thanks in advance.
-Brady
On 9/7/10 5:45 PM, "Brady Chang" <bchang@xxxxxxxxxxxxx> wrote:
Hello All,
I have an issue with fragmentation on a particular device
thanks for any advice.
-Brady
I have a Dell r510 with 12 disks
2xraid 5 (6 disks each)
raid group1:
48 GB carved out for os mounted as /
remaining space 2.7 TB for xfs mounted as /data1
raid group2:
48 GB for swap
remaining space 2.7 TB for xfs mounted as /data2
The strange thing is that /data1 never gets fragmented where as /data2 is badly fragmented.
I believe increase allocsize would help, but not sure how to explain why /data2(/dev/sdd) always gets fragmented and not /data1(/dev/sdb)
It's a data warehouse application. the I/O is balanced between /data1 and /data2:
output of xfs_db
[root@sdw4 data1]# xfs_db -c frag -r /dev/sdb
actual 14353, ideal 13702, fragmentation factor 4.54%
[root@sdw4 data1]# xfs_db -c frag -r /dev/sdd
actual 408674, ideal 13719, fragmentation factor 96.64%
df output
/dev/sdb 2.7T 967G 1.8T 36% /data1
/dev/sdd 2.7T 1.1T 1.7T 39% /data2
LABEL=/data1 /data1 xfs allocsize=1048576,logbufs=8,noatime,nodiratime 0 0
LABEL=/data2 /data2 xfs allocsize=1048576,logbufs=8,noatime,nodiratime 0 0
raid config output:
[root@sdw4 data1]# omreport storage vdisk
List of Virtual Disks in the System
Controller PERC H700 Integrated (Slot 4)
ID : 0
Status : Ok
Name : boot
State : Ready
Hot Spare Policy violated : Not Assigned
Virtual Disk Bad Blocks : No
Secured : Not Applicable
Progress : Not Applicable
Layout : RAID-5
Size : 48.99 GB (52602470400 bytes)
Device Name : /dev/sda
Bus Protocol : SAS
Media : HDD
Read Policy : No Read Ahead
Write Policy : Force Write Back
Cache Policy : Not Applicable
Stripe Element Size : 128 KB
Disk Cache Policy : Disabled
ID : 1
Status : Ok
Name : data1
State : Ready
Hot Spare Policy violated : Not Assigned
Virtual Disk Bad Blocks : No
Secured : Not Applicable
Progress : Not Applicable
Layout : RAID-5
Size : 2,742.89 GB (2945150484480 bytes)
Device Name : /dev/sdb
Bus Protocol : SAS
Media : HDD
Read Policy : No Read Ahead
Write Policy : Force Write Back
Cache Policy : Not Applicable
Stripe Element Size : 128 KB
Disk Cache Policy : Disabled
ID : 2
Status : Ok
Name : swap
State : Ready
Hot Spare Policy violated : Not Assigned
Virtual Disk Bad Blocks : No
Secured : Not Applicable
Progress : Not Applicable
Layout : RAID-5
Size : 48.99 GB (52602470400 bytes)
Device Name : /dev/sdc
Bus Protocol : SAS
Media : HDD
Read Policy : No Read Ahead
Write Policy : Force Write Back
Cache Policy : Not Applicable
Stripe Element Size : 128 KB
Disk Cache Policy : Disabled
ID : 3
Status : Ok
Name : data2
State : Ready
Hot Spare Policy violated : Not Assigned
Virtual Disk Bad Blocks : No
Secured : Not Applicable
Progress : Not Applicable
Layout : RAID-5
Size : 2,742.89 GB (2945150484480 bytes)
Device Name : /dev/sdd
Bus Protocol : SAS
Media : HDD
Read Policy : No Read Ahead
Write Policy : Force Write Back
Cache Policy : Not Applicable
Stripe Element Size : 128 KB
Disk Cache Policy : Disabled
_______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
