RAID 1 (Mirroring and Duplexing) Comparing mirroring and duplexing Mirroring is the simplest method of avoiding data loss when a single disk fails. During writes, data is sent to both disks. During reads, different data can be read from both disks, which provides good read Performance. Duplexing is another form of keeping a copy of data. Where mirroring uses a single controller, duplexing can also handle a controller failure. Duplexing requires an operating system that supports RAID 1.
This site says cost of tiling per square metre is between $95 and $170 psm for floor tiles and $90 and $160 for wall tiles. Those prices include tiles so take $30 psm off those.
1 The per metre rate for laying ceramic tiles can vary between $90 and $150 or even more. 2  Quarry tiles also start at around $90 per square metre, but top out at about $125. 3  Vinyl tiles are the easiest and quickest to lay.4  Expect quotes between $40 and $100 per square metre. The per metre rate for laying ceramic tiles can vary between $90 and $150 or even more. 2  Quarry tiles also start at around $90 per square metre, but top out at about $125. 3  Vinyl tiles are the easiest and quickest to lay.