swap device io

[Tolga Evren]

Hi ,

 

This is my fstab output:

 

[oracle at tanidw1 proc]$ cat /etc/fstab

LABEL=/                 /                       ext3    defaults
1 1

/dev/md1                /boot/efi               vfat    defaults
0 0

none                    /dev/pts                devpts  gid=5,mode=620
0 0

LABEL=/home             /home                   ext3    defaults
1 2

none                    /proc                   proc    defaults
0 0

#none                   /dev/shm                tmpfs   defaults
0 0

/dev/md2                swap                    swap    defaults
0 0

/dev/cdrom              /mnt/cdrom              iso9660
noauto,owner,kudzu,ro 0 0

/dev/cdrom              /mnt/dvd                udf
noauto,owner,kudzu,ro 0 0

/dev/sdd1 /oracle/quorum ocfs _netdev 0 0

/dev/sde1 /oracle/data01 ocfs _netdev 0 0

/dev/sdf1 /oracle/data02 ocfs _netdev 0 0

 

 

according to this /dev/md2 is the swap device.

 

when i monitor the system ny using sar -B which shows paging operations
, i see  heavy page ins and outs:

 

08:35:14 AM  pgpgin/s pgpgout/s  activepg  inadtypg  inaclnpg  inatarpg

08:35:17 AM  54993.00   2242.67    178616    117518      7333     60693

08:35:20 AM  55719.33   2233.33    178616    117518      7333     60693

08:35:23 AM  39684.67   2611.00    178616    117518      7333     60693

08:35:26 AM  60330.00   3418.00    178616    117518      7333     60693

08:35:29 AM  50921.67   3545.67    178621    117518      7333     60694

 

 

 

But i see no io through the swap device:

 

iostat -x /dev/md2 1

 

avg-cpu:  %user   %nice    %sys   %idle

         119.78    0.02   34.73  869.47

 

Device:  rrqm/s wrqm/s   r/s   w/s  rsec/s  wsec/s avgrq-sz avgqu-sz
await  svctm  %util

md2        0.00   0.00  0.00  0.00    0.00    0.00     0.00     0.00
0.00   0.00   0.00

 

 

So , what can be the reason for this? 

 

Kind Regards,

tolga