topic QlikView Server slower with more CPUs in QlikView

QlikView Server slower with more CPUs

pover — Mon, 26 Jan 2026 18:19:17 GMT

Hello all,

I have a machine with 1 CPU, 4 cores, 8 system threads and 8 GB RAM which calculates the same graphs in half the time as a machine with 2 CPUs, 8 cores, 32 system threads and 64 GB RAM. Both have QV Server V9 SR5 and neither machine is virtualized.

Has anybody experienced something similar?

Thanks for the help.

Regards,

Karl

QlikView Server slower with more CPUs

Clever_Anjos — Wed, 01 Sep 2010 19:11:14 GMT

It´s really kind of weird.

Are the CPU´s the same model?

Did you compare the CPU graph while the graph is being calculated?

QlikView Server slower with more CPUs

pover — Wed, 01 Sep 2010 22:06:29 GMT

The slow machine runs on Windows 2008 R2 Enterprise with Intel(R) Xeon(R) CPU X7560 @2.27GHz 2.26GHz (2 procesadores)

The other machine runs on Windows 7 Professional with Intel(R) Core(TM) i7 CPU Q 820 @ 1.73 1.73 GHz.

My 2 ideas are that is has something to do with the configuration of Windows or something's wrong with the controllers.

Karl

QlikView Server slower with more CPUs

Thu, 02 Sep 2010 01:12:48 GMT

A few things to consider:

- Are the CPU's similar floating point throughput (clock speed is NOT the only comparison)

- Is the memory speed the same

- Is the Bus speed the same

- Is the qlikview process multithreaded - you can gauge this by percent of CPU used

- Is either opsys running 64 bit

Given you have two entirely different machines, a radical performance difference is not at all surprising

QlikView Server slower with more CPUs

csellei — Thu, 02 Sep 2010 22:36:25 GMT

Are you accessing QlikView via Access Point or Remote Desktop?

Opening the aplication is slower to?

If yes, do you have Windows FireWall active in QlikView Machine?

Windows FireWall in Windows Server 2008: I had an issue some time ago. QlikView Aplications with 200.000 records use to work very slow in a 4 cores machine when accessing via Access Point or opening with QV desktop via Remote Desktop. The solution: allowing ports 80 and 7474 within Windows Firewall.

QlikView Server slower with more CPUs

csellei — Thu, 02 Sep 2010 22:39:06 GMT

Ups !!!!! I mean port 4747

QlikView Server slower with more CPUs

pover — Fri, 03 Sep 2010 20:48:34 GMT

The slower machine has has the following characteristics

Memoria: 1066MHz DDR3 BUS: QPI de 6.4GT/s (No existe bus frontal)
Spec Floating Point rate: SPEC2006 FP_RATE 2 CPU X7560 = 283

I've attached the server architecture.

Regards.

QlikView Server slower with more CPUs

Sat, 04 Sep 2010 00:12:48 GMT

I dont think windows server 2008 sr2 is completely stable for multi-threaded application, have you tried installing windows server 2003?

Regards

QlikView Server slower with more CPUs

Sat, 04 Sep 2010 10:02:32 GMT

Hi,

Try disabling the hyperthreading in CPU . See here http://andpointsbeyond.com/category/qlikview/

"Hyperthreading is designed to help deal with unoptimized applications and the limitations of operating system schedulers. My understanding from the last time that hyperthreading was actively marketed is that QlikView does not benefit and can actually suffer when hyperthreading is enabled. QlikView has highly optimized code and uses it's own threading algorithms to maintain peak performance. Hopefully someone from QlikTech can confirm in the comments that hyperthreading is not advisable.

-Alex

QlikView Server slower with more CPUs

pover — Sun, 05 Sep 2010 05:21:53 GMT

Thanks, Alex. I'm going to look into hyperthreading.

QlikView Server slower with more CPUs

pover — Wed, 08 Sep 2010 21:41:54 GMT

Just to give some kind of close to this issue, I'l like to add that disabling the hyperthreading didn't change the performance of the QV Application on the server. IBM delivered another server that is a slighly older model and finally the performance of QV was acceptable. After confirming another similar case that also involved a IBM server, we've come to the conclusion that the newest IBM server models don't seem to work well with QlikView. We're waiting for IBM to give us a solution.

QlikView Server slower with more CPUs

Thu, 30 Sep 2010 08:50:31 GMT

Hej Karl,

Windows Server 2008 is running on both IBM machines?

Do you are using the R2 edition of w2k8?


 The basic notion behind SMT parking is that the Windows scheduler will attempt to schedule threads so that all physical cores are occupied before any core gets two threads scheduled on its two front-ends (or logical cores). Since Hyper-Threading involves some cache partitioning and other forms of resource sharing, this is a potentially important feature. We've seen scheduler quirks cause poor and oddly unpredictable performance on Core i7 processors in the past. Based on our limited experience testing with Windows 7 and a cadre of SMT-enabled processors for this review, our initial impressions of SMT parking are positive. We've seen performance results for executables that rely on the Windows scheduler for thread allocation that match the performance of executables with explicit, SMT-aware thread affinity built in. Our initial sense is that SMT parking blunts some potential disadvantages of Hyper-Threading, making it more of an unqualified win, even on the desktop.

Source: http://techreport.com/articles.x/17545/2

QlikView Server slower with more CPUs

pover — Thu, 30 Sep 2010 18:15:33 GMT

Yeah, they both have Win 2008 R2. IBM is continuing to do tests to see what is wrong.

Regards.

QlikView Server slower with more CPUs

Wed, 06 Oct 2010 17:34:00 GMT

Definitely sounds like a hardware issue. I'm glad that IBM is taking care of it. I've been working on a similarly spec'd system from Dell and performance has been wonderful. There are very few of these systems out there, so if you need a benchmark on our server I may be able to help.

QlikView Server slower with more CPUs

jorgefsilva — Fri, 08 Oct 2010 11:28:24 GMT

Hi Karl, do you had any answer from IBM to resolve this issue?

I've a scenario similar to your's... do you solve it?

Thanks,

Jorge

QlikView Server slower with more CPUs

Fri, 08 Oct 2010 11:52:29 GMT

I think QV10 takes into account the multiple cores alot better than QV9.

QlikView Server slower with more CPUs

pover — Fri, 08 Oct 2010 19:49:37 GMT

No news yet from IBM. They were able to improve the performance, but it still doesn't run as fast as my laptop. If and when I find out something, I'll post it.

We tested QV 10 and we didn't see any improvement.

Regards.

QlikView Server slower with more CPUs

pover — Wed, 20 Oct 2010 01:09:25 GMT

Ok, so we've tried 2 other large industrial strength servers from another Intel family and HP and every server a process QlikView chart even slower then a smaller, older server and my laptop. You might say that the server would run better with more users, but with 2 users (56 seconds per chart) the servers take almost twice the time as 1 user (34 seconds per chart). I guess it might run better with 100 users, but this is crazy.

I apparently have a magic laptop because the same graph takes 15 seconds per chart.

Does anybody know about any of the following:

- Has anybody had any relation with the QlikTech Scalibility Center?

- Who else is having a similiar situation?

Regards.

QlikView Server slower with more CPUs

Thu, 21 Oct 2010 13:08:03 GMT

Hi,

Are there some complicated formulas in those charts, or just a lot of data?

Disable CPU hyperthreading. Suppose there is sizeable amount of memory, so don't let Windows automatically manage the size of the pagefile. Use a fixed amount of pagefile, ex 2 GB. The old mantra swap = two times the memory does not apply for a tool called "in memory analytics"; you really need data to fit in memory.

To do a one-to-one comparison with laptop, limit QVS service from using all CPU cores from QEMC : System : Setup: QlikView Servers : Performance : CPU affinity. Choose same amount of cores as in the laptop. Use the Windows task manager to really see the rest of the CPU cores idle.

-Alex

QlikView Server slower with more CPUs

Thu, 21 Oct 2010 13:31:20 GMT

Hi Karl,

here are a suggestion from my colleagues:

Some time ago we had some performance problems in with newer machines as well. It was caused by the Win2008 default power plan "Balanced". We experienced much better (script) performance when we turned the power plan to "High Performance".
Maybe it's the case in your scenario as well..
I changed the Power Plan from "Ballenced" (which is default, so check after install OS ?) to "High Performance", since Windows 2008 SR2 does not support Intel Turbo Boost in other modes.
So it takes now 23 minutes (a little slower than on our server, but that's plaubible because of lower CPU clocking / smaller cache).

from MS Performance Tuning Guidelines for Windows Server 2008 R2, Page 14:

Processor Performance Boost Policy :
Intel Turbo Boost Technology is a feature that allows Intel processors to achieve
additional performance when it is most useful (that is, at high system loads).
However, this feature increases CPU core power consumption, so we configure Turbo
Boost based on the power policy that is in use. Turbo Boost is enabled for High
Performance power plans and disabled on Balanced and Power Saver plans for the
current generation of processors. For future processors, this default setting might
change depending on the power efficiency of such features. To use the Turbo Boost
feature under the Balanced or Power Saver plans, you must configure the Processor
Performance Boost Policy parameter.
The Processor Performance Boost Policy is a percentage value from 0 to 100. The
default value of this parameter is 35 percent on Balanced and Power Saver plans. Any
value lower than 51 disables Turbo mode. To enable Turbo Mode, set this value to 51
or higher.
The following commands set Processor Performance Boost Policy to 100 on the
current power plan. Specify the policy by using a GUID string, as shown below:
Powercfg -setacvalueindex scheme_current sub_processor 45bcc044-d885-
43e2-8605-ee0ec6e96b59 100
Powercfg -setactive scheme_current

Note that you must run the powercfg -setactive command to enable the new
settings. You do not need to reboot the server.
To set this value for power plans other than the current selected plan, you can use
aliases such as SCHEME_MAX (Power Saver), SCHEME_MIN (High Performance), and
SCHEME_BALANCED (Balanced) in place of SCHEME_CURRENT. Replace "scheme
current" in the powercfg -setactive commands shown above with the desired alias to
enable that power plan. For example, to adjust the Boost Policy in the Power Saver
plan and make Power Saver the current plan, run the following commands:
Powercfg -setacvalueindex scheme_max sub_processor 45bcc044-d885-43e2-
8605-ee0ec6e96b59 100
Powercfg -setactive scheme_max

Good luck!

Rainer