… stripe the LV when we need to and align the partition correctly. We got decent tpcc performance, nearly 37k NoTPM using… gave all those drives to ZFS (30 mirrors + spares + OS partition mirror) and I limited the ARC size to 4GB. I… from the other drive in the mirror. Better availability and disk usage On purpose, I allocated mirror pairs using drives from…
Comment: MySQL Partitioning - can save you or kill you
April 30, 2013 By 45 Comments
… 20 partitions; they are PARTITION BY RANGE (to_days(…)). However, the ranges are uneven — older partitions cover larger timespans. The last few partitions are… similar in speed between PARTITIONed or non-PARTITIONed. When PARTITIONed, first it has to find and open the required partition, then it drills down… each partition would be about 4 levels. A “point query” in a billion-row (non-partitioned) table will, at worst, hit the disk…
Post: MySQL 5.6 Compatible Percona XtraBackup 2.0.6 Released
March 20, 2013 By 2 Comments
… backup prepare operation. This led to a large increase in disk usage in cases when there are many small InnoDB tablespaces… for the bug #711166 introduced a regression that caused individual partition backups to fail when used with –include option in innobackupex…
Post: Aligning IO on a hard disk RAID – the Theory
June 9, 2011 By 18 Comments
… RAID with 256k stripe element size and a misalignment in partition table – partition /dev/sdb1 starts 11 sectors ahead of the stripe… Model: LSI MegaRAID 8704EM2 (scsi) Disk /dev/sda: 2339840000s Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size… this is not a system boot disk you are working on, you may not need partition table at all – you can just…
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 13 Comments
… MHz (0.8 ns) DIMM {OUT OF SPEC} Other … # Disk Schedulers And Queue Size ############################# sda | [deadline] 128 # RAID Controller ############################################ … – for XFS file system on a raw partition I was using full partition size which was slightly over 1TB in …
Post: Filling the tmp partition with persistent connections
August 6, 2012 By 14 Comments
… /tmp partition is a common trick to improve the performance of on-disk temporary tables. Servers usually have less RAM than disk space so those kind of partitions are very limited… runs out of disk space on /tmp/partition. The first step is clear, check which files are on that partition: # ls -lah /tmp…
Comment: MySQL Partitioning - can save you or kill you
June 28, 2012 By 45 Comments
… for the analysis.. Have created a test table with the partitions@ described. Also, modified indexes –> 1 index (ObjectClass, Timestamp), PK –> (ObjectClass… ). This base mysql version (5.1.56) supports partitions, but does not support partition pruning. 3. The records in the production (as…) should be in chronological order of timestamp. 4. The underlying disk partition is DRBD, with replication to a second standby server for…
Post: Is disk Everything for MySQL Performance ?
April 25, 2008 By 7 Comments
… many systems they have” on MySQL UC2008 Scalability Panel ? Indeed disks MAY be the most important part in your system performance… always the case. There are whole classes of systems where Disk performance is not that important – consider for example systems where… files (and whole datadir) and log files on the same partition as well because this makes it very easy to use…
Comment: Star Schema Bechmark: InfoBright, InfiniDB and LucidDB
January 10, 2010 By 48 Comments
… tmp disk partition ? I fairly can’t recall any servers setup that has 64-128GB of RAM with 128-256GB of SWAP partition…
Comment: Aligning IO on a hard disk RAID – the Theory
June 9, 2011 By 18 Comments
Thanks for the great article! Especially the part about disk partition tables. Regarding RAID stripe size: during DBA classes in August, …? Most people seem to run default stripe sizes provided by disk controllers they use. Thank you.
