My server becomes slow when more users login. What could be the reason? Is it because of less
hardware resource?
Server configuration is 104GB HDD, 2GB Ram. OS:Win 2003 server. Database:Oracle.
I manage SAP R/3 4.6C systems on Risc 6000 machines,
under Oracle 9.2.
The overall performance problem for me is to know if
SAP response time is acceptable ; if not, do this :
- at AIX level : utilities are topas, to catch what's
wrong : Disk I/O ? CPU bottleneck ? Too much swap ?
- at Oracle level : tkprof but don't know much about this.
- at SAP level : you can manage SAP memory, Oracle and OS
too.
If SAP response time is acceptable, then try this :
Try to have a look at OS response time : ST06 : look at
CPU, Memory, Swap, Disk and Lan response time.
Try to have a look at buffer quality : ST02, if many
fields are red, investigate each fields dependant parameters.
Try to have a look at DB response time : ST04N,
databuffer quality (SGA zone), how much physical reads / logical reads Ratio,
wait times, number of user calls, Shared Pool cache hit ratio should be >96%,
Sort usage, Redo logging.
I use this kind of procedure to manage my systems.
It depends how much you allocated for SGA (database
buffers, shared pool buffer, redo log buffers), how much you allocated for SAP
buffers esp. Program buffers and whether the server have any other external
processes/programs running.
How many Dialog Work Processes you allocated�I think
your problem most likely is you don�t have enough of these Dialog processes.
Also maybe users running inefficient reports/programs which are holding the
Dialog processes, goto SM50 & check all DIA (Dialog) with status �waiting��if
ALL are �running� then you have wait time (problems !) for other users wanting
to process transactions .
To troubleshoot performance, you need these tcode
tools:-
ST04 � Database � in here, check especially for
Expensive SQLs (Detail Analysis � SQL Request)
ST02 � SAP buffers
ST06 � OS stats
ST05 � SQL trace
SE30 � Abap runtime analysis
A few step which you can exercise to sort/identify
performance issues.
* ST03, ST02, ST04 are the tcode for workload, tuning
and DB Performance Monitoring codes.
* ST06 FOR Operation System Monitoring.
** SM51 OR SM50 is process overview which tells you the
workprocess sequence. ( Ideally 10-15 process with OLTP and batch process
scheduled at peak and off peak times respectively) say 8-17 hrs and 17-8 hrs for
Batch Process)
Operation Mode can be configured in RZ04 tcode.
** Check for top CPU in ST06 tcode. CPU should not
exceed more than 60% for long time for any process.
** Based of No. of instances ( Application Servers )
should have adequately sized.
** Most resources intensive process have to be
scheduled in Batch Process ( in Background in Non Peak Hours )
** Look for unnecessary Jobs Active During Prime Time
** Look for Parameters Set To Your Business Process.
( RZ10, RZ11 ) Check Snote:0124361
** Refer Early Watch Alert Periodically for Overall
System Performance.. ( Tcode SDCC )
