… disks in the RAID. This turns out to be the same as the size formulas I gave above: RAID 1+0: is a set of mirrored drives, so the number here is num drives / 2. RAID 5: is striped…, so the number here is num drives – 1. In our case, it is RAID 1+0 64k stripe with 8 drives. Since those drives…
Post: Aligning IO on a hard disk RAID – the Theory
June 9, 2011 By 18 Comments
…, 6 or any variation of them (5+0, 1+0, 1+0+0 etc.). While IO inside the RAID is perfectly aligned to disk sectors (again due… more interesting alignment example, let’s assume we have a RAID with 256k stripe element size and a misalignment in partition…- this RAID does not really have 255 heads and 63 sectors per track: db2# fdisk -l Disk /dev/sda: 1198.0 GB…
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 13 Comments
…, Temperature 34C, isSOHGood= VirtualDev Size RAID Level Disks SpnDpth Stripe Status Cache ========== ========= ========== ===== ======= ====== ======= ========= 0(no name) 1.088 TB 1 (1-0-0) 2 2-2 64 Optimal… were run twice – first with RAID controller cache set to Write-Through and then to Write-Back. 1. Baseline – misalignment on the…
Post: Looking for RAID Controller without Battery Learning problems ?
January 5, 2012 By 11 Comments
…/StorMan/arcconf getconfig 1 LD Controllers found: 1 ———————————————————————- Logical device information ———————————————————————- Logical device number 0 Logical device name : RAID10-A RAID level : 10 Status…
Comment: FlashCache: tpcc workload with FusionIO card as cache
June 8, 2010 By 20 Comments
… (usually 4 drives, they tried hardware RAID, software RAID, RAID 1+0 and RAID 0), but in all cases the RAID controller or software couldn’t predict when…
Post: Performance improvements in Percona 5.0.83 and XtraDB
July 14, 2009 By 27 Comments
… PowerEdge R900 with 16 cores and 32GB of RAM and RAID 10 on 8 SAS disks. And again as usually our… used innodb_adaptive_checkpoint in this case for XtarDB / 5.0.83-percona. And, by the way, Yasufumi also made new… performance, let me refresh: – XtraDB is based on InnoDB plugin 1.0.3, with all its benefits like FAST INDEX CREATION, table…
Post: Percona Toolkit 2.1 with New Online Schema Change Tool
April 5, 2012 By 10 Comments
…, it had many limitations and missing features. The new 2.1 version of the tool removes those limitations and makes the… these tools rapidly, for example, to support new types of RAID controllers. Percona Toolkit is a hot topic at the upcoming… Percona Toolkit’s release today, there is also a version 1.0 GA release of the Percona Monitoring Plugins project. It features…
Post: Recovering Linux software RAID, RAID5 Array
August 27, 2011 By 2 Comments
… Time : Fri Aug 26 13:51:11 2011 Raid Level : raid5 Used Dev Size : -1 Raid Devices : 6 Total Devices : 5 Persistence : Superblock…] sdb3[1] sda3[0] 14627723520 blocks super 1.2 level 5, 64k chunk, algorithm 2 [6/5] [UUUUU_] So you can see RAID is….61 TB Current LE 223041 Segments 1 Allocation inherit Read ahead sectors 0 So we have RAID volume back but LVM shows this…
Post: EC2/EBS single and RAID volumes IO benchmark
August 6, 2009 By 14 Comments
… steps: mdadm -v –create /dev/md0 –chunk=256 –level=raid1 –raid-devices=2 /dev/sdj /dev/sdk mdadm -v –create /dev…-threads=$threads –init-rng=on \ –file-num=1 –file-extra-flags=direct –file-fsync-freq=0 run \ >> sysbench-size-$size-mode-$mode… EC2/EBS environment it’s definitely worth to consider some RAID setup. RAID5 does not show benefits comparing with others, and…
Post: Intel 320 SSD read performance
July 29, 2011 By 11 Comments
… SSD strip RAID ratio RAID/Intel 320 ratio RAID/Intel 320 strip 1 0.53 0.56 6.13 11.57 10.95 2 0.72 0.59 7.27 10.10 12.32 4 0.89 0.74 10.07 11.31 13.61 8 1.24 0.95 15.63 12.60 16.45 16 1.76 1.38 25.52 14.50…
