transferrate between XP 256 and Server

[Werner Placke]

hy admin's,
i want to know the transferrate between a server hp9000 n4000 an the xp 256. There is an adabas-database installed (character device) on volumegroups on the server. seemingly there is a performanceproblem. therefor i need some info's :
what kind of scsi-contoller is in system and how can i get some info's about the transferrate between server and xp 256

sorry for my english!
Thank's for your help!

Werner Placke

[Paul R. Dittrich]

Internally, the XP256 has a control bus running at 130 MBps and data bus at 240 MBps.
(that's "B"ytes, not "b"its) I believe all the available disks are dual-ported high-speed drives from Hitachi. And you have a minimum of 1 GB of cache to a maximum of 16 GB cache.

Externally, between server and array, my opinion is that if you don't use Fiber Channel then you wasted the money for the XP256.

Have you tried any of the performance monitoring tools like top or sar or glance? They should give valuable clues to where the performance bottleneck really is.

HTH,
Paul

[Werner Placke]

that's the question i have: which command i must use to get the nessecary info's. the command :
glance is not at the system
top shows process-info's
sar seemt the right command, but there are many options and i'm not sure to use it!

[Stefan Farrelly · Accepted solution]

The command you want to use to test the data transfer rate (speed) to the XP256 is dd.

Find a device in /dev/rdsk which is on the XP256 (ioscan -fknCdisk will list all the device names) and do the following to test its throughput;

time dd if=/dev/rdsk/cxxxxxx of=/dev/null bs=1024k count=100

This will transfer 100 MB. Then divide 100 by the time output from above and this will give you a transfer rate. If you are using fibre I would expect around 100+MB/s (we get almost the max 170 MB/s on our fibre connections to an FC60/SC10).

[Marcelo De Florio_1]

YOU could execute one operation from or to disk (xp-256)
and then execute
sar -d 1 5
the output for this command is:
device %busy avque r+w/s blks/s avwait avserv
c1t6d0 3.00 0.50 2 20 3.63 16.64
look avserv and r+w/s total operation by second
MDF