OpenIndiana & ZFS

tmpfs的效能可以透過特殊方法提升，要動態提升可以透過command：

# echo 'tmp_nopage/W 1' | mdb -kw

此外可以透過設定檔讓系統開機時自動設定，透過修改/etc/system：

set tmpfs:tmp_nopage=1

原始說明節錄如下：

When a tmpfs file is created or modified, pages are marked dirty. Tmpfs pages stay dirty until the file is deleted. The only time that the tmpfs_putpage() routine pushes the dirty tmpfs pages to the swap device is when the system experiences memory pressure. Systems with no physical swap device or configured with plenty of physical memory can avoid this overhead by setting the tmpfs tunable.

中文意思大概是說，如果你沒有「實體」的裝置來當tmpfs（用硬碟當swap空間），或者你的記憶體超多不怕用不完，你就可以設定這個參數。

Reference: http://tad1982.blogspot.com/2011/05/improving-tmpfs-performance-in-solaris.html