Hej,
We have found that some of our root based applications seems to run
2-4 times slower with root_v3.05.04 as compared to root_v3.04.02.
In order to find the reason of decreased performance we have run standard
root benchmarks with precompiled root versions as well as root_v3.05.04
compiled from sources.
The comparison was done on the same computers with the only difference
being root version used. Most dramatic difference is with
$ROOTSYS/test/hsimple.cxx which seems to be more than 4 times slower with
ROOT 3.05/04.
Does anyone observed similar decrease of performance with root_v3.05.04
or have hints what could be wrong?
Andrzej Kupsc
---------------------------------------------------------------
The Svedberg Laboratory,
Uppsala University, Uppsala.
---------------------------------------------------------------
--------------------
Results of the tests
--------------------
ROOT versions used for tests:
root_v3.04.02.Linux.RH7.2.gcc296.tar.gz
root_v3.05.04.Linux.RH7.3.gcc296.tar.gz
root_v3.05.04 recompiled from sources was also tested but that make
no differences with root_v3.05.04.Linux.RH7.3.gcc296
also we have tried root_v3.05.03 which behaves similar
**1** Script benchmark.C is 2x slower for hsimple and
hsum we run it on our 2 computers (1 and 2 processor)
with RH 7.1 (but results are similar on a computer with RH 7.3)
computer1: 2x Pentium III
cpu MHz : 799.693
kernel : 2.4.18-27.7.xsmp
Processing benchmark: rootmarks.C
---------------ROOT 3.04/02 benchmarks summary--------------------
hsimple : Real Time = 0.71 seconds Cpu Time = 0.65 seconds
hsum : Real Time = 0.31 seconds Cpu Time = 0.30 seconds
.....
---------------ROOT 3.05/04 benchmarks summary--------------------
hsimple : Real Time = 1.32 seconds Cpu Time = 1.21 seconds
hsum : Real Time = 0.83 seconds Cpu Time = 0.83 seconds
....
computer2: 1x Intel(R) Pentium(R) 4 CPU 1.80GHz
gcc version 2.96 20000731 (Red Hat Linux 7.1 2.96-98)
Linux: 2.4.7-10
Processing benchmark: rootmarks.C
---------------ROOT 3.05/04 benchmarks summary--------------------
hsimple : Real Time = 1.62 seconds Cpu Time = 0.89 seconds
hsum : Real Time = 1.10 seconds Cpu Time = 0.60 seconds
....
Processing benchmark: rootmarks.C
---------------ROOT 3.04/02 benchmarks summary--------------------
hsimple : Real Time = 0.84 seconds Cpu Time = 0.47 seconds
hsum : Real Time = 0.42 seconds Cpu Time = 0.22 seconds
....
**2**
Standard $ROOTSYS/test/hsimple.cxx with standard Makefile was used.
In order to test speed the event loop in the hsimple.cxx were increased to
1M events and TStopwatch was put at the beginning and at the end of the
program to measure performance.
computer1:
ROOT 3.05/04
./hsimple
Time : RT= 11.53 s Cpu= 11.44 s
ROOT 3.04/02
./hsimple
Time : RT= 2.20 s Cpu= 2.19 s
computer2:
ROOT 3.05/04
./hsimple
Time : RT= 7.88 s Cpu= 7.67 s
ROOT 3.04/02
./hsimple
Time : RT= 1.87 s Cpu= 1.84 s
This archive was generated by hypermail 2b29 : Thu Jan 01 2004 - 17:50:11 MET