HP StorageWorks Scalable File Share - Manual (Page 344)

File system configuration examples C–2
C.1 EVA4000 storage examples
Example C-1 shows a file system that is not optimally configured. The example is taken from a system where
EVA4000 storage is used. The configuration has the following problems:
• There is an uneven number of OST services (5); this will lead to unbalanced OST serving.
• One of the OST LUNs is very small (
ost8
is only 2GB). Again, this will result in an imbalance in OST
serving. HP recommends that all of the OST services in a file system are the same size.
• Some of the OST LUNs are marginally smaller than others.
• The OST LUNs were not specified to the
create filesystem
command in the optimal order. As
explained in Section 5.1.4.1, the order in which the OST services are specified to the
create
filesystem
command determines the adjacency of the OST services in the LOV and thus affects file
system performance. LUNs that are on the same controller pair are served from the same server and
should be adjacent in the LOV. This is not the case in this example.
Example C-1 EVA4000 file system example — incorrect configuration
sfs> show filesystem gm_south
Name: gm_south
OSTs: ost[3-7]
State: stopped
Mountpoint: /mnt/gm_south/
Stripe size: 4194304
Stripe count: 4
Interconnect: elan gm tcp
MDS mount options: acl,user_xattr
OST mount options: extents
Lustre timeout: 200
Quota options: quotaon=ug
MDS Information:
Name LUN Array Controller Files Used Service State Running on
----- --- ----- ---------- -------- ---- ------------- ----------
mds2 5 1 a 123M 0% stopped south28*
OST Information:
Name LUN Array Controller Size(GB) Used Service State Running on
----- --- ----- ---------- -------- ---- ------------- ----------
ost4 9 2 a 540 5% stopped south29*
ost5 11 3 a 555 5% stopped south30*
ost6 10 2 b 540 5% stopped south30*
ost7 14 3 b 555 5% stopped south29*
ost8 13 3 b 2 9% running south29*
(servers marked * are preferred server; service is not running)
sfs>
Example C-2 shows a better configuration for the same file system.
Example C-2 EVA4000 file system example — good configuration
sfs> show filesystem gm_south
Name: gm_south
OSTs: ost[3-7]
State: stopped
Mountpoint: /mnt/gm_south/
Stripe size: 4194304
Stripe count: 4