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System : Centos 6.4, PerconaDb/MySQL 5.5.31

Im running relatively small mysql database with some 30 databases, total amount of 12Gb, but heavy on reads, updates and writes (texts, posts, user data and user actions are being CRUD evenly during the day). Its a typical relational db, no data warehouse or so.

Currently, its running on some two HDD array (not sure about specs, its hosted) giving the disks quite tough time, with 25% IO utilization, avg 700 IOPS, 5Mbps (according to Newrelic monitoring agent on the server). The whole MySQL server is doing some 540 queries per second, average.

Im considering putting it on separate disk array, and Im considering use SSD for it. Either classic SSD disks, or SSD PCI card.

As there are technical limits of how much data can be written to SSD, before the chips wear out, I'd like to calculate / estimate the amount of time the disks will be good before need to be replaced.

My questions are :

  1. Is it premature optimization ? I cannot rewrite all apps using all the databases, all are indexed as well as possible, I'm no newbie in this, but I accept there might be things to consider and change.
  2. How can I measure the amount of data written by MySQL ? to estimate how long it will probably live on the SSD. Does it even apply on this amount of data, should I care about it at all ?
  3. Do you have any experience with running MySQL on SSD, any best practice to share in here ?
  • I think we need more detail on the hardware options available to you. Any of the SSD approaches will benefit you, but there's a vast difference between a disk form-factor SSD and a PCIe. What type of server hardware is this? – ewwhite Jan 27 '14 at 14:57
  • Thank you for your answer. Currently we are using Fujitsu Primergy RX300 server, no detailed info on this (i have a reason to believe there is no special hw raid card except the one "builtin"). The future server should be custom made by server focused company, based on dual Intel E5-2620v2 CPUs on Supermicro X9DRi-F mobo, but this very customisable, any component can be added as needed. For PCI I'm considering using the OCZ RevoDrive 3, 120Gb or so. For standard SSD disk, Intel or Samsung. – Radek Jan 27 '14 at 15:30
  • Answering the second question - you can use 'iotop' to measure total amount of data written to disk by mysql process. – Andrey Sapegin Feb 2 '14 at 19:20

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