Changes between Version 22 and Version 23 of FAQ/GFS


Ignore:
Timestamp:
05/26/11 04:16:10 (3 years ago)
Author:
digimer
Comment:

Moved Bob's two READMEs to wiki pages.

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  • FAQ/GFS

    v22 v23  
    352352gfs_tool settune <mount point> statfs_fast 1 
    353353}}} 
    354 The "fast statfs" feature has limitations.  First, it's not persistent.  You have to turn the feature on each time you reboot.  Many people add gfs_tool commands (as above) to their "gfs" init script (/etc/init.d/gfs) so they don't have to remember to turn it on every time they reboot.  Second, you need to have all the nodes in your cluster agree: they should all be using fast statfs, or else none of them should be using it.  If some do and some don't, it will be unpredictable.  Third, it has been known to lose its place.  For example, if you use "gfs_grow" to extend your GFS file system, the fast statfs feature will not be informed of the new file system size.  For normal, day-to-day file system operations, this is not a problem.  (This is also not a problem for GFS2). For more information on GFS's "fast statfs" please see: http://people.redhat.com/rpeterso/Patches/GFS/readme.gfs_fast_statfs.R4 
     354The "fast statfs" feature has limitations.  First, it's not persistent.  You have to turn the feature on each time you reboot.  Many people add gfs_tool commands (as above) to their "gfs" init script (/etc/init.d/gfs) so they don't have to remember to turn it on every time they reboot.  Second, you need to have all the nodes in your cluster agree: they should all be using fast statfs, or else none of them should be using it.  If some do and some don't, it will be unpredictable.  Third, it has been known to lose its place.  For example, if you use "gfs_grow" to extend your GFS file system, the fast statfs feature will not be informed of the new file system size.  For normal, day-to-day file system operations, this is not a problem.  (This is also not a problem for GFS2). For more information on GFS's "fast statfs" please see: [wiki:readme.gfs_fast_statfs.R4 readme.gfs_fast_statfs.R4] 
    355355 
    356356 * Use -r 2048 on gfs_mkfs and mkfs.gfs2 for large file systems. 
     
    429429For more information on glock trimming, please see: 
    430430 
    431 http://people.redhat.com/rpeterso/Patches/GFS/readme.gfs_glock_trimming.R4 
     431[wiki:readme.gfs_glock_trimming.R4 readme.gfs_glock_trimming.R4] 
    432432 
    433433Other GFS performance considerations: