Difference between revisions of "Veritas vxfs filesystem performance"

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  Unable to open file in DIRECTIO_ON mode, error: (25) Inappropriate ioctl for device
 
  Unable to open file in DIRECTIO_ON mode, error: (25) Inappropriate ioctl for device
  
To get the best performance I ran some tests with different mount options.
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To get the best performance out of this type of filesystem I ran some tests with different mount options.
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A normal mount has these options set: read/write/nosuid/delaylog/largefiles/ioerror=mwdisable
 
A normal mount has these options set: read/write/nosuid/delaylog/largefiles/ioerror=mwdisable
 
Additional mount options used in the test were: mincache=direct and convosync=direct
 
Additional mount options used in the test were: mincache=direct and convosync=direct
  
See below graphs for a quick overview of the resulting throughput.
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See below graphs for a quick overview of the resulting throughput. For each bar the specific Sybase device settings are given (dsync / directio), as well as the Vertitas mount options. A higher bar means better throughput.
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[[Image:Read_vxfs.jpg]]
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[[Image:Example.jpg]]
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[[Image:Write_vxfs.jpg]]
  
Note: the graphs will be posted April 28, 2007.
 
  
 
[[Category:ASE]]
 
[[Category:ASE]]

Latest revision as of 12:31, 29 April 2007

In an attempt to use the direct I/O feature of Sybase ASE 15 on a Veritas filesystem I ran into a couple of issues. It seems that direct i/o is not possible on this type of filesystem. You will see this in the errorlog:

Unable to open file in DIRECTIO_ON mode, error: (25) Inappropriate ioctl for device

To get the best performance out of this type of filesystem I ran some tests with different mount options.

A normal mount has these options set: read/write/nosuid/delaylog/largefiles/ioerror=mwdisable Additional mount options used in the test were: mincache=direct and convosync=direct

See below graphs for a quick overview of the resulting throughput. For each bar the specific Sybase device settings are given (dsync / directio), as well as the Vertitas mount options. A higher bar means better throughput.


Read vxfs.jpg


Write vxfs.jpg