… this case – it is not something MySQL related. I tested things on RHEL5, RAID10 volume with 6 hard drives (BBU disabled) though… any system doing writes to experience the “performance shock” when LVM snapshot is created with greatly reduced capacity which when will… (in particular sequential file reads). If you’ve done some LVM performance tests yourself or will be repeating mine (parameters posted…
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 13 Comments
… over 1TB in size. When I added LVM on top however, I made the logical volume slightly below 1TB. Investigating this I… performance with different IO alignment, not different MySQL configurations, I didn’t try out different MySQL versions or settings. Moreover, I have…-87 with the following my.cnf configuration: [mysqld] datadir=/data/mysql socket=/var/run/mysqld/mysqld.sock innodb_file_per_table…
Post: Is disk Everything for MySQL Performance ?
April 25, 2008 By 7 Comments
… they have instead of how many systems they have” on MySQL UC2008 Scalability Panel ? Indeed disks MAY be the most important… it very easy to use LVM for backups while assuming you have BBU on the raid volume impact on transactional log write… recover to last committed transaction in case your data RAID volume was trashed. Regarding SWAP – I tend to have it but…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
… three commands are for giving me information about LVM devices, volume groups, and logical volumes. At this point, unless I’ve seen something…=/var/db/mysql –user=mysql –pid-file=/var/run/mysqld/mysqld.pid –skip-external-locking –port=3306 –socket=/var/db/mysql/mysql.sock consult…_tables and Created_disk_tmp_tables, I’ll paste in mysql> show global variables like ‘%table_size%’; +———————+———–+ | Variable_name | Value | +———————+———–+ | max…
Post: Faster Point In Time Recovery with LVM2 Snaphots and Binary Logs
February 23, 2012 By 3 Comments
… volume mysql-data-201202230157 started. mysql-data: Merged: 2.3% mysql-data: Merged: 0.2% mysql-data: Merged: 0.0% Merge of snapshot into logical volume mysql… somehow blew up in flames, hardware problems or encounter and LVM bug, your snapshots are useless. Also, you cannot test restore…
Comment: Using LVM for MySQL Backup and Replication Setup
August 18, 2011 By 53 Comments
… to pursue other avenues like lvm snapshot . So i can easily lock the mysql tables and take a lvm snapshot with lvcreate in… seconds and then release the mysql lock . Now that I have the snapshot of the original volume lets say of 1 TB… read only and configure mysql to use it , will that work ? and will that impact on the original volume in any way…
Comment: Disaster: LVM Performance in Snapshot Mode
February 9, 2009 By 55 Comments
… COW technology on various levels – volume manager (LVM, VXVM) or in the filesystem (VxFS). If you use LVM snapshots the choice of the… ~]# lvcreate –size 60g –snapshot –name snap /dev/VolGroup20/mysqldata Logical volume “snap” created 1379.3 | 1104.6 0.1 68.7… be a good representation of what MySQL is doing so we are currently testing xfs with MySQL. But if my speculation are…
Comment: Estimating Undo Space needed for LVM Snapshot
June 11, 2008 By 5 Comments
…: “”" Also I’ve just recently started making a separate logical volume for MySQL binlogs. This helps just for data management (its much…) so we had *plenty* of space. We were also doing LVM snapshots to back up our dbs, but we were using LVM 1, and wrote our own script. IIRC we allowed 10% of a ~2TB volume for snap. Since…
Post: How reliable RAID really is
June 30, 2006 By 13 Comments
…should be interested to many MySQL DBAs and other people involved running MySQL In production. Recently I’ve…could be interesting to try to integrate DRBD with LVM so snapshot could be taken and synchronized …restored in the background back to the local volume. Local Networks are fast these days so it…
Comment: Estimating Undo Space needed for LVM Snapshot
June 10, 2008 By 5 Comments
… to avoid mishaps) for LVM snapshotting. Also I’ve just recently started making a separate logical volume for MySQL binlogs. This helps just… to look for more table storage) but it definitely allows mysql snapshots to be a lot smaller. I have to agree… master status; > status.log show slave status; >> status.log make lvm snapshot of data partition unlock tables; mount snapshot in snapshots…
