quick vfs tuning
korvus at comcast.net
Mon Apr 27 16:42:26 UTC 2009
> The author suggested that increasing the default value of 8 to 16
> resulted in increased read speed, and that increasing it further
> resulted in no noticeable performance gain.
Personally, I've seen changes in vfs.read_max to provide anywhere from a
50-100% improvement in disk read performance. As you have also found,
the "sweet spot" is sometimes higher than 16. I've seen significant
benefits up to vfs.read_max=128 on *some* disk controllers. It really
seems dependent on the disks/controllers, but setting 16 has always
shown a significant improvement over the default 8 for me.
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