Sudden increase of Swaps in Export/import buffer

[Former Member]

Hi All,

Sudden Increase of SWAPS in Export/Import buffer in BI system. Please help me in resolving the issue.

Buffer

HitRatio %      Alloc.

KB Freesp.

KB % Free      Sp. Dir.       Size FreeDirEnt

% Free Dir

Swaps

DB Accs

Export/import

98,96

100.000

7.431

8,02

20.000

16.289

81,45

284.044

Efficiency	HITRATIO	%	99
	HITS	2.938.848
	REQUESTS	2.969.662
	DB access quality %	100
	DB access	0
	DB access saved	0
	Reorgs	0
Size	Allocated	KB   100.000
	Available	KB	92.653
	Used	KB	84.315
	Free	KB	7.431
Directory entries Available	20.000
	Used	3.711
	Free	16.289
Swaps	Objects swapped	6.118
	Frames swapped	284.044
Resets	Total	0

History :

Date	Hit rate DB quality Al.adr.sp. St.avail. Free Stor. DB acc. Max. obj. Free Objs Swapped o. Time

bp1vci_BP1_10 Export/Import buffer (EIBUF)

Wed 07.08.2013 98,9594   100,0000	100.000	92.653	7.393	0	20.000	16.276	284.044  06:40:16
Tue 06.08.2013 98,9579   100,0000	100.000	92.653	6.012	0	20.000	15.428	243.525  23:00:21
Mon 05.08.2013 99,0011   100,0000	100.000	92.653	4.720	0	20.000	14.905	94.297  23:00:21
Sun 04.08.2013 99,0717   100,0000	100.000	92.653	34.450	0	20.000	16.497	94.297  23:00:17

Current Parameter Values :

Buffer Name	Comment
Profile Parameter	Value  Unit  Comment

Export/import buffer EIBUF

rsdb/obj/buffersize	100000 kB	Size of export/import buffer
rsdb/obj/max_objects	20000	Max. number of objects in the buffer

rsdb/obj/large_object_size 8192   Bytes Estimation for the size of the largest object

rsdb/obj/mutex_n

0

Number of mutexes in Export/Import buffer

Thanks and Regards

Vijay K

[Reagan]

Hello

Buffer	HitRatio %    Alloc.
Export/import	98,96       100.000

What matters is the Hit Ratio.

A hit ratio of 99% is absolutely fine. There is no need to tune these parameters.

Regards

RB

[Former Member]

Hi Vijay,

From the hit usage the buffer looks ok  and a high number of swaps is only a problem if the buffer has no time to do anything other than load and displace objects. You can recognize this situation from the buffer hit ratio. You can use transaction ST02 to determine the hit ratio. The hit ratio should be higher than 80 %.

For mode info please read this below note.

Note 373986 - Overflow of the export/import buffer

Can you please go in the export and the import buffer in st02 and go in buffer objects.

Can you see an invalid entries in there.

Can you also check the below note if you at lower kernel to what mentioned in this note.

Note 1740934 - Buffer synchronization: Avoiding duplicate entries

Hope it helps .

Thanks

Rishi Abrol

[Former Member]

Hi All,

@ Benjamin  : Yes, the Hit Ration is 99% but Swaps have increased suddenly from 0 (on 01.08.2013) to 94.297 (on 02.08.2013) to 243.525 (on 06.08.2013) and now 284.044 (07.08.2013), So I am concerned with that as this is a Production system. Will this cause any Performance Issue ?? in near future.

@ Rishi :

In the Note 373986 , we have 2 solutions

Sol .1 -->  My system satisfies solution1 and Last Restart was on 12.07.2013.

Sol .2 --> Free Space is almost 10%.

and I cannot find any invalid objects in St02.

we have to go with option( Note : 1740934 patch Upgrade 311)

Kernel release

720

Sup.Pkg lvl.

300

Unicode System

Yes

[Reagan]

Hello

So I am concerned with that as this is a Production system. Will this cause any Performance Issue ??

The note 373986 clearly says when you should use Solution 2

The hit ratio should be higher than 80 %. If it is lower than this, proceed as described in solution 2.

export/import buffer is not a critical buffer so that can barely influence the performance metrics.

If a work process gets the data from the buffer then it is a hit and if not it is a miss.

Note 649613 - Export/import buffer SWAPS

Regards

RB

[Former Member]

Hi Benjamin,

Thanks for the Reply ..

The Solution 2 of the Note 373986 states to maintain around 10% of the Free space, but we have more than 10% of the free space, So I think it is not applicable to us.

Size	Allocated	KB   100.000
	Available	KB	92.653
	Used	KB	78.137
	Free	KB	12.758
Directory entries Available	Available	20.000
	Used	7.894
	Free	12.106

The Note 649613, is for lower releases and mine is SAPBASIS Release 7.01 and level is 06.

Thanks and Regards

Vijay K