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Conference mvblab::alphaserver_4100

Title:AlphaServer 4100
Moderator:MOVMON::DAVISS
Created:Tue Apr 16 1996
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:648
Total number of notes:3158

501.0. "nfs slow performance" by DAIVC::BENNY (I am the only one) Wed Feb 19 1997 04:31

Dear all,

I have a problem with System performance while the SAP Application activated
using AS 4100 Rackmount (2 units)
The configuration of the system :

- AlphaServer 8400 as a SAP Database Server that connected to SW800.
- AlphaServer 4100 Rackmount as a SAP Application Server that mounted several
  file system from Database Server using NFS.
- Operating System D-UNIX 3.2G
- Firmware Revision 3.8 for both Machine
- 2 DE500-AA installed at 4100 and it set as 10MB.

When all machine up, there was no problem with the performance of AS4100.
But after my customer activated the SAP Application, the performance of 
system become slowed. I tried to checked it using netstat, and the information
of network collusion was very high.

This problem accoured while application activated. But it become normally when
deactivated application.

Does anybody has nearly the same problem ..?
Please reply ASAP..

rgrds
daivc::ramadoni
T.RTitleUserPersonal
Name		DateLines
501.1more info neededNAMIX::jptFIS and ChipsWed Feb 19 1997 11:0727
	I wish you had provied more details:

>- AlphaServer 4100 Rackmount as a SAP Application Server that mounted several
>  file system from Database Server using NFS.

>system become slowed. I tried to checked it using netstat, and the information
>of network collusion was very high.

	- What is your definition for high collision rate?
	- what do all other indicators tell? (like vmstat and iostat)
	  (could you list few samples from netstat/iostat/vmstat)
	- what these systems share through NFS? Just user directories or
	  database related files like Oracle home (if you're even using
	  Oracle)

	There are many other things that may need to be checked before
	true answers can be given, but as you jumped to conclusion
	that it's fault of NFS you must have done some further analyzis
	of the traffic? Have you used nfswatch? Are NFS locks enabled?

	Without further details, and problem related to application 
	startup, you might have cpu, memory, io or network io related
	problem... NFS may be a good guess, but without details, it's
	just another guess.

		-jari
501.2Another suggestion....STEVMS::BOWSEWed Feb 19 1997 13:278
    
    	Check to be sure that your LAN config is correct.  DE500 will cause
    	similar issues if you have mis-matched duplex modes.  Shut-down the
    	systems and from console so a >>> SHOW EW*_MODE.  Be sure that all
    	DE500s on any given LAN are set the same, if not ensure that your
    	UTP hub/Switch (if you have one) supports multiple modes.
    
    	- Walt
501.3resetup nfsDAIVC::RAMADONIFri Feb 21 1997 02:3939
    
To : -Jari, Walts

I really appreciated  for your quick reply. Actually there is a progress after made a simulation.
And I found out that the big possibility of the problem caused by NFS setup.
Because after resetup NFS at AS8400, the performance of Application Server is good.

The simulation that we have made :

1]. Configured AS4100 as a local SAP Application Server that connected to AS8400 using TCP/IP.
    There is no problem with the performance after activated the application.
2]. Configured SAP Application Server using NFS that connected to AS8400.
    The problem of performance still occured after activated the application.
3]. Reconfigured NFS setup at AS8400 and activated application.
    there is no problem with the performanca.

About the high collision of network, I think it caused by high traffic of data as an impact
of NFS-setup.

All filesystem that mounted from AS8400 using NFS consist of executable file of SAP and part
of Application Server profile that configured at Database  Server.

All DE500 has been setted up as 10Mbit at this time, and the UTP hub/switch supports for 
multiple mode.

I'm sorry that I couldn't give you more detail information at this time. But I will collect
all detail information.

Once again, thanks and I'm waiting your comment especially about nfs-setup.


rgrds
daiuc::ramadoni