Increasing Buffer size

[Former Member]

Hi

I am using MS-SQL Server and application server, In tune summary

the hit ratio is showing 99% , Sometime the system becomes slow and swaps will show and highlighted as red mark

My Collegues recommend to do some tunning in the SAP system, but i don't have idea where to tune and increase the buffer size. Do I really need tunning in application server

please guide me how to tune buffer size and how much to be increase

regards

Piroz

[Former Member]

Hi

I am having physical memory 16 GB RAM and operating system is MS-SQL with 400GB space install under 32bit and going through Application server.

seeing my paramter what is the best method to tune the system and what paramater to be increase

#.******************************************************************************************************************************

#.* *

#.* Instance profile WG4_DVEBMGS04_WAGNER-SAP0 *

#.* *

#.* Version = 000037 *

#.* Generated by user = Piroz *

#.* Generated on = 26.05.2007 , 12:06:30 *

#.* *

#.******************************************************************************************************************************

abap/buffersize = 950000

abap/fieldexit = yes

abap/heap_area_dia = 2000000000

abap/heap_area_nondia = 3000000000

abap/heap_area_total = 3000000000

abap/heaplimit = 40000000

abap/swap_reserve = 20971520

abap/use_paging = 0

DIR_DATA = D:\usr\sap\WG4\DVEBMGS04\data

DIR_PAGING = D:\usr\sap\WG4\DVEBMGS04\data

DIR_REORG = D:\usr\sap\WG4\DVEBMGS04\data

DIR_ROLL = D:\usr\sap\WG4\DVEBMGS04\data

DIR_SORTTMP = D:\usr\sap\WG4\DVEBMGS04\data

DIR_TEMP = .

DIR_TRANS = D:\usr\sap\trans

em/address_space_MB = 512

em/blocksize_KB = 1024

#.* EDITED BY THIJ 20070716 em/initial_size_MB = 1698 *

em/initial_size_MB = 12288

em/stat_log_size_MB = 20

em/stat_log_timeout = 0

icm/server_port_0 = PROT=HTTP,PORT=8004,EXTBIND=1

install/codepage/appl_server = 4103

INSTANCE_NAME = DVEBMGS04

login/disable_multi_gui_login = 1

login/system_client = 410

PHYS_MEMSIZE = 12288

rdisp/appc_ca_blk_no = 100

rdisp/gui_auto_logout = 0

rdisp/PG_MAXFS = 32768

rdisp/PG_SHM = 32768

rdisp/ROLL_MAXFS = 32768

rdisp/ROLL_SHM = 32768

rdisp/wp_ca_blk_no = 300

rdisp/wp_no_btc = 5

rdisp/wp_no_dia = 20

rdisp/wp_no_enq = 1

rdisp/wp_no_spo = 1

rdisp/wp_no_vb = 2

rdisp/wp_no_vb2 = 1

rsdb/cua/buffersize = 12000

rsdb/ntab/entrycount = 70000

rsdb/ntab/ftabsize = 80000

rsdb/ntab/irbdsize = 12000

rsdb/ntab/sntabsize = 3000

rsdb/obj/buffersize = 12288

rsdb/obj/max_objects = 8000

rtbb/buffer_length = 15000

SAPGLOBALHOST = wagner-sap01

SAPSYSTEM = 04

SAPSYSTEMNAME = WG4

zcsa/installed_languages = EFDR

zcsa/presentation_buffer_area = 7500128

zcsa/system_language = E

zcsa/table_buffer_area = 80000000

ztta/roll_area = 2000896

ztta/roll_extension = 2000683008

ztta/roll_first = 1024

So what parameter will anyone suggest to increase for best performance and i am around 200 swaps hits , where can i increase the page size in the parameter

[markus_doehr2]

abap/buffersize = 950000

rsdb/cua/buffersize = 12000

rsdb/ntab/ftabsize = 80000

rsdb/ntab/irbdsize = 12000

rsdb/ntab/sntabsize = 3000

rsdb/obj/buffersize = 12288

rtbb/buffer_length = 15000

zcsa/table_buffer_area = 80000000

So what parameter will anyone suggest to increase for

best performance and i am around 200 swaps hits ,

where can i increase the page size in the parameter

You are going to hit the 2 GB limit if you increase your parameters higher....

If you add all your buffers you use roughly about 1.2 GB for buffers, that means, that a user context can get a max. of 800 MB for its data, if more is requested, you will get a dump STORAGE_PARAMETER_WRONG_SET due to the limitation of a 32bit platform being able to only allocate a max. of 2 GB per process, even if there´s more memory available. I would NOT recommend increasing them more.

200 swaps are pretty ok. They can occur if you transport customizing requests to the system and so fragmenting the buffers. If you stay under 1000 a day the system should performe quite well with your settings.

--

Markus

[Former Member]

You can address 3GB of memory per process with the /3GB switch

Said above the numbers look too big and i doubt they are needed - swaps are part of a system. Its not an admins goal to get 0 swaps, its to provide a balanced system. I'd be looking at moving to 64bit and 3tier not 2 in the near future.

[Former Member]

U are running 32 bit environment

I would deffinately add /3GB and /PAE in your boot.ini so that

your work process can address more than 2GB

From,

PT.

[ken_halvorsen2]

You've mentioned "Sometime the system becomes slow and swaps will show and highlighted as red mark". What else is going on in the system? At these times are there many jobs and or reports going on? Is the performance dragging at one particular time or always during a specific processes? Can some or all of these jobs or reports be scheduled and run in the Off hours? Is it possible for 1 large report or program to be broken down in to smaller variants and run sequenctially?

It would be a shame to start tuning the settings with out checking out the entire picture and understanding what is making the performance drag.

[Former Member]

Hi All

Anyhow I increase the memory size to 4 times, before it was only 3GB I increase to more 9 GB lets see how it works

Thanks for your support

[markus_doehr2]

Check http://service.sap.com/performance

--> Media Library

--> TechEd 2005: Performance in a Nutshell

Tuning is a system dependent process and is iterative. This means, that the optimum values are adjusted over time. The sizes of the buffers depend on many things, e.g. number of modules, number of users, transports running into the system, available memory, unicode or non-unicode and more.

If you´re just started production, you will usually have an Early Watch taking place on your system. Someone from SAPs EW-Team will have a look at the system remotely and finally you will get a report of what you can do to optimize your system and what buffers to tune and how.

If you haven´t had that service yet, ask your SAP sales rep to get a contact for your. That service is included for a GoLive of a production system.

--

Markus

[Former Member]

#.* Instance profile WG4_*

#.* *

#.* Version = 000037 *

#.* Generated by user = PIROZ *

#.* Generated on = 26.05.2007 , 12:06:30 *

#.* *

#.******************************************************************************************************************************

abap/buffersize = 950000

abap/fieldexit = yes

abap/heap_area_dia = 2000000000

abap/heap_area_nondia = 3000000000

abap/heap_area_total = 3000000000

abap/heaplimit = 40000000

abap/swap_reserve = 20971520

abap/use_paging = 0

DIR_DATA = D:\usr\sap\WG4\DVEBMGS04\data

DIR_PAGING = D:\usr\sap\WG4\DVEBMGS04\data

DIR_REORG = D:\usr\sap\WG4\DVEBMGS04\data

DIR_ROLL = D:\usr\sap\WG4\DVEBMGS04\data

DIR_SORTTMP = D:\usr\sap\WG4\DVEBMGS04\data

DIR_TEMP = .

DIR_TRANS = D:\usr\sap\trans

em/address_space_MB = 512

em/blocksize_KB = 1024

em/initial_size_MB = 1698

em/stat_log_size_MB = 20

em/stat_log_timeout = 0

icm/server_port_0 = PROT=HTTP,PORT=8004,EXTBIND=1

install/codepage/appl_server = 4103

INSTANCE_NAME = DVEBMGS04

login/disable_multi_gui_login = 1

login/system_client = 410

PHYS_MEMSIZE = 12288

rdisp/appc_ca_blk_no = 100

rdisp/gui_auto_logout = 0

rdisp/PG_MAXFS = 32768

rdisp/PG_SHM = 32768

rdisp/ROLL_MAXFS = 32768

rdisp/ROLL_SHM = 32768

rdisp/wp_ca_blk_no = 300

rdisp/wp_no_btc = 5

rdisp/wp_no_dia = 20

rdisp/wp_no_enq = 1

rdisp/wp_no_spo = 1

rdisp/wp_no_vb = 2

rdisp/wp_no_vb2 = 1

rsdb/cua/buffersize = 12000

rsdb/ntab/entrycount = 70000

rsdb/ntab/ftabsize = 80000

rsdb/ntab/irbdsize = 12000

rsdb/ntab/sntabsize = 3000

rsdb/obj/buffersize = 12288

rsdb/obj/max_objects = 8000

rtbb/buffer_length = 15000

SAPGLOBALHOST = wagner-sap01

SAPSYSTEM = 04

SAPSYSTEMNAME = WG4

zcsa/installed_languages = EFDR

zcsa/presentation_buffer_area = 7500128

zcsa/system_language = E

zcsa/table_buffer_area = 80000000

ztta/roll_area = 2000896

ztta/roll_extension = 2000683008

ztta/roll_first = 1024

Do you think i need to increase or tune anything in the script please

[markus_doehr2]

Nobody will be able to tell because nobody does know your actual system. Those are your current settings and they may or may not fit.

Is this a 64bit Windows?

--

Markus

[Former Member]

Its not easy to tell from raw numbers.

You have 12GB of ram (PHYS_MEMSIZE = 12288)

Wheres the DB? how much memory and cpu does that have?

Whats the WP status in SM50? Do you have free WPs?

Try limiting the workload of the server by REDUCING the number of WPs. Each WP will reserve the memory allocation you have setout below. so each has 950000 for the program buffers - which is very high. each has.... Do you need them this high or have you just done what most do and selected the highest number you can think of?

em/blocksize_KB is low

em/initial_size_MB is low

rsdb/cua/buffersize = 12000 - do you use CUA. V high

rsdb/ntab/entrycount = 70000 V high

rsdb/ntab/ftabsize = 80000 V high

rsdb/ntab/irbdsize = 12000 V high

I think you are trying to hold too much in memory. Swap are unavoidable, you need a balanced system. However without physically seeing the system you will have to make a measured judgment. No magic answer.

You also have 4 languages which makes a difference in terms of performance