June 19, 2013

Post: Choosing a MySQL HA Solution - Post-Webinar Q&A

you run a virtual machine, in most cases your virtual disk is basically nothing more than a filea relay master (it can be on the same machine if you useshould work fine with 5.6 if you‘re not using GTID-based replication. If you are using GTID-based replication, it looks like you

Post: The write cache: Swap insanity tome III

should know) about Linux swappiness setting, which basically controls how important is the file cache for Linux. Basically, with InnoDB, since the fileyou need to interleave the allocation of memory for the MySQL process using the numactl utility, drop the file

Post: Should you have your swap file enabled while running MySQL ?

…arises if you should have swap file enabled or disable it ? I’ve seen production successfully running on boxes both with and without swap file so…really used. These would be first valid candidates to swap out. Second if you have swap file you get a bit more flexibility. What happens if you miscounted…

Post: Aligning IO on a hard disk RAID – the Theory

… that different file systems (and different versions of them) might be using different units for these options so you should refer to a manual on… 9767488+ 83 Linux /dev/sda2 19535040 27342629 3903795 82 Linux swap / Solaris /dev/sda3 27342630 2339835119 1156246245 8e Linux LVM sda1…

Post: Why Swapping is bad for MySQL Performance ?

using more memory for cache and pushing application to the swap. This causes swappingswap file. The bottom line: You should configure system so no swapping activity is going on during normal operations. The swap file itself may be justified – if you

Post: How Percona does a MySQL Performance Audit

… is a dedicated master server). The machine has a lot of swap, but basically none is used. This isn’t all that relevant, as you… the machine swapping actively? (This is more important than whether it’s using swap.) There are a lot of combinations of possible things you can… it in a text file, and explain what I’m seeing to the client. Anything I see that looks wrong should be explained…

Post: How to load large files safely into InnoDB with LOAD DATA INFILE

… starts swapping between its buffer pool and the tablespace on disk. Most seriously, if something should …what you should expect for B-Tree indexes. The two curves on the Cacti graph actually show both files…overall. I also used ‘time’ to run the Perl fifo script, and it used a few minutes of …

Post: Percona XtraDB Cluster - installation and setup webinar follow up Q&A

you recommend a three node cluster for production use? A: Yes, that’s the recommended configuration. The number of nodes/data centers shouldyou migrate to XtradbCluster from a traditional Master Slave scenario when the data set is very large? Can you swap in Binaries ? Afile my.cnf ? A: …

Post: Using MyISAM in production

… errors are discovered etc. You should not think about this … what you would expect from database server and saves you from a lot…you have decent myisam_sort_buffer_size and large myisam_max_sort_fileswapping. Second – table will be locked while repair is going. If this is frequently used table you

Post: Choosing innodb_buffer_pool_size

… it is Dedicated MySQL Server you may not have a good use for that memory anyway. Another thing you should keep into account is Innodb… you may have is making your OS happy and avoiding swapping out MySQL Process or other important processes to make room for file… of percent. Some people try to solve it with disabling swap file but it can hurt another way – OS may kill MySQL…