Performance monitoring....sd46

[bigdaddy01]

Hey guys,

I am doing some performance monitoring on a v440, the oracle tool the DBA is using has comming up with disk sd46 being a bottle neck. I am not sure how to find out what this is in Solaris? It is not in vmstat or iostat that I can find.

I assume that it is swap being thrashed? can anyone confirm this?

Any help is much appreciated.

 

[Mike042]

When you use iostat, by default it only reports on a few of the total number of disks in the system. sd46 is "scsi disk number 46". To find out which disk (c?t?d?s?) is being referenced by sd46 try:
ls -al /dev/sd46*

Don't forget that when you use iostat the first line of output gives the statistics since the last boot. To get the current values try:
iostat 1 6
which produces a table of 6 lines, the last 5 of which are at one second intervals.

To see the statistics for other disks, enter a list of up to 4 in the command line before the interval and count, eg:
iostat sd46 sd47 1 6

For further information on the iostat command, please see the man pages (man iostat)

I hope that helps.

Mike

 

[daFranze]

if you find out sd46 is realy the bottleneck, you can use the strategy Oracle calls SAME (stripe and mirror everything): create a striped volume over two or more controllers
If you like to test some scenarios change the interlace factor to 8k, which is 1/2 "Oracle Block"

Interlace Factor is easy to setup in SDS:

man metainit
....
     -i interlace
           Specifies the interlace size. This value tells  Volume
           Manager how much data to place on a slice of a striped
           or RAID level 5 metadevice before  moving  on  to  the
           next  slice.  interlace is a specified value, followed
           by either `k' for kilobytes, `m' for megabytes, or `b'
           for  blocks. The characters can be either uppercase or
           lowercase. [b]The interlace specified cannot be less than
           16 blocks, or greater than 100 megabytes. If interlace
           is not specified, it defaults to 16 kilobytes.[/b]

Best Regards, Franz
--
Solaris System Manager from Munich, Germany
I used to work for Sun Microsystems Support (EMEA) for 5 years

 

[sunixadm]

Hi,

Do iostat -E and find sd46
Now do iostat -En and you will wich device sd46 is.

-Joe