SAP Hana Slow performance after update to SP11

[Former Member]

Dear All

The SAP ERP 6.0 EHP7 Development system was working fine with Hana Rev. 102 on Suse Linux 11 SP4.

To update SP06 to SP10, the sum asked to update database to >102, for which I have updated it to SP11 (Rev. 110).

After that I can see that the SAP Performance is degraded.

The Kernel is updated to the latest (742. 314).

In CCMS, I can see the high DBRequest time.

Also in Hana Studio, for some activities, or refreshing any activity take long time.

Then I installed QA system directly on Rev. 110...but I noticed the degraded performance, even though the sgen is complete

What is happening here is that when a transaction is executed first time it take long time. when the same transaction is called back again, it is executed immediately.

How can I check this.

Need advice.

Regards

Imran

[Former Member · Accepted solution]

Hello,

There is a note release in Feb. 2016 related to performance that can help:
2266533 - Bad Performance of CHECK_TABLE_CONSISTENCY on Large Tables after Upgrade to SAP Hana SPS11

The solution is:

Apply SAP HANA Revision 111 or later.

Remark:
•If you are on SAP HANA Revision 111 or later, please check if the following parameter is set to '0'. This will switch back to the old memory intensive implementation:

    indexserver.ini -> [table_consistency_check] -> keypositions_maxsize = 0

[Former Member · Accepted solution]

Dear Andres

Yes I saw the sapnote....I have to check that...but seems to be valid for this issue.

[terrence_yang]

we have upgraded to rev.111 and the performance is normal now..

we also tried double the max_concurrency and sql_executors (after that we didn't observer high concurrency of statistics server run) on rev.110 and the system performance was normal...not sure if this is another issue...

[Former Member]

Hi Imran,

Can you please check if the systems have been utilized enough to have the column store tables loaded into memory

Your description of the issue seems to be related to tables that are yet to be loaded into memory resulting in slow first transaction followed by good performance

You could execute the *HANA_Memory_Overview* script under the SAP note 1969700 to understand the largest tables using the memory

Check for any symptoms of errors under the indexserver trace log file that indicates any issue

Do not think we have heard of any specific issues with SPS11 released earlier last week from any customers yet and there are no specific SAP Notes that point us to any specific settings that need to be enabled to overcome any known issues on SPS11

On our side we are also on SPS10 and looking forward to upgrading our non prod systems to SPS11 at some point next year so it is quite useful to understand the behavior of SPS11

Hope it helps

Sunil

[Former Member]

Dear Sunil

Thanks for support. I have executed the scripts....the result file is attached.

Need advice.

Regards

Imran

HEQMemoryscript.zip

[Former Member]

I have attached the script result for Dev also now....

Just to share that we are running dev and qas on VMware. with 128GB Ram, with 8 Cores.

One thing I have noticed that in dev_w* file this entry is very command and repeated again.

M PfStatWrite: OS CPU-time Problem (10000 > 2198)

The CPU time is different for each entry....I am not sure if this is helpful....

My SAP System is on SP10 with kernel 724- 315

Regards

Imran

HEDMemoryScript.zip

[Former Member]

Hi Imran,

Firstly the memory usage report looks alright except for the GLOBAL ALLOCATION LIMIT(110 GB) and the LICENSE USAGE(88 GB)

Looks like you have more memory allocated for your system than the Licensed memory

They should be set to the same number normally, however I do not think that is going to affect your performance

The report also confirms the Columnstore and Rowstore tables along with Heap memory usage is much below the license usage so there does not seem to be any memory pressure here

The slowness is most likely due to the Columnstore tables that are loaded into memory during the first transaction by the Application

You could open a case with SAP support if you think the issue persists and any old transactions start getting slower

Hope it helps

Sunil

[terrence_yang]

Hi Sunil,

we are experiencing exact the same situation at one customer here.

We have installed CRM on HANA sps11  on sles 11 sp4 on vmware (256GB memory with 10 vCores).

and when we run tcodes for first time it takes long (even several minutes to run just SE80 or SP02, etc), then run second time is very fast.

there's another sandbox system which is running on HANA SPS9, and is running much faster.

Please suggest how we can tune on HANA side?

[Former Member]

Dear All

I have revert back my systems to Hana SP10....now working much better...

I am not sure what is specially required for SP11..but my gcc lib and kernel levels are higher than the required for sp11...but still it didn't work.

I have checked the Performance guide, but as this is the new installation, I don't think there is need to check expensive sql statements...as these are owned by sap....Further the parameter settings are at Default proposed by sap.

Regards

[terrence_yang]

Hi Imran,

How did you roll back to SP10? since we use fresh installation of SP11, it seems not possible to roll back to SP10...please suggest. Thanks!

Regards,

Terrence

[Former Member]

Dear Terrence

Actually I had the system with new installations...so I just uninstalled it , and installed it again with Hana SP10.

Regards