vs SSD vs FusionIO
May 1, 2009 By 17 Comments
In benchmarks passion (see my two previous posts) I managed to setup all three devices (RAID was on board; Intel X25-E SSD connected to HighPoint controller, FusionIO card) on our working horse Dell PowerEdge R900 (btw, to do that I had to switch from CentOS 5.2 to Ubuntu 8.10, as CentOS was not able to [...]
Fix of InnoDB/XtraDB scalability of rollback segment
January 18, 2009 By 9 Comments
Recently I wrote about InnoDB scalability on 24-core box, and we made research of scalability problems in sysbench write workload (benchmark emulates intensive insert/delete queries). By our results the problem is in concurrency on rollback segment, which by default is single and all transactions are serialized accessing to segment. Fortunately InnoDB internally has mechanism to [...]
