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From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
To: Adam Nowacki <nowakpl@platinum.linux.pl>
Subject: Re: ZFS regimen: scrub, scrub, scrub and scrub again.
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> then stored on a different disk. You could think of it as a regular RAID-5 
> with stripe size of 32768 bytes.
>
> PostgreSQL uses 8192 byte pages that fit evenly both into ZFS record size and 
> column size. Each page access requires only a single disk read. Random i/o 
> performance here should be 5 times that of a single disk.

think about writing 8192 byte pages randomly. and then doing linear search 
over table.

>
> For me the reliability ZFS offers is far more important than pure 
> performance.
Except it is on paper reliability.