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Restoring the default segment preference, Tuning allocation policy settings, Listing allocation policies – HP StoreAll Storage User Manual

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/bin/ibrix_fs_tune -f FSNAME {-h HOSTLIST|-g GROUPLIST}
-S {SEGNUMLIST|ALL|LOCAL}

Restoring the default segment preference

The default is for all file system segments to be preferred. Use the following command to restore
the default value:

/bin/ibrix_fs_tune -f FSNAME {-h HOSTLIST|-g GROUPLIST} -S ALL

Tuning allocation policy settings

To optimize system performance, you can globally change the following allocation policy settings
for a file system:

File allocation policy (see

“File allocation policies” (page 116)

for a list of available policies).

Starting segment number for applying changes.

Preallocation: Number of KB to preallocate for files. The default is a preallocated file size of
256 KB.

Readahead: Number of KB in a file to pre-fetch. The default is 128 KB.

NFS readahead: Number of KB in a file to pre-fetch on NFS systems. The default is 128 KB.

NOTE:

Before tuning allocation policy settings, contact HP Support for guidance on selecting the

best values for your installation.

Use the following command to restore the default file allocation policy:

/bin/ibrix_fs_tune -f FSNAME {-h HOSTLIST|-g GROUPLIST} -p -U

Listing allocation policies

Use the following command to list the preferred segments (the -S option) or the allocation policy
(the -P option) for the specified hosts, hostgroups, or file system.

/bin/ibrix_fs_tune -l [-S] [-P] [-h HOSTLIST | —g GROUPLIST] [-f FSNAME]

HOSTNAME FSNAME POLICY STARTSEG DIRPOLICY DIRSEG
SEGBITS READAHEAD PREALLOC HWM SWM
mak01.hp.com ifs1 RANDOM 0 NONE 0
DEFAULT DEFAULT DEFAULT DEFAULT DEFAULT

Tuning allocation policy settings

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